529 KEW BULLETIN 62: 529–560 (2007) A taxonomic revision of the genus Phymatidium (Orchidaceae: Oncidiinae) A. L. V. Toscano de Brito1 Summary. A taxonomic revision of the genus Phymatidium Lindl. is presented. Ten species and two varieties are recognised. One species, P. glaziovii Toscano, and one variety, P. delicatum var. curvisepalum Toscano, are newly described. A key to species and varieties is presented. Each species and variety is described and illustrated, and history and synonymy discussed. Key words. Orchidaceae, Phymatidium, taxonomy, morphology. Introduction The genus Phymatidium belongs to the Ornithocephalus group of subtribe Oncidiinae (Orchidaceae), and was established by Lindley in 1833 based on P. delicatum and P. falcifolium. Lindley’s description was extremely short and lacked any illustration. He described Phymatidium as lacking stems and pseudobulbs (“Herbae...acaules, ebulbes”) and described the column as possessing a swollen base (“Columna...basi tumida”). Lindley was correct in stating that pseudobulbs are absent, but he was wrong to state that Phymatidium species are stemless; they do possess stems, although these may occasionally be extremely short or inconspicuous. The swollen column-base is present in all but one Phymatidium species, although it is not always swollen. A tabula infrastigmatica, as this basal part of the column has been recently interpreted (Toscano de Brito 2001), also occurs in most members of subtribe Oncidiinae (Chase 1999) and also in some other genera of the Ornithocephalus group, such as Platyrhiza Barb. Rodr., Hintonella Ames, and Thysanoglossa Porto & Brade. However, its general shape in Phymatidium is very distinctive. Phymatidium species were first illustrated by the Brazilian botanist João Barbosa Rodrigues (1842 – 1909), Director of Rio de Janeiro Botanical Garden, in his Iconographie des Orchidées du Brésil, which has only been published recently and posthumously by Sprunger et al. (1996). Barbosa Rodrigues illustrated four species of which three were considered by him to be new to science. As his herbarium appears to have been destroyed (Sprunger et al. 1996), his illustrations are the only original material available today. Barbosa Rodrigues was also the first to contribute significantly to the taxonomy of Phymatidium. In his work Genera et Species Orchidacearum Novarum(1882), he described the new taxa illustrated in his Iconographie and recognised four species in the genus, namely: P. delicatum Lindl., P. myrtophilum Barb. Rodr., P. hysteranthum Barb. Rodr. and P. tillandsioides Barb. Rodr. For unknown reasons he omitted Lindley’s P. falcifolium from his account. Barbosa Rodrigues enlarged Lindley’s generic concept, adding information on the column morphology, especially the anther and pollinarium, both missing from Lindley’s original description. The pollinarium was also reported for the first time to have four pollinia. Bentham (1883) provided an expanded generic description of Phymatidium, as well as further information on the morphology of the column, anther and pollinarium. This extra information suggests that he had more material for study than Lindley. However, he recognised only two species, P. delicatum and P. falcifolium, probably because he had not seen Barbosa Rodrigues’ work before he finished the orchid account for Genera Plantarum (Bentham 1883). Cogniaux (1905) revised the genus Phymatidium in his treatment of the Orchidaceae for Martius’ Flora Brasiliensis. The five species he recognised were separated into two groups according to the presence or absence of a distinct stem, the leaf arrangement, shape and consistency, and the number of veins in the leaves. With the exception of leaf shape and consistency, the other characters used by him have proven unreliable for the taxonomy of Phymatidium. Cogniaux also provided illustrations of all the species Accepted for publication November 2006. 1 Address for correspondence: Rua 15 de Novembro, 60, Centro, Rio de Contas, Bahia, Brazil CEP: 46170-000. New affiliation: Associated Researcher at Departamento de Ciências Biológicas, Universidade Estadual de Feira de Santana, Bahia, Brazil. © The Board of Trustees of the Royal Botanic Gardens, Kew, 2007 530 except P. falcifolium. These illustrations were made from engravings based on Barbosa Rodrigues’ original drawings. Cogniaux’s generic description was largely based on that of Bentham (1883) while his species concepts were essentially those of Barbosa Rodrigues (1882). Unfortunately, as will be demonstrated here, he seems to have experienced difficulties in correctly identifying most Phymatidium species. For instance, his description of P. delicatum was based on a mixed collection of at least four different taxa; specimens cited under P. hysteranthum include an undescribed taxon, and he failed to recognise P. tillandsioides as a synonym of P. falcifolium even after having studied a considerable number of specimens including the holotype of P. falcifolium. He was not alone in experiencing such difficulties. Lindley confused P. hysteranthum with P. delicatum in his own herbarium, while Barbosa Rodrigues (1882) considered his Ornithocephalus microphyllus (= Phymatidium microphyllum (Barb. Rodr.) Toscano), which is a good species, to be a synonym of P. delicatum, and described P. myrtophilum as new based on a specimen which is here considered to represent the true P. delicatum. Among the references cited by Cogniaux (1905) the following did not contribute substantially to the taxonomy of Phymatidium: Endlicher (1836), Meisner (1842), Bentham (1881), Kerchove de Denterghem (1894), Müller (1895), Pfitzer (1889). Müller (1895), however, provided important data on germination and seed morphology of this genus. After Cogniaux’s revision some sporadic contributions on Phymatidium appeared in the literature including descriptions of new species. These include Schlechter (1920, 1925), Porto & Brade (1937), Williams & Hoehne (1947), Hoehne (1949), Pabst & Dungs (1977), Senghas (1995), and Bock (1998a,b). Pabst & Dungs (1977) provided a checklist with synonyms and data on distribution of all ten species known to them. Phymatidium geiselii, a species described by Ruschi in 1976, was not included in their account. More recently, Toscano de Brito (2001) has provided a systematic review of all 12 genera of the Ornithocephalus group of subtribe Oncidiinae in which the history, seed morphology, phytochemestry, anatomy, morphology, pollination, taxonomy and nomenclature of this genus are reviewed. The vegetative and floral morphology of Phymatidium are discussed in detail and this is not repeated here. Toscano de Brito (1998, 1999) gives details of leaf anatomy and seed morphology, Williams et al. (1994) a profile of the flavonoids. Phymatidium consists of ten species restricted mainly to south-eastern Brazil; one species has been recorded from Uruguay and another from Argentina. They grow as epiphytes on trees and © The Board of Trustees of the Royal Botanic Gardens, Kew, 2007 KEW BULLETIN VOL. 62(4) shrubs in the forests and are frequent in disturbed and cultivated areas. It is readily distinguished from all other genera of the Ornithocephalus group by its spiral phyllotaxy and the cupulate or flange-shaped caudicles of the pollinarium. Taxonomy Phymatidium Lindl. (1833: 209); Barb. Rodr. (1882: 227); Cogn. (1905: 232); Pabst & Dungs (1977: 20); Senghas (1995: 1901); Toscano (2001: 209). Lectotype: Phymatidium delicatum Lindl. (designated by Toscano de Brito 2001). Delicate, monopodial epiphytic herbs, usually forming dense and intricate clumps. Roots few to many, terete, flexuous, glabrous or papillose, usually thick, somewhat flexuous, occasionally quite long and forming a cluster of several adnate roots or an intricate clump of several roots, usually scattered along the stem and arising from the base of the leaf-sheath. Stem very short, inconspicuous, or rarely elongated, terete, ascending, usually proliferous, often irregularly branched, each branch usually producing roots and flowers. Pseudobulbs absent. Leaves few to many in a dense and irregular spiral along the stem, unifacial, rarely bifacial, non-articulated, erect or spreading, rarely arching, coriaceous or rarely soft and slightly fleshy, usually somewhat falcate and ensiform to linearsubulate, usually somewhat twisted and asymmetric, often varying in cross-section in the same specimen and the same leaf, semi-terete, subterete, oval, semioval to 3-angled in cross-section, rarely dorsiventrally flattened, slightly sheathing and shortly decurrent at base, acute or acuminate, pale-green. Inflorescences 1 to many, few- to many-flowered, racemose, laxly flowered, axillary, occasionally producing flowering plantlets; peduncle usually angular to somewhat elliptic in crosssection, usually finely papillose on the angles, somewhat flexuous to slightly zig-zag, often somewhat twisted, covered by few to several widely spaced, usually subulate sterile bracts; rachis usually angular, flexuous to zig-zag; floral bracts similar to the sterile ones. Flowers few to many, small, usually resupinate, with spreading segments or not opening widely, usually white with a green centre. Pedicel somewhat twisted and angular, often bent near the apex. Ovary pedicellate, slightly angular to slightly 3-keeled. Sepals free, subsimilar, variable in shape, membranaceous, acute to obtuse, carinate abaxially, with entire margins; the dorsal sepal usually slightly concave; lateral sepals usually falcate and oblique, spreading, porrect, reflexed or curved upwards. Petals free, variable in shape, usually slightly oblique, spreading, erect, arching upwards, inflexed or recurved, acute to obtuse; the margins entire, rarely waved or sinuate, A TAXONOMIC REVISION OF THE GENUS PHYMATIDIUM often slightly convex, abaxially slightly carinate. Lip free, usually deflexed and convex, variable in shape when spread, sessile or broadly unguiculate with a cordiform, rarely rhombic blade, acute to distinctly acuminate, base provided adaxially with a fleshy, concave, usually somewhat ligulate callus which is glandular within; margins usually denticulate or erose near the middle, rarely entire. Column short, somewhat clavate, usually sigmoid, incurved or geniculate, wingless or auriculate and usually recurved near the often strongly sigmoid apex; the auricles rarely reduced to small flaps on each side of the column near the level of the rostellum; stigmatic cavity usually small, ovate to elliptic, located at base of the column, rarely large and occupying almost a third of the column; rostellum entire or 3-lobed, very short or conspicuous, curved or projecting forward, rarely recurved and somewhat hooked; base of the column extended into an usually thick, swollen, and variously shaped tabula infrastigmatica (absent in one species), 531 which is often flanked at the base, near the stigmatic cavity, by two fleshy auricles or arm-like appendages; clinandrium ventral or dorsal; anther terminal, ventral or somewhat dorsal, operculate or hooded, ovate, narrowly ovate, slightly clavate to somewhat panduriform in outline, usually distinctly beaked, acute to obtuse, usually very shortly recurved and emarginate at apex; pollinia 4, arranged in two superposed unequal or slightly unequal pairs, usually globose, pyriform, obovoid or clavate, each pair attached to stipe apex by cupulate or lanceolate flange-shaped caudicles; viscidium ventral, small, concave, ovate to elliptic. Fruits pedicellate, capsular, subglobose, weakly ridged, somewhat carinate to markedly winged, often with persistent perianth. ETYMOLOGY. The generic name derives from the Greek phyma, a tumour or swelling, plus the Greek diminutive suffix idium, probably in reference to the often thick and swollen tabula infrastigmatica. Key to Species and Varieties of Phymatidium 1. Leaves unifacial, variable in transverse section: semi-terete, oval, somewhat 3-angled to terete but never V-shaped · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · 2 Leaves bifacial, dorsiventrally flattened, V-shaped in transverse section · · · · · · · · · · · · · · · 10. P. falcifolium 2. Column extended at base into a variously shaped, thick tabula infrastigmatica · · · · · · · · · · · · · · · · · · · · · 3 Column without a tabula infrastigmatica · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · 6. P. aquinoi 3. Column distinctly auriculate at apex · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · 4 Column never auriculate, the apex often prolonged into a 3-lobed rostellum, the base provided with two erect arms or fleshy auricles which flank the tabula infrastigmatica · · · · · · · · · · · · · · · · · · · · · 5 4. Auricles of the column distinctly papillose · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · 6 Auricles of the column glabrous or rarely obscurely papillose · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · 7 5. Lip somewhat panduriform with an usually erect and cuneate lamella projected beyond the main callus · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · 8. P. mellobarretoi Lip ovate or lanceolate without a lamella projected beyond the main callus · · · · · · · · · · · · · · · · · · · · · · · 8 6. Lip usually broadly unguiculate, rarely subsessile; blade usually cordiform to rhombic, margins erose to denticulate in the middle. Capsules obscurely ridged, often slightly 3-angled in crosssection · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · 9 Lip sessile, broadly lanceolate, margins entire or slightly sinuate towards the apex. Capsules markedly 3-winged with alternating, usually less pronounced ridges, in cross-section · · · · · · · 2. P. geiselii 7. Lateral sepals strongly reflexed; anther distinctly beaked with two small lateral teeth at apex · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · 4. P. hysteranthum Lateral sepals spreading or curved forwards; anther ovate-panduriform, usually with a hint of a tooth on each side near the apex · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · 11 8. Lip. c. 5 – 6.5 mm long, rhombic; lateral lobes of rostellum tooth-like, much shorter than the middle one · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · 7. P. limae Lip c. 3.5 mm long, ovate-lanceolate; rostellum entire · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · 9. P. vogelii 9. Lip subsessile, distinctly rhombic and markedly acuminate; tabula infrastigmatica conspicuously nose-shaped in side view · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · 3. P. glaziovii Lip unguiculate, rarely subsessile; blade usually cordiform, rarely ovate-rhombic or broadly ovate-lanceolate; tabula infrastigmatica variable in shape and size but never conspicuously nose-shaped in side view · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · 10 © The Board of Trustees of the Royal Botanic Gardens, Kew, 2007 532 KEW BULLETIN VOL. 62(4) 10. Lateral sepals spreading and curved upwards; column with dilated and dorsiventrally flattened tabula infrastigmatica which is broadly ovoid to somewhat subglobose from above · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · 1b. P. delicatum var. curvisepalum Lateral sepals not curved upwards; tabula infrastigmatica very variable in shape but never broadly ovoid to somewhat globose, neither dilated nor dorsiventrally flattened · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · 1a. P. delicatum var. delicatum 11. Flowers opening widely with spreading segments · · · · · · · · · · · · · · 5a. P. microphyllum var. microphyllum Flowers not opening widely; petals and sepals curved forwards · · · · · · · · · 5b. P. microphyllum var. herteri The species of Phymatidium are here allocated to four alliances: P. delicatum, P. aquinoi, P. mellobarretoi, and P. falcifolium. Key to the Alliances of Phymatidium 1. Leaves unifacial, variable in transverse section: semi-terete, oval, somewhat 3-angled to terete but never V-shaped · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · 2 Leaves bifacial, dorsiventrally flattened, V-shaped in transverse section · · · · · · · · · IV. P. falcifolium Alliance 2. Column extended at base into a variously shaped, thick tabula infrastigmatica · · · · · · · · · · · · · · · · · · · · · 3 Column without a tabula infrastigmatica · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · II. P. aquinoi Alliance 3. Column distinctly auriculate at apex; rostellum usually quite small and curved or projecting forwards; the base without arms or auricles flanking the tabula infrastigmatica · · · I. P. delicatum Alliance Column never auriculate, the apex often prolonged into a 3-lobed rostellum, the base provided with two erect arms or fleshy auricles which flank the tabula infrastigmatica III. P. mellobarretoi Alliance I. Phymatidium delicatum Alliance Column auriculate at the apex, with a thick, swollen tabula infrastigmatica. Anther operculate, usually beaked, somewhat incurved, and very shortly recurved and emarginate at apex, with a pair of small teeth, often very reduced, near the apex. Pollinia are attached to the stipe through a pair of lanceolate, flange-like caudicles. Rostellum usually quite small and curved or projecting forwards. Stigmatic cavity is small, ovate to elliptic, placed at the base of the column. Lip usually somewhat unguiculate with an erose or denticulate blade, and a basal, concave, thick, ligulate callus, hairy-glandular within. In one species the lip is clearly sessile with entire margins. Leaves coriaceous, unifacial, semi-terete to terete. Five species: P. delicatum, P. glaziovii, P. geiselii, P. hysteranthum, and P. microphyllum. 1. Phymatidium delicatum Lindl.(1833: 210); Barb. Rodr. (1882: 228); Warm. (1884: 847); Cogn. (1905: 233, excl. synon. illustr. et spec. cit. in part.; 1907: 336); Kraenzl. (1911: 78); Hoehne (1949, t. 286. f. 1); Pabst & Dungs (1977: 202, excl. illustr.); Senghas (1995: 1902, excl. illustr.); Johnson, (2001: 160 – 161, 241); Toscano (2001: 176, f. 10, A – B; 210, f. 29). Type: Brazil. Santa Catarina: Isle of Santa Catarina, Fischer (Langsdorff s.n.) (holotype K!; ?isotype K!). © The Board of Trustees of the Royal Botanic Gardens, Kew, 2007 Phymatidium myrtophilum Barb. Rodr.(1882: 229); Cogn.(1905: 225, t. 48, f. 2); Schltr. & Hoehne (1921: 46; 1926: 294); Pabst (1953: 89 ); Pabst & Dungs (1977: 202, f. 2202). Type: Brazil. Rio de Janeiro: Barbosa Rodrigues s.n. (Lost). Lectotype, here designated: Barbosa Rodrigues’ original illustration which appeared in his Iconographie des orchidées du Brésil, vol. 6, plate 315, fig. B (Library of Rio de Janeiro Botanical Garden!), reproduced in Sprunger et al. (1996: 443). ?Phymatidium paranaense A. Samp. (1916: 59, t. 2). Type: Brazil: Paraná: Dusén s.n. (holotype R, spirit, not located). Plant very small, up to c. 20 mm tall, usually forming dense and intricate clumps. Roots many, terete, flexuous, thick, glabrous. Stem up to c. 15 mm long, erect, branched. Leaves several, c. 15 × 1.5 mm, ensiform, falcate, subulate, usually somewhat twisted and asymmetric, very variable in cross-section, semiterete, subterete to somewhat 3-angled, slightly sheathing and shortly decurrent at base, pale green. Inflorescences few to several, up to c. 100 mm long, fewto many-flowered, racemose; peduncle up to c. 50 mm long, slightly angular in cross-section, finely papillose on the angles, covered by several widely spaced, decurrent, thickish, subulate sterile bracts, c. 4 × 1 mm; rachis up to c. 30 mm long, zigzag; floral A TAXONOMIC REVISION OF THE GENUS PHYMATIDIUM bracts similar to the sterile ones, decreasing in size towards the apex of inflorescence. Flower usually resupinate, white with green centre and spreading segments. Pedicel 2 – 4 mm long, twisted, slightly angular, shortly papillose on the angles, bent near the apex. Ovary 0.5 – 2 mm long, angular, papillose on the angles. Dorsal sepal 2.5 – 3.5 × 0.3 – 1 mm, usually concave towards base and somewhat hooded, narrowly ovate, ovate-triangular or oblong-lanceolate, usually slightly concave, acute to obtuse, abaxially weakly to distinctly carinate. Lateral sepals 2 – 4 × 0.3 – 0.8 mm, spreading, narrowly ovate to oblonglanceolate, slightly to distinctly falcate, sometimes curved upwards becoming subparallel to the petals, weakly concave, acute to obtuse-mucronate, abaxially carinate. Petals 2 – 3.5 × 0.5 – 1 mm, spreading, ovatelanceolate, oblong-lanceolate or narrowly ovate, usually slightly oblique and falcate, usually concave towards apex, acute to obtuse, sometimes shortly mucronate, usually abaxially distinctly carinate. Lip 2 – 4 × 1.5 – 3.5 mm, broadly unguiculate, rarely subsessile; blade cordiform, rarely ovate-rhombic or broadly ovate-lanceolate, usually rather convex and deflexed; margins erose at the middle of the lip, becoming entire towards the base and the apex; base provided with a glandular, concave, ligulate to subquadrate callus which occupies most of the claw of the lip (c. 1/3); apex acute, acuminate. Column 1 – 3 mm long (excluding the tabula infrastigmatica), arching, slightly to distinctly sigmoid, sulcate underneath, slightly to markedly recurved towards apex, auriculate, the auricles somewhat broadly ovate when spread, densely papillose; stigmatic cavity small, ovate, placed at base of the column; rostellum very short, slightly curved forward; tabula infrastigmatica variable in shape and size, usually 0.5 – 1 × 0.5 – 1 mm, rarely inconspicuous, thick, solid, laterally excavated when seen from the side, usually obovatetrapeziform, broadly ovoid to subglobose in outline from above, with a raised obovoid to ligulate (rarely sagittate) longitudinal callus in the middle, the apex of the column usually somewhat emarginate with two lateral, divergent, small teeth; anther 1 – 1.5 mm long, operculate, narrowly ovate to obscurely panduriform in outline, apex very shortly emarginate and recurved; pollinia arranged in two superposed slightly unequal pairs, pyriform; stipe c. 1.2 mm long, narrowly obovate-cuneiform, curved forwards at base, apex emarginate, truncate or emarginate-apiculate; viscidium very small, subelliptic. Capsule 2 – 3 × 1.5 – 3 mm, subglobose, the pedicel 2 – 4 mm long. Fig. 1. The specific epithet comes from the Latin delicatus, delicate, and refers to the small delicate plants and flowers. NOTES. Since its publication by Lindley in 1833, Phymatidium delicatum has been consistently ETYMOLOGY. 533 misidentified (e.g. Barbosa Rodrigues 1882; Cogniaux 1905; Pabst & Dungs 1977; Senghas 1995). Most published illustrations have been wrongly named and most specimen citations are usually a mixture of different taxa. As a consequence, the taxonomy of this common species is highly confused. The problem can be traced to 1882 when Barbosa Rodrigues considered Ornithocephalus microphyllus Barb. Rodr. (= Phymatidium microphyllum (Barb. Rodr.) Toscano), a valid species, as conspecific with Phymatidium delicatum in his Genera et Species Orchidacearum Novarum. In the same work, he described a new species, Phymatidium myrtophilum, which was based on a specimen of the true P. delicatum. Cogniaux (1905), apparently following Barbosa Rodrigues, provided illustrations of P. myrtophilum and P. delicatum in his account for Martius’ Flora Brasiliensis. The engraved illustrations presented in this account (t. 48, f. 2 and t. 56, f. 1) were based upon Barbosa Rodrigues’ original drawings of Phymatidium myrtophilum (a synonym of P. delicatum) and Ornithocephalus microphyllus, respectively. Most subsequent authors appear to have based their identification of P. delicatum on the incorrectly named illustration in Flora Brasiliensis, thereby perpetuating Barbosa Rodrigues’ error. The difficulties encountered by Barbosa Rodrigues and Cogniaux in correctly identifying P. delicatum and its relatives were understandable. Lindley’s original publication of P. delicatum comprised only an extremely short description, without an illustration. Herbarium specimens of Phymatidium are difficult to study, and good rehydration of flowers using boiling water is usually difficult to achieve satisfactorily. Their flowers are very small and the differences are somewhat difficult to describe. As most species are sympatric and usually have the same flowering season, mixed collections with up to three different species on the same herbarium sheet have been found. For instance, in Lindley’s herbarium at Kew, specimens of P. delicatum are mounted together with P. hysteranthum on the same sheet. Likewise, Cogniaux (1905:234) cited, under P. delicatum, specimens of at least four different taxa, namely: P. delicatum, P. microphyllum, P. hysteranthum and P. glaziovii. A few authors, notably Hoehne (1949, t. 286, f. 1) and Johnson (2001), correctly named and illustrated P. delicatum, but this seems to have been due to misinterpretation of Cogniaux’s concepts in Flora Brasiliensis rather than to the correct interpretation of Lindley’s original concept. In Lindley’s herbarium at Kew, the type specimen of P. delicatum is mounted together with two other collections on the same herbarium sheet. The specimen which I consider to represent the holotype is labelled as “Ins. S. Catharinae, Brasilia, L.” and is situated on the upper left side of the © The Board of Trustees of the Royal Botanic Gardens, Kew, 2007 534 KEW BULLETIN VOL. 62(4) J A E F1 B1 C G K B2 F2 H D L M N2 N1 U N3 P1 P2 Q1 Q2 S1 S4 T S3 S2 © The Board of Trustees of the Royal Botanic Gardens, Kew, 2007 R A TAXONOMIC REVISION OF THE GENUS PHYMATIDIUM sheet. The “L.” most probably refers to the collector, the German explorer and naturalist Georg Heinrich Langsdorff. A second specimen, placed in a envelope on the upper right side of the herbarium sheet, agrees with the holotype and was collected by Langsdorff during his short stay in the Isle of Santa Catarina between December 1803 and January 1804, when he visited Brazil for the first time as naturalist in the Kruzernstern & Liciansky Circumnavigation Expedition (Langsdorff 1813). Langsdorff returned to Brazil as Consul-General of Russia in Rio de Janeiro in 1813 and undertook an expedition to the interior of Brazil from 1821 until 1829, but did not visit Santa Catarina again. Although Lindley cited a Fischer specimen in the type description of P. delicatum, the type specimen was most probably collected by Langsdorff during his visit to Santa Catarina. Friedrich E. L. von Fischer was the Director of St. Petersburg Botanical Gardens between 1823 and 1850, and, as far as I can ascertain, never visited Brazil. He was almost certainly responsible for distribution of Langsdorff’s duplicates to specialists in other herbaria, which would explain the citation of his name by Lindley. With the exception of Langsdorff, only a few of the early explorers and naturalists visited Santa Catarina (Urban 1906) prior to the publication of Lindley’s Genera and Species of Orchidaceous Plants (1830 – 1840), and none worked in collaboration with St. Petersburg. I believe that the specimen in the envelope is most probably a duplicate of the holotype and may have been sent to Lindley after the publication of P. delicatum. A collection with clear reference to Fischer (“Dr. Fischer”) exists in Hooker’s herbarium at Kew and may be another isotype. Cogniaux (1905: 234) cited “Fischer, Langsdorff n. 15” among the specimens of P. delicatum he examined from Santa Catarina. I have been unable to locate this specimen but it suggests that more specimens of P. delicatum collected by Langsdorff in the Isle of Santa Catarina may yet be found. The other two collections on the type sheet of P. delicatum, Miers s.n. and Gardner 644, the latter formed by two specimens, were received by Lindley after publication of his Genera and Species and have proved to be P. hysteranthum. 535 I have been unable to locate the holotype of Sampaio’s P. paranaense. Nevertheless, I have examined one specimen (Dusén 3521, R!) named by Sampaio as P. paranaense and this agreed well with P. delicatum. The drawing which appears in Sampaio’s publication agrees in every detail with P. delicatum, except for the apparent lack of papillae on the column wings. Pabst (1957), after studying material from São Francisco de Paula in the State of Rio Grande do Sul, the type locality of P. herteri Schltr. considered the latter conspecific with P. paranaense. Like the majority of authors, he also confused P. delicatum with other related species; I have examined several specimens of P. delicatum named by him as either P. herteri, P. delicatum or P. myrtophilum. Furthermore, P. delicatum and P. herteri (treated here as a variety of P. microphyllum) are sympatric, and both have been collected in São Francisco de Paula. While the identity of P. paranaense remains somewhat unclear it is most probably a synonym of P. delicatum, but certainly not the same as P. herteri. Although variable in its floral morphology, P. delicatum can be easily recognised by the shape of the column, especially the short and narrow papillose auricles. Extreme variants exist, some apparently genetically fixed; some of these might deserve taxonomic recognition. Only two of these are recognised here: P. delicatum var. delicatum and P. delicatum var. curvisepalum Toscano. 1a. var. delicatum Inflorescence up to c. 70 mm long. Dorsal sepal 2.5 – 3.5 × 0.3 – 1 mm, usually concave towards base and somewhat hooded, narrowly ovate, ovate-triangular or oblong-lanceolate, acute to obtuse, abaxially weakly carinate. Lateral sepals 2 – 4 × 0.3 – 0.8 mm, narrowly ovate to oblong-lanceolate, spreading, usually slightly falcate and weakly concave, acute to obtusemucronate, abaxially weakly carinate. Petals 2 – 3.5 × 0.5 – 1 mm, ovate-lanceolate, oblong-lanceolate or narrowly ovate, usually slightly oblique and obscurely falcate, acute to obtuse. Lip 2 – 4 × 1.5 – 3.5 mm. Column 1 – 3 mm long (excluding the tabula infrastigmatica), slightly sigmoid, slightly recurved Fig. 1. A – S Phymatidium delicatum var. delicatum. A flower; B1 dorsal sepal; B2 lateral sepal; C petal; D lip; E flower; F1 dorsal sepal; F2 lateral sepal; G petal; H lip; J – K variation in column morphology with anther and pollinarium removed; L – M variation in lip morphology; N1 anther from behind; N2 anther in front view; N3 anther in side view with pollinarium attached to the anther cap; P – Q variation in pollinarium morphology: P1 and Q1 = front view, P2 and Q2 = from behind; R habit; S.1 leaf; S2 – S4 variation in leaf transverse sections . A – D drawn from OIC 8779 (SEL); E – J, N1 – N3, R and S4 from Ferreira s.n. (K — spirit); S1 – S3 from Toscano de Brito 688 (K — spirit); K & L, from Ferreira 1716 (AMES); M from Hoehne 1874 (RB); P1 – P2 from Smith 1889 (AMES) and Q1– Q2 from Weir 482 (K). T – U. Phymatidium delicatum var. curvisepalum. (Kummrow 1582, SP). T flower; U column in side view with anther and pollinarium removed × 15. Single-line scale = 1 mm. Double-line scale = 1 cm. ALL DRAWN BY SUSANNA STUART-SMITH. © The Board of Trustees of the Royal Botanic Gardens, Kew, 2007 536 towards apex; tabula infrastigmatica variable in shape and size, usually 0.5 – 1 × 0.5 – 1 mm, rarely inconspicuous, thick, solid, usually obovatetrapeziform in outline from above, with a raised obovoid to ligulate (rarely sagittate) longitudinal callus in the middle. Fig. 1A – S. Rio Grande do Sul: Farroupilha, São Roque, Feb. 1988, Rossato et al. s.n. (HUCS!, US!); Montenegro, Pareci Novo, 18 Dec. 1955, Toillier s.n. under Rohr 2289 (HB!); Pareci, near Montenegro, 10 Dec. 1945, Henz s.n. (PACA!); São Francisco de Paula, 14 Jan. 1937, Rambo s.n., mixed collection with P. aquinoi (PACA!, B!); São Francisco de Paula, Fazenda Englert, 14 Jan. 1937, Rambo & Dutra 1811 (SP!); São Leopoldo, 1907, Theissen 665 (PACA!). Santa Catarina: without precise locality, June 1868, Müller 81 (K!); Blumenau, Feb. 1888, Ule 874 (BR!); Brusque, Azambuja, Reitz C2164 (US!); Brusque, D. Francisca, 1875, Schwacke 1348 (RB!); Isle of Santa Catarina, Fischer (Langsdorff s.n.) (holotype K!, ?isotype K); same area, Langsdorff s.n. (S!); same area, Langsdorff s.n. (K!); same area, Prescott s.n. (K!); Isle of Santa Catarina, Sertão da Lagoa, 7 Jan. 1951, Rohr 2063 (HB!); Ibirama, 17 Nov. 1953, Gevieski 9 (HB!); same area, 2 Nov. 1953, Reitz & Klein 1162 (HB!); same area, March 1954, Reitz & Klein 1560 (HB!; US!; S!; NY!); Ilhota, Morro do Baú, 30 Jan. 1964, Pereira 8778 & Pabst 8053 (HB!); Imaruí, Águas Mornas, 20 Feb. 1973, Klein & Bresolin 10865 (HB!); Imaruí, Águas Mornas, Serraria Alcides P. Alves, 16 Jan. 1973, Klein & Bresolin 10719 (HB!); Itajaí, Cunhas, 8 Feb. 1955, Klein 1156 (HB!); Joinville, 31 Dec. 1949, Hans 319 (R!); same area, 6 Jan. 1950, Hans 332 (R!; RB!); same area, Jan. 1961, Hans s.n. (R!); Joinville, Palácio Episcopal, 1 March 1958, Reitz & Klein 6525 (HB!); São Francisco do Sul, Garuvá, Três Barras, 19 Nov. 1957, Reitz & Klein 5729 (HB!); São Francisco do Sul, 31 Jan. 1964, Pereira 8803 & Pabst 8078 (HB!); São Francisco do Sul, São Francisco, Feb. 1884, Ule 236 (BR!); São João do Sul, 18 Jan. 1976, Hagelund 893 (MBM!; C!). Paraná: without precise locality, Lange 7894 (HB! — mixed collection with P. microphyllum) & Dusén 13878 (S! — mixed collection with P. microphyllum var. herteri); Antonina, 27 Feb. 1966, Hatschbach 13911 (MBM!; HB!); same area, 20 Feb. 1965, Saito 1249 & Kuniyoshi 26 (HB!); Antonina, Cacatu-Serra Negra, 18 Feb. 1967, Hatschbach 16011 (MBM!); near Alexandra, 9 Nov. 1969, Leinig 420 (HB!); Balsa Nova, Serra Santa Ana, 1 Nov. 1969, Hatschbach 23385 (MBM!); Capão Grande, 25 Jan. 1910, Dusén 9245 (S!); Campo Largo, 29 Sept. 1939, Kuhlmann s.n. (SP!); Guarapuava, Águas, Santa Clara – Rio Jordão, 16 Nov. 1963, Pereira 7935 (HB!); Guaraqueçaba, Rio do Cedro, Hatschbach 18516 (MBM!, NY!, HB!); Guaraqueçaba, Rio do Costa, 9 Feb. 1972, Hatschbach 29134 (MBM!); Guaratuba, 31 BRAZIL. © The Board of Trustees of the Royal Botanic Gardens, Kew, 2007 KEW BULLETIN VOL. 62(4) Jan. 1912, Dusén 13600 (S!); Guaratuba, Rio da Divisa, 14 Dec. 1963, Hatschbach 10865 (MBM!); Guaratuba, Rio da Praia, 31 Dec. 1966, Hatschbach et al. 15578 (MBM!); Jacareí, 12 Feb. 1912, Dusén 13870 (S!, NY!, HB!, AMES!); same area, 21 Feb. 1914, Dusén 14452 (S!); same area, 11 Feb. 1915, Dusén 16734 (S! — mixed collection with P. delicatum var. curvisepalum, K!, F!, NY!, AMES!, MO!); Jaguariaiva, Rio Samambaia, 18 Nov. 1970, Hatschbach 25465 & Guimarães s.n. (MBM!); Ipiranga, 9 Feb. 1904, Dusén 3521 (R!) & 15 Jan. 1914, Dusén 14456 (S!) & 23 Feb. 1911, Dusén 11386 (S!); Morretes, 12 Feb. 1910, Dusén s.n. (S! — mixed collection with P. microphyllum var. herteri); Passa Sete, 12 Feb. 1971, Dombreowski 3257 & Kuniyoshi 2635 (HB!); Paranaguá, Morro Ai Jesus, 24 Nov. 1967, Hatschbach 17963 (MBM!); Pién, Campina dos Crispim, 5 Dec. 1962, Hatschbach 9543 (MBM!, HB!); Piraquara, Rio do Corvo, Picada Mãe Catira, 1 May 1949, Hatschbach 1388 (MBM!); Quatro Barras, Rio Capivari, 26 Nov. 1962, Hatschbach 9486 (MBM!); Terezina, 21 Jan. 1911, Dusén 11164 (S!). São Paulo: Alto da Serra, Biological Station, 14 Feb. 1929, Smith 1889 (S!, AMES!, a duplicate of this collection at GH! belongs to P. delicatum var. curvisepalum); Butantan, 29 Oct. 1920, Hoehne s.n.(SP!, NY!, SEL! — mixed collection with P. hysteranthum); Campos do Jordão, March 1946, Leite 4078 (SP!); near Campo Grande, Serra do Mar, 1 Feb. 1914, Brade s.n. (HB!); Cotia, 28 Dec. 1926, Kuhlmann s.n. (SP!); Cubatão, Serra do Mogi, 13 Dec. 1988, Kirizawa & Lopes 2126 (SP!); Iguápe, Morro das Pedras, 2 Feb. 1919, Brade s.n. (HB!, AMES!); same area, 1923, Brade s.n. (HB!); same area, April 1924, Brade s.n. (HB!); Jaraguá, 5 May 1907, Usteri s.n. (SP!); Nossa Senhora do O, Brade s.n. (HB!); São Paulo, Dec. 1892, Loefgren, Comiss. Geogr. Geol. São Paulo 1955 (AMES!, BR!, SP! — mixed collection with P. hysteranthum); same area, 22 Feb. 1827, Burchell 4309 (K!); São Paulo, Morumbi, March 1827, Burchell 4451 (K!); São Paulo, Vila Cerqueira Cézar, 26 Nov. 1922, Hoehne s.n. (SP!); São Paulo, 16 Nov. 1939, Pickel s.n. (SP!); São Paulo, Rio Pariquerassú, Dec. 1910 – Jan. 1911, Brade 5063 (HB!, S!); São Paulo – Rio de Janeiro, 1861 – 1862, Weir 497 (K!); same area, Weir 482 (K!). Rio de Janeiro: Itatiaia, vicinity of Macieiras, 7 Jan. 1929, Ferreira 1716 (US!, S!, AMES!, G!, F!); Itatiaia, Mont Serrat, 14 July 1902, Dusén 777 (R!); same area, 1903, Dusén s.n. (S!); same area, 25 Dec. 1915, Ames 108 (AMES!); Teresópolis, Dec. 1966, Pereira s.n. (HB!). Espírito Santo: Domingos Martins, Biriri, fl. cult. 29 Dec. 1990 by Shunck s.n., Toscano de Brito 688 (RB!); Alfredo Chaves, São Miguel, 5 Feb. 1969, Kautsky 185 (HB!). Bahia: Santa Terezinha, Serra da Jibóia, Morro da Pioneira, 24 Nov. 2000, Azevedo 131 & Toscano de Brito s.n. (HRB!). DISTRIBUTION. Argentina: Recorded for the Province of Misiones by Johnson (2001). Brazil: Rio Grande do A TAXONOMIC REVISION OF THE GENUS PHYMATIDIUM Sul, Santa Catarina, Paraná, São Paulo, Rio de Janeiro, Espírito Santo, and Bahia. HABITAT. Epiphytic, usually on small branches of shrubs and trees near river margins in the forest. Also frequent in disturbed areas and orchard; recorded several times as an epiphyte on Psidium guajava L. (Myrtaceae) and other cultivated trees. Alt. 0 – 900 m. NOTES. The shape of sepals, petals, lip and tabula infrastigmatica in this taxon is very variable, but most specimens examined fall within the range of forms represented by Fig. 1A – S. The variant illustrated in Fig. 1K – L, was collected in Itatiaia, Rio de Janeiro State (Ames 108, AMES!; Ferreira 1716, US!, S!, AMES!, G!, F!) and in Campos do Jordão, São Paulo State (Leite 4078, SP!). It has an sagittate tabula infrastigmatica and lanceolate-rhombic lip. Fig. 1M, shows the weakly unguiculate lip of a variant collected in Espírito Santo (Kautsky 185, HB!), Santa Catarina (Hoehne 1874, RB!) and Paraná (Hatschbach 23385, MBM!). Besides the somewhat different and smaller lip, it also has a very short tabula infrastigmatica which sometimes resembles a small version of that in Fig. 1K. 1b. Phymatidium delicatum var. curvisepalum Toscano var. nov. a varietate typica columna distincte sigmoidea, sepalis lateralibus sursum curvatis differt. Typus: Brazil, Paraná, Quatro Barras, 4 Nov. 1980, Hatschbach 43272 (holotypus MBM!). Inflorescence to 100 mm long. Dorsal sepal 2.5 – 3 × 0.5 – 0.8 mm, narrowly oblong-lanceolate, abaxially distinctly carinate, slightly concave, acute. Lateral sepals 2.5 – 3 × 0.5 mm, curved upwards becoming subparallel to the petals, distinctly falcate, slightly concave towards apex, acute, carinate abaxially. Petals 2.5 – 3 × 0.5 – 1 mm, narrowly lanceolate-ovate to narrowly oblong-lanceolate, usually slightly falcate, weakly concave towards apex, acute to obtuse, usually shortly mucronate, abaxially distinctly carinate. Lip 3 – 4 × 2.5 – 3 mm. Column 1.5 – 2 mm long (excluding the tabula infrastigmatica), distinctly sigmoid, slightly narrowing towards the apex which is clearly recurved; tabula infrastigmatica c. 0.5 × 0.5 mm, dilated, thick, somewhat dorsiventrally flattened, broadly ovoid to subglobose when seen from above, with a obscurely raised, narrowly obovate, longitudinal callus in the middle. Fig. 1T – U. DISTRIBUTION. Brazil. Santa Catarina, Paraná, and São Paulo. Santa Catarina: Horto Florestal, 12 Nov. 1959, Smith & Klein 7556 (AMES!); São José, Serra da Boa Vista, 10 Nov. 1960, Reitz & Klein 10413 (HB!); Palhoça, 23 Sept. 1953, Bonifácio 2239 (HB!). Paraná: without precise locality, 12 Dec. 1909, Lange s.n. (S! — BRAZIL. 537 mixed collection with P. microphyllum); Boa Esperança, Rio das Mortes, 8 Nov. 1928, Hoehne s.n. (SP!); Guaratuba, near rio da praia, Leinig 267 (HB!); Palmeira, Fazenda Santa Rita, 13 Oct. 1982, Hatschbach 45646 (MBM!); Piraquara, Campininha, 27 Oct. 1946, Hatschbach 509 (MBM!, RB!, PACA!); Quatro Barras, 4 Nov. 1980, Hatschbach 43272 (holotype MBM!); Quatro Barras, Col. Japonesa, 31Oct. 1981, Kummrow 1582 (SP!, MBM!); São José dos Pinhais, Barro Branco, 11 Nov. 1965, Hatschbach 13133 (F!); Tijucas do Sul, Vossoroca, 15 Oct. 1961, Hatschbah 8448 (MBM!). São Paulo: Alto da Serra, Biological Station, 5 Feb. 1929, Smith et al. 1824 (GH!); same area, 14 Feb. 1929, Smith 1889 (GH!-a duplicate of this collection at AMES belongs to the typical variety); Biriti Mirim, Boracéia Biological Station, 4 Jan. 1984, Custódio Filho 2168 (SP!); Cunha, Parque Estadual da Serra do Mar, Núcleo Cunha, 13 Dec. 1996, Bertoncini et al. 759 (ESA!) & Bertocini et al. 750 (ESA!); same area, 16 Dec. 1996, Bertocini et al. 784 (ESA!); São Paulo, Sítio Morro Verde, 9 Sept. 1998, Izumisawa et al. 102 (PMSP!); São Paulo, Parque Estadual da Serra do Mar, Núcleo Curucutu, matinha ao redor do primeiro lago da trilha do Mirante, 29 Oct. 1998, Garcia 1645 & Alonso s.n. (PMSP!); Serra da Cantareira, IX/1912, Toledo Jr. s.n. (RB!); Serra do Mar, Rio Grande, Brade 7554 (HB!). HABITAT. Similar to that of the typical variety. Alt. 30 – 100 m. ETYMOLOGY. The epithet derives from the Latin curvisepalus referring to the lateral sepals which are always curved upwards. NOTES. This new variety differs from the typical one mainly in the general shape of the column and tabula infrastigmatica, as well as in the position of sepals and petals on the flower, which always point upwards. The sepals are curved near the base and more or less straight towards the apex. The inflorescence in some specimens is quite long, but in others it equals that usually found in Phymatidium delicatum var. delicatum. The floral morphology of P. delicatum var. curvisepalum is uniform in all specimens examined. Although it occurs in areas where the typical variety is also found, I have been unable to detect any intermediates between the two entities. Studies of reproductive biology of these varieties might provide a better understanding of their systematics and mechanisms of reproductive isolation. 2. Phymatidium geiselii Ruschi (1976: 1). Type: Brazil, Espírito Santo, Parque Nacional do Caparaó, Rio São Domingos, Várzea dos Congonhas (Macieira), 16 Aug. 1975, Albuquerque et al. s.n. (holotype MBML — spirit 6220, not located). Plant up to c. 35 mm tall. Roots several, flexuous, terete, thickish, glabrous. Stem up to c. 10 mm long, © The Board of Trustees of the Royal Botanic Gardens, Kew, 2007 538 KEW BULLETIN VOL. 62(4) erect, not branched. Leaves many, up to c. 25 × 1 mm, slightly falcate, somewhat ensiform, shortly and slightly sheathing at base, twisted, 3-angled almost to the middle, laterally flattened towards the apex, acute. Inflorescences several, up to c. 35 mm long, few- to c. 8flowered, racemose; peduncle up to c. 18 mm long, 3angled in cross-section, glabrous, thickish, covered by several narrowly ovate to subulate, acute sterile bracts, up to c. 5 × 0.8 mm, abaxially slightly keeled; rachis up to c. 16 mm long, 3-angled in cross-section, flexuous, somewhat twisted, thickish; floral bracts similar to the sterile ones, decreasing slightly in size towards the apex of the inflorescence. Flowers not resupinate, white with green tabula infrastigmatica and callus of the lip (fide original description). Ovary pedicellate, c. 6 mm long (fide original description). Dorsal sepal c. 4 x 1 mm, lanceolate to oblong-lanceolate, somewhat falcate, slightly concave, acute, abaxially weakly carinate. Lateral sepals similar in size and shape to the dorsal one; margins slightly sinuate. Petals c. 4 × 1.2 mm, obliquely ovate-lanceolate, slightly falcate, acute; margins slightly sinuate. Lip c. 4 × 2 mm, broadly lanceolate, acute; margins entire or slightly sinuate towards the apex; base with a glandular, concave, broadly ligulate callus. Column c. 2.5 mm long (excluding the tabula infrastigmatica), incurved, slightly sigmoid, sulcate underneath, slightly thicker towards the base, usually obscurely recurved near the apex, auriculate; the auricles densely papillose, obtuse, somewhat broadly ovate when spread, running from approximately the same level as the rostellum up to the apex of the column; stigmatic cavity small, ovate, placed at the base of the column; rostellum small, slightly curved forwards; tabula infrastigmatica c. 1 × 0.5 mm, thick, somewhat obovate from above, laterally sulcate, with a slightly raised, flattened, elongate, elliptic callus slightly curved upwards towards the apex; anther c. 1.5 mm long, operculate, somewhat panduriform in outline, clearly narrowly beaked, incurved towards the apex, very shortly recurved and emarginate at apex; pollinarium not seen. Capsule immature, c. 3 × 2 mm, subglobose to slightly pyriform, markedly 3-winged with alternating, usually less pronounced ridges, the pedicel c. 2.5 mm long. Fig. 2. Domingos, Várzea dos Congonhas (Macieira), 16 Aug. 1975, Albuquerque et al. s.n. (holotype MBML — spirit 6220). HABITAT. Epiphytic on trees near river margins in Atlantic cloud forest at higher altitudes. Alt. c. 1850 m. ETYMOLOGY. Named after the former President of Brazil, General Ernesto Geisel. NOTES. I have been unable to locate the type of Phymatidium geiselii, a spirit collection at Museu Mello Leitão in Espírito Santo, Brazil. However, three unidentified spirit collections were found in this museum two years after the death of its director, A. Ruschi. These contained no information but were numbered as 26, 27 and 29. They were later correctly determined by the museum’s staff as P. geiselii. All three specimens, which most probably have the same provenance as the type, have only immature fruits with flower remnants at apex, a feature also shown in Ruschi’s drawing in the original publication of P. geiselii. With the exception of the tabula infrastigmatica, which seemed somewhat shrunk in the specimens examined, the floral segments were still found in a relatively good state and have been used as basis for the floral analyses and description provided in the present work. This species is related to Phymatidium delicatum but can be readily distinguished by the shape of inflorescence, the distinctive floral morphology, especially shape of the lip, column, anther and tabula infrastigmatica, as well as by the markedly winged fruits. It is also related to P. glaziovii from which it differs in the shape of the tabula infrastigmatica, lip and fruits. It did not appear in Pabst & Dungs’ Orchidaceae Brasilienses (1977) probably because by the time P. geiselii was published in 1976, the manuscript of Orchidaceae Brasilienses vol. 2 (1977) had already been sent to press. Brazil: Espírito Santo. Without locality and collector, numbers 26, 27, and 29 (MBML! — spirit: 6125, 6126 & 6127). Espírito Santo: Parque Nacional do Caparaó, Rio São Plant up to c. 70 mm tall, usually forming a dense intricate clump. Roots many, terete, thickish, glabrous, flexuous. Stem up to c. 10 mm long, branched. Leaves up to c. 40 × 1 mm, falcate, somewhat twisted, variable DISTRIBUTION. BRAZIL. 3. Phymatidium glaziovii Toscano sp. nov. P. geiselii Ruschi affinis sed labello rhombiformi, tabula infra stigma conspicua et nasuta, fructibus aliis defectis distinguitur. Typus: Brazil, Rio de Janeiro, Glaziou 3633 (holotypus BR!, isotypus C!). Fig. 2. Phymatidium geiselii. A dorsal sepal; B – C lateral sepals; D – E petals; F – G lip; H column in side view with anther and pollinarium removed and with auricle bent backwards to show rostellumn and clinandrium; J apex of the column showing auricle in normal position; K anther in front view; L anther from behind; M anther in side view; N fruit in side view; P fruit in transverse section; Q habit. Drawn from MBML — spirit 6127. Single-line scale = 1 mm. Double-line scale = 1 cm. DRAWN BY SUSANNA STUART-SMITH. © The Board of Trustees of the Royal Botanic Gardens, Kew, 2007 A TAXONOMIC REVISION OF THE GENUS PHYMATIDIUM 539 A D N E B P C F G J H K Q L M © The Board of Trustees of the Royal Botanic Gardens, Kew, 2007 540 KEW BULLETIN VOL. 62(4) in cross-section in the same specimen and the same leaf, 3-angled, semi-terete, oval to semi-oval, slightly sheathing and shortly decurrent at base, apex acute. Inflorescences several, up to c. 110 mm long, up to c. 10flowered, racemose; peduncle up to c. 45 mm, slightly angular in cross-section, covered by several, narrowly ovate, somewhat subulate sterile bracts, up to c. 6 × 0.7 mm, acute; rachis up to c. 55 mm long, slightly flexuous, angular in cross-section; floral bracts similar to the sterile ones, decreasing in size towards the apex of the inflorescence. Flowers not resupinate, not opening widely, with the petals and sepals curved forwards and with a spreading lip. Pedicel 2.5 – 3 mm long, slightly twisted and obscurely angled. Ovary c. 1 mm long, slightly angled. Dorsal sepal c. 3.5 × 0.7 mm, linear-lanceolate to narrowly ovate-lanceolate, usually somewhat falcate, slightly concave and hooded towards the base, acute, abaxially slightly carinate. Lateral sepals c. 4 × 1 mm, linear-lanceolate to narrowly ovate-lanceolate, falcate, acute, abaxially slightly carinate. Petal c. 3.7 × 1 mm, oblong-lanceolate to somewhat ovate-lanceolate, acute, abaxially slightly carinate. Lip 4.7 – 5 × 2.7 – 3 mm, rhombic, convex, usually deflexed, somewhat unguiculate at base; margins entire and slightly involute towards the base, entire to weakly erose at middle, entire towards the apex; base provided with a glandular, deeply concave, somewhat broadly ovate callus; apex markedly acuminate. Column 2 – 2.5 mm long (excluding the tabula infrastigmatica), incurved, sigmoid, slightly thicker towards the base and somewhat recurved at apex, auriculate; the auricles densely papillose, slightly semi-elliptic to semi-ovate when spread, running from the same level as the rostellum up to the apex of the column; stigmatic cavity small, ovate, placed at base of the column; rostellum short, curved forward; tabula infrastigmatica c. 1.5 × 0.5 mm, conspicuous, laterally excavated, nose-shaped in side view, elongate, narrowly obovate and flanked at base by a shorter thick lump on each side when seen from above, adaxially flattened, slightly sulcate at middle, shortly sagittate at base; anther c. 1.5 mm long, operculate, narrowly ovate in outline, incurved towards the apex, slightly beaked, the apex shortly recurved and emarginate; pollinia arranged in two superposed unequal pairs, the superior pair narrowly clavate, the inferior oblong-ellipsoidal to narrowly obovoid; stipe c. 1.5 mm long, somewhat obovatecuneiform, the base slighlty curved, the apex subtruncate; viscidium small, ovate, concave. Capsule c. 2.5 × 1.5 mm, subglobose, slightly 3-angled in crosssection, the pedicel c. 1 mm long. Fig. 3. DISTRIBUTION. Brazil: Rio de Janeiro and Espírito Santo Rio de Janeiro: Rio de Janeiro: Glaziou 3633 (holotype BR!, isotype C!); Nova Friburgo, 26 March BRAZIL. © The Board of Trustees of the Royal Botanic Gardens, Kew, 2007 1967, Dungs s.n. (HB!). Espírito Santo: Domingos Martins, fl. cult. July 1969, Kautsky s.n. (HB!); same locality, without date, Dungs s.n. (HB!). HABITAT. Epiphytic on trees in the Atlantic forest of Rio de Janeiro and Espírito Santo. Alt. 500 – 1500 m. ETYMOLOGY. Named after Auguste François Marie Glaziou (1828 – 1906), French botanical traveller who first collected this species. NOTES. This species has been consistently confused with other species of Phymatidium. For example, Cogniaux identified Glaziou 3633 as P. hysterathum in the herbarium, but cited it under P. delicatum and P. hysteranthum in his account in Martius’ Flora Brasiliensis. Pabst has identified Dungs s.n. as P. mellobarretoi, and Kautsky s.n. as P. myrtophilum. Although quite variable in vegetative morphology, especially the length and the shape of the leaves, it is very uniform in floral morphology, particularly in column and lip shape. It is similar to P. geiselii but differs in the shape of the tabula infrastigmatica, lip and fruit. In P. glaziovii the tabula infrastimatica is slightly curved downwards towards the apex and distinctively nose-shaped in side view, the lip is rhombic with markedly acuminate apex, and the fruits are unwinged, while in P. geiselii the tabula infrastigmatica is elongate and slightly curved upwards towards the apex; the lip is broadly lanceolate, acute, and the fruit markedly 3-winged. 4. Phymatidium hysteranthum Barb. Rodr.(1882:288); Cogn. (1905: 234, t. 50, f. 1) & (1907:336); Pabst (1954:196); Pabst & Dungs (1977: 202, f. 2199); Senghas (1995: 1903, f. 1861); Miller & Warren (1996: 243, t. 40); I. Bock (1998a). Type: Brazil, Rio de Janeiro, Barbosa Rodrigues s.n. (Lost). Lectotype, here designated: Barbosa Rodrigues’ original illustration which appeared in his Iconographie des orchidées du Brésil, vol. 6, plate 315, fig. A (Library of Rio de Janeiro Botanical Garden!), reproduced in Sprunger et al. (1996: 443).. Phymatidium delicatum auct. non Lindl. (1833): Senghas (1995: 1901, f. 1860). Plant up to c. 35 mm tall, usually forming a intricate clump. Roots several, terete, thick, papillose, somewhat flexuous, usually quite long and forming a cluster of several adnate roots. Stem up to c. 15 mm long, usually inconspicuous and branched near the base. Leaves up to c. 30 × 1.5 mm, falcate, somewhat twisted, variable in cross-section in the same specimen and the same leaf, 3-angled, semi-terete, oval to semi-oval, slightly sheathing and shortly decurrent at base, the apex acute. Inflorescences several, up to c. 100 mm long, racemose, few- to c. 20flowered; peduncle up to c. 45 mm long, 3-angled in cross-section, flexuous, covered by several, fleshy, A TAXONOMIC REVISION OF THE GENUS PHYMATIDIUM 541 A B C D E G F H J K L Fig. 3. Phymatidium glaziovii. A flower in side view; B flower in side view, petal and proximal lateral sepal removed to show column and lip callus; C dorsal sepal; D petal; E lateral sepal; F lip; G column in side view; H anther in front view; J anther from behind; K pollinarium from behind; L pollinarium in front view. B – J drawn from Dungs s.n. (HB 41360); A , K – L from Glaziou 3633 (BR). Line scales = 1 mm. ALL DRAWN BY SUSANNA STUART-SMITH. © The Board of Trustees of the Royal Botanic Gardens, Kew, 2007 542 usually somewhat 3-angled in cross-section, falcate, narrowly ovate-lanceolate to linear-subulate sterile bracts, up to c. 10 × 0.5 mm, acute; rachis up to c. 55 mm long, usually slightly zig-zag, 3-angled in crosssection; floral bracts similar to the sterile ones, decreasing in size towards the apex of inflorescence. Flowers usually resupinate, white with green centre. Pedicel 3 – 5.5 mm long, somewhat twisted, slightly angular, inconspicuously papillose on the angles. Ovary 0.5 – 1 mm long, slightly three-keeled. Dorsal sepal 2.5 – 3.5 × 0.5 – 1.5 mm, oblong-lanceolate, ovate or narrowly ovate, usually somewhat lanceolate and falcate, reflexed, somewhat arching, slightly concave, acute to slightly obtuse, abaxially weakly carinate. Lateral sepals 3 – 4 × 0.5 – 1.5 mm, narrowly ovate to somewhat oblong, slightly falcate, strongly reflexed, acute to obtuse, abaxially slightly carinate. Petal 3 – 4 × 0.6 – 1.2 mm, ovate to narrowly ovate, oblong or lanceolate, usually somewhat oblique with slightly waved margins, convex, slightly reflexed and arching upwards, acute to obtuse, abaxially slightly carinate. Lip 3 – 4 × 2 – 4 mm, broadly unguiculate; blade cordiform, acute, deflexed, usually rather convex; margins dentate to erose at middle of the lip, becoming entire towards the base and the apex; base provided with a large, thick, concave, broadly ligulate callus which is glandular within and equals or slightly exceeds the length of the claw of the lip. Column 2 – 3.5 mm long (excluding the tabula infrastigmatica), clearly sigmoid, sulcate underneath; apex of the column somewhat recurved, usually somewhat apiculate, auriculate, the auricles glabrous, somewhat obliquely broadly ovate to slightly semi-lunate when spread, running from approximately the same level as the rostellum and diminishing in breadth towards the apex of the column, the margins of the auricles usually somewhat erose to crenulate; stigmatic cavity small, ovate, placed at the base of the column; rostellum very short, curved forwards; tabula infrastigmatica 0.7 – 1 × 0.6 mm, laterally excavated in side view, with a small, raised, thick, somewhat cordiform-sagittate to broadly lanceolate callus sitting on a shorter, thick, usually semi-globose to ovoid platform; anther 1.5 mm long, narrowly ovate, operculate, distinctly beaked, incurved, with a small tooth on each margin near apex, which is shortly recurved and emarginate; pollinia arranged in two superposed unequal pairs, the superior pair clavate, the inferior somewhat obovoid; stipe c. 1.2 mm long, narrowly spathulate, curved forward at the base, the apex weakly emarginate; viscidium small, somewhat rounded and concave. Capsule c. 3 × 2.5 mm, subglobose, obscurely ridged, the pedicel 2.5 – 4.5 mm long. Fig. 4. Brazil: São Paulo, Rio de Janeiro, Minas Gerais and Espírito Santo. DISTRIBUTION. © The Board of Trustees of the Royal Botanic Gardens, Kew, 2007 KEW BULLETIN VOL. 62(4) São Paulo: Alto da Serra, 10 June 1936, Herter 97951 (G!, NY!, MO!); same area, Aug. 1898, Edwall, Comiss. Geogr. Geol. São Paulo 4038 (BR!); Caraguatatuba, Parque Estadual, Serra do Mar, Pirani & Yano 793 (SP!); Juquitiba, 1 June 1980, Barros 258 (SP!); Mogi das Cruzes, Serra do Mar, 28 July 1983, Kirizawa et al. 1031 (SP!) & Kirizawa et al. 1026 (SP!); São Luiz de Paraitinga, 18 Aug. 1987, Kirizawa & Lopes 1874 (SP!); São Paulo, Itú, Ipanema, Kuhlmann s.n. (SP!); São Paulo, Jardim Público, 1892, Edwall s.n. (BR!); São Paulo, Jardim Botânico, 9 Sept. 1937, Handro s.n. (SP!). Rio de Janeiro: without precise locality, Glaziou 14294 (C!); Itatiaia, Sept. 1934, Brade 14001 (HB!, RB!); same area, Sept. 1913, Brade 8072 & Toledo s.n. (HB!); same area, Feb. 1899, Gounelle s.n. (G! — mixed collection with P. falcifolium); Nova Friburgo, Alto Macaé: Glaziou s.n. (BR!); Nova Friburgo, Macaé de Cima, Warren 93/8 (K! — spirit); near Nova Friburgo, 5 Nov. 1974, Dungs s.n. (HB!); Nova Frigurgo, Murí, Nov. 1965, Sick s.n. (HB!); Parati, 20 – 25 Sept. 1946, Berla s.n. (R!); Petrópolis, Oct. 1944, Góes & Dionísio 1127 (RB!); same area, Spannagel 10 (SP!); same area, 19 Nov. 1925, Hunnewell s.n. (AMES!); near Petrópolis, 19 Nov. 1925, Hunnewell 9870 (AMES!); same area, 23 Nov. 1946, Hunnewell 18483 (AMES!); Petrópolis, Mosela, 15 Nov. 1954, Egler 52 (RB!); Rio de Janeiro, without collector, from the “herbarium of the U.S. South Pacific Exploring Expedition 1833 – 1842” (AMES!); Rio de Janeiro, Glaziou 14294 (BR!); Pico da Tijuca, Sept. 1916, Hoehne 240 (SP!); Teresópolis, Feb.1888, Moura 101 (BR!); same area, Jan. – March 1888, Moura 2 (BR!); same area, Jan. – Feb. 1890, Moura 411 (BR!); Teresópolis, Fazenda Boa Fé, Velloso 181 (R!); Teresópolis, Serra dos Orgãos, 1838, Gardner 644 (G!, K!); same area, 1883, Schwacke s.n. (R!); same area, 5 Jan. 1883, Schwacke 4310 (BR!, RB!); same area, 22 Feb. 1887, Schenck 2645 (BR!); same area, Saldanha s.n. (R!) & Miers s.n. (US!, K!); same area, 1833, Vauthier 381 (G!); Teresópolis, Parque Nacional da Serra dos Orgãos, 11 Feb. 1952, Vidal II-5609 (R!); same area, fl. cult. 12 Dec. 1958, Abendroth P-127 (HB!); same area, 9 Jan. 1960, Flaster 47 (HB!). Minas Gerais: Pedra de Amolar, near Ouro Preto, Schwacke 8699 (RB!). Espírito Santo: Alfredo Chaves, near São Bento de Urânia, 19 Nov. 1987, Toscano de Brito 402 & Kautsky s.n. (HB!); Santa Teresa, Nova Lombardia, 28 Aug. 1985, Hoffman s.n. (MBML!). HABITAT. Epiphytic on small branches of shrubs and trees in forest. Also found in disturbed areas and orchards. Alt. 0 – 1400 m. ETYMOLOGY. The specific epithet derives from the Latin hysteranthus, meaning leaves produced later than the flowers. However, this phenomenon has not been reported in the genus Phymatidium. NOTES. Although similar in habit to Phymatidium aquinoi, P. hysteranthum is closely related to P. BRAZIL. A TAXONOMIC REVISION OF THE GENUS PHYMATIDIUM 543 A B C D E F H L M J N P K G Fig. 4. Phymatidium hysteranthum. A flower in front view; B flower in side view; C dorsal sepal; D petal; E lateral sepal; F lip; G column in side view with anther and pollinarium removed; H anther in side view; J pollinarium in front view; K pollinarium from behind; L habit; M – P variation in leaf transverse sections. A – F, G, L – P drawn from Warren 93/8 (K — spirit); H from Vauthier 381(G); and J – K from Hoffman s.n. (MBML). Single-line scale = 1 mm. Double-line scale = 1 cm. ALL DRAWN BY SUSANNA STUART-SMITH. © The Board of Trustees of the Royal Botanic Gardens, Kew, 2007 544 delicatum and its allies. The strongly reflexed sepals and arching petals together with column and anther morphology are very distinctive and readily separate it from all other species of Phymatidium. This species was misidentified as P. delicatum in Senghas (1995). 5. Phymatidium microphyllum (Barb. Rodr.) Toscano (2001: 211). Ornithocephalus microphyllus Barb. Rodr. (1877:134); Cogn. (1905: 234, pro. syn.). Type: Brazil, Minas Gerais, Caldas, Barbosa Rodrigues s.n. (Lost). Lectotype designated by Toscano de Brito (2001): Barbosa Rodrigues’ original illustration which appeared in his Iconographie des orchidées du Brésil, vol. 6, plate 314, fig. B (Library of Rio Botanical Garden!), reproduced in Sprunger et al. (1996: 442). Phymatidium delicatum auct. non Lindl. (1833): Cogn. (1905: 234, t. 56, f. 1, et spec. cit. in part.); Pabst & Dungs (1977: 324, f. 2197). Plant up to c. 20 mm tall, forming small to dense and intricate clumps. Roots several, terete, flexuous, thickish, papillose or glabrous. Stem inconspicuous. Leaves up to c. 26 × 1 mm, several, falcate, coriaceous, variable in cross-section, subterete, green. Inflorescences few to several, up to c. 90 mm long, 2- to 10-flowered, racemose, occasionally producing flowering plantlets; peduncle up to c. 45 mm long, slightly flexuous, angular in cross-section, finely papillose on the angles, covered by several widely spaced, narrowly ovate to linear sterile bracts, up to 8 × 0.5 mm, acute; rachis up to 45 mm long, zig-zag; floral bracts similar to the sterile ones, decreasing slightly in size towards the apex of inflorescence. Flowers usually resupinate, white with a green centre, with spreading segments or usually not opening widely, with sepals and petals cur ved for wards. Pedicel 2 – 4.5 mm long, slightly twisted, angled, shortly papillose on the angles. Ovary c. 0.5 – 1 mm long, obscurely angled. Dorsal sepal 2 – 3 × 0.3 – 1 mm, linear, narrowly ovate to oblonglanceolate, slightly hooded, acute, abaxially weakly carinate. Lateral sepals 2 – 2.5 × 0.5 mm, spreading or somewhat porrect and cur ved upwards, linear, narrowly ovate to ovate-lanceolate, falcate, usually slightly concave towards the apex, acute, abaxially weakly carinate. Petals 2.2 – 5 × 0.6 – 1.5 mm, KEW BULLETIN VOL. 62(4) spreading, ovate, narrowly ovate to ovate-lanceolate, rarely linear, weakly carinate abaxially, acute to obtuse and very shortly apiculate. Lip 2 – 5 × 1.5 – 3.5 mm, usually broadly unguiculate with a cordiform blade, rarely somewhat rhombic, slightly obtuse to acute, usually acuminate; margins usually weakly erose at the middle of the lip up to near the apex, entire towards the base; base provided with a glandular, concave, ligulate callus which is rounded at apex and equals or slightly exceeds the length of the claw of the lip. Column 1 – 2.5 mm long (excluding the tabula infrastigmatica), strongly incur ved, slightly to distinctly sigmoid, sulcate underneath, weakly to distinctly recurved near the apex, auriculate, the auricles somewhat semicircular to broadly ovate when spread, running from near the base up to the apex of the column, glabrous or inconspicuously papillose, the margins of the auricles entire, slightly sinuose to inconspicuously erose; stigmatic cavity small, ovate, placed at base of the column; rostellum very short to somewhat conspicuous, usually somewhat porrect and curved forwards; tabula infrastigmatica c. 1 – 1.6 × 1 – 1.6 mm, thick, swollen, somewhat obovate-trapeziform in outline from above, laterally sulcate, usually with a longitudinal obscurely raised ligulate or obovoid callus at the middle; anther c. 1.5 mm long, operculate, ovate-panduriform in outline, somewhat incur ved towards the apex, usually with a hint of a tooth at each side near the apex, which is shortly recur ved and emarginate; pollinia arranged in two superposed unequal pairs, the superior pair clavate, the inferior obovoid; stipe c. 1 mm long, cuneiform, base curved forward, the apex bifurcate or subtruncate and obscurely 3lobed; viscidium ver y small, broadly elliptic, concave. Capsule 3.5 – 5 × 3 – 5 mm, globose, obscurely carinate, the pedicel c. 2.5 mm long (P. microphyllum var. herteri). Fig. 5. The specific epithet derives from the Greek mikros, small, and phyllon, a leaf, and refers to the small size of the leaves. NOTES. Phymatidium microphyllum was first described in the genus Ornithocephallus by Barbosa Rodrigues in the first volume of his Genera et Species Orchidacearum Novarum published in 1877. In the second volume ETYMOLOGY. Fig. 5. A – H Phymatidium microphyllum var. microphyllum. A flower; B1 dorsal sepal; B2 lateral sepal; C petal; D – E Lip; F1 – F3 column variation; G1 anther in front view; G2 anther from behind; H1 – H4 pollinarium variation: H1 and H3 in front view, H2 and H4, from behind. A – D, F1, F3, G1 – G2 and H1 – H4 from Hatschbach 33631 (HB); E and F2 from Lindberg 543 (S). J – Q Phymatidium microphyllum var. herteri. J1 flower in front view; J2 flower in side view; K1 dorsal sepal; K2 lateral sepal; L petal; M1 – M3 lip variation; N1 column with auricle bent backwards to show rostellum; N2 apex of column showing auricles in place; P1 anther in side view; P2 anther in front view; Q1 – Q4 pollinarium variation: Q1 and Q3 from behind, Q2 and Q4 in front view. J – M1, N – P and Q3 – Q4 from Richter s.n. (HB58071); M2 from Reitz & Klein 10828 (HB); M3 from Hatschbach 2245 (MBM); Q1 and Q2 from Dusén 13878 (S). Line scale = 1 mm. ALL DRAWN BY SUSANNA STUART-SMITH. © The Board of Trustees of the Royal Botanic Gardens, Kew, 2007 A TAXONOMIC REVISION OF THE GENUS PHYMATIDIUM 545 B1 C A F1 B2 D F2 F3 G2 G1 E H1 H3 H2 H4 J2 J1 Q1 Q2 K1 M2 M3 L K2 N1 M1 P1 P2 Q3 Q4 N2 © The Board of Trustees of the Royal Botanic Gardens, Kew, 2007 546 published in 1882, he mistakenly treated this species as conspecific with P. delicatum. All subsequent authors have apparently followed Barbosa Rodrigues and thus a transfer of this species to the genus Phymatidium has only been recently made (Toscano de Brito 2001). P. microphyllum is indeed closely related to P. delicatum, from which it differs mainly in the shape of the column, especially the shape of the broader and longer auricles which are usually glabrous or rarely obscurely papillose. Like Phymatidium delicatum, P. microphyllum is quite a variable species and has some extreme variants which seem to be more or less reproductively isolated from the others. These are here recognised as P. microphyllum var. microphyllum and P. microphyllum var. herteri. 5a. var. microphyllum Plant usually forming small clumps. Roots papillose or glabrous. Leaves up to c. 10 × 1 mm. Inflorescences up to c. 60 mm long; peduncle up to c. 40 mm long; sterile bracts up to 5 × 0.5 mm; rachis up to 30 mm long, zig-zag; floral bracts similar to the sterile ones, decreasing slightly in size towards the apex of inflorescence. Flowers with spreading segments, sometimes the lateral sepals slightly curved inwards and upwards. Pedicel 2 – 3 mm long. Ovary c. 0.8 – 1 mm long. Dorsal sepal 2 – 3 × 0.3 – 1 mm, linear, ovate or lanceolate, slightly hooded. Lateral sepals 2 – 2.5 × 0.5 mm, usually spreading, linear, narrowly ovate to ovate-lanceolate, slightly falcate. Petal 2.2 – 5 × 0.6 – 1.5 mm, spreading, ovate, narrowly ovate to ovatelanceolate, rarely linear, acute to obtuse and very shortly apiculate. Lip 2 – 3.5 × 1.5 – 3.5 mm, usually broadly unguiculate with a cordiform blade, rarely somewhat rhombic, acute to slightly obtuse. Column 1 – 1.8 mm long (excluding the tabula infrastigmatica) slightly to distinctly sigmoid, weakly recurved near the apex; auricles somewhat semicircular to broadly ovate when spread, running from near the base up to the apex of the column; margins of the auricles entire or inconspicuously erose; rostellum weakly curved forwards; apex of stipe bifurcate. Capsule not seen. Fig. 5A – H. Brazil: Paraná and Minas Gerais. Paraná: without precise locality, 12 Dec. 1909, Lange s.n. (S! — mixed collection with P. delicatum var. curvisepalum) & Lange 7894 (HB! — mixed collection with P. delicatum); without precise locality and date, Dusén s.n. (S!); Quatro Barras, Borda do Campo, 4 Jan. 1974, Hatschbach 33631 (MBM!, HB!); Quatro Barras, Serrinha, 9 Dec. 1908, Dusén p.p.733 (S!); Taquari, 29 Jan. 1975, Ferreira 198 (MBM!, HB!); Tijucas do Sul, Saltinho, 28 Dec. 1958, Hatschbach 5396 (MBM!, HB!); DISTRIBUTION. BRAZIL. © The Board of Trustees of the Royal Botanic Gardens, Kew, 2007 KEW BULLETIN VOL. 62(4) Tijucas do Sul, Matulão, 1 Jan. 1964, Hatschbach 10871 (MBM!, HB!, B!). Minas Gerais: Caldas, Regnell ser. III. 1169 (S!); Caldas, near Rio Verdinho, 30 Nov. 1873, Mosén 742 (S!, SP!); Caldas, near Capivari, 5 – 19 Oct. 1854, Lindberg 543 (BR!, S!). HABITAT. Epiphytic on small branches of trees in Atlantic forest. Also found in disturbed areas and orchards. Alt. 900 – 1200 m. NOTES. This taxon has some variants which presents distinctive vegetative and floral morphology. One of these variants, found in the Municipality of Caldas, Minas Gerais, has papillose roots and a distinctive column with auricles running from near the base up to the top of the slightly sigmoid column. The name Ornithocephalus microphyllus was based on a specimen of this variant with unusually narrow tepals. It was illustrated by Cogniaux (1905: t.56, f. 1) as P. delicatum but based on Barbosa Rodrigues’ original drawing of Ornithocephalus microphyllus. Likewise, in Sprunger et al. (1996: 442) this illustration of O. microphyllum appeared named as Phymatidium delicatum. A second variant, recorded for the State of Paraná, has glabrous roots, more spreading and broader tepals, broader lip, and different auricles of the column. However, plants with intermediate floral morphology are recorded and based on the information available, I do not believe that this variant warrants formal taxonomic recognition. 5b. Phymatidium microphyllum var. herteri (Schltr.) Toscano (2001: 211). Phymatidium herteri Schltr. (1920: 450); Schltr.(1925: 102); Mansfeld (1930, t. 59, f. 236). Type: Brazil, Rio Grande do Sul, São Francisco de Paula, Herter 26245 (holotype B†). Phymatidum paranaense auct. non A. Samp. (1916): Pabst & Dungs (1977: 325, f. 2203). Plants usually forming dense and intricate clumps. Roots glabrous. Leaves up to c. 26 × 1 mm. Inflorescences up to c. 90 mm long; peduncle up to c. 45 mm long; sterile bracts 1.5 – 8 × 0.3 – 0.4 mm; rachis up to c. 45 mm long, slightly flexuous to zig-zag; floral bracts usually longer than the pedicellate ovary. Flowers not opening widely, with petals and sepals curved forwards. Pedicel 2 – 4.5 mm long. Ovary 0.5 – 0.8 mm long. Dorsal sepal 2.5 – 3.5 × 0.5 – 1 mm, narrowly ovate to oblong-lanceolate, slightly concave. Lateral sepals 2.6 – 4 × 0.5 – 1 mm, narrowly ovate to ovatelanceolate, distinctly falcate, usually somewhat porrect and curved upwards, slightly concave towards the apex. Petal 2.3 – 3.2 × 0.7 – 1.2 mm, narrowly ovate to somewhat lanceolate, curved forwards, acute. Lip 3 – 5 × 2 – 3.5 mm, unguiculate with cordiform blade, the claw of the lip usually cuneate, the apex acute, usually acuminate. Column 1.5 – 2.5 mm long (excluding the A TAXONOMIC REVISION OF THE GENUS PHYMATIDIUM tabula infrastigmatica), usually clearly sigmoid, usually distinctly recurved near the apex; auricles running from near the middle up to the apex of the column, usually somewhat quadrate when spread, with entire or slightly sinuose margins; rostellum usually somewhat porrect; apex of stipe subtruncate and obscurely 3-lobed to slightly bifurcate. Capsule 3.5 – 5 × 3 – 5 mm, globose, obscurely carinate, the pedicel c. 2.5 mm long. Fig. 5J – P. Brazil: Rio Grande do Sul, Santa Catarina and Paraná. BRAZIL. Rio Grande do Sul: Canela, 2 March 1963, Richter s.n. (HB!); Canela, near Canela, March 1953, Richter s.n. (HB!); same area, 2 July 1964, Richter s.n. (HB!); Taimbezinho, Bercker s.n. (HB!); São Francisco de Paula, Feb. 1946, Gliesch s.n. (PACA!); São Francisco de Paula, near São Francisco de Paula, 20 Feb. 1953, Rambo s.n. (PACA!); same area, 13 March 1950, Pabst 587 (HB!); São Francisco de Paula, Fazenda Englert, Jan. 1944, Buck s.n. (PACA!). Santa Catarina: Lages, Rodovia Federal Km 3, S of Lages, Smith & Klein 11290 (US!); São José, Serra da Boa Vista, 4 Feb. 1953, Reitz 5490 (HB!); same area, 2 March 1961, Reitz & Klein 10811 (HB!) & Reitz & Klein 10828 (HB!). Paraná: Antonina, Estrada Cacatú – Serra Negra, 19 Jan. 1966, Hatschbach 13561 (MBM!); Curitiba, 2 March 1912, Dusén 13878 (S!); Gal. Carneiro, Rio Lageado, 12 Feb. 1966, Hatschbach et al. 13856 (MBM!, HB!); Piraquara, Estrada da Graciosa, Alto da Serra, 22 April 1951, Hatschbach 2245 (MBM!, SP!); Quatro Barras, Morro Sete, 27 March 1990, Cervi 3064 & Ribas s.n. (MBM!); Quatro Barras, Rio do Corvo, 1 April, 1969, Hatschbach 21304 (MBM!); São Mateus, Gurgel — Instituto de Quimica 14641 (RB!); Guarapuava, Cachoeira dos Turcos, 13 Feb. 1969, Hatschbach 21177 (MBM!, HB!); São José dos Pinhais, Col. Roseira, 23 Feb. 1968, Koczicki 81 (MBM!, HB!). HABITAT. As for the typical variety. Alt. 800 – 1200 m. ETYMOLOGY. Named after Wilhelm Herter (1884 – 1958), who first collected this orchid in 1913. NOTES. This variety was first described as Phymatidium herteri by Schlechter in 1920 without any illustration. A drawing of P. herteri was only made available to the general public about 5 years after his death when a number of Schlechter’s original drawings of new species of orchids were published for the first time by Mansfeld in 1930. The type of Phymatidium herteri was apparently destroyed during the bombing of the Berlin herbarium during the Second World War. However, Schlechter’s drawings of P. herteri clearly show some of its main features, e.g., petals and sepals curved forwards giving the flower a somewhat closed appearance, falcate lateral sepals (which are usually curved upwards, but this is not shown on the drawing), and the usually cuneate claw of the lip. The drawing of DISTRIBUTION. 547 the column, although rather schematic, clearly shows a sigmoid column with auricles almost perpendicular to the rest of the column, apparently running from somewhere above the middle up to the top of the column. The pollinarium depicted in this drawing shows a feature, the stipe with an almost truncate apex, usually found in P. microphyllum var. herteri. Although the floral morphology of most specimens examined agrees well with Schlechter’s original drawings, I have been able to find intermediates between Phymatidium microphyllum var. microphyllum and P. microphyllum var. herteri. In some specimens the lip is intermediate in morphology; in others, the column morphology is intermediate. For example, the lip illustrated in Fig. 5M.1, of the present work is similar in shape to that in Schlechter’s original drawing of P. herteri; Fig. 5M.2, presents a lip closer to that of P. microphyllum var. microphyllum and Fig. 5M.3, shows an extreme variant of P. microphyllum var. herteri. The column of P. microphyllum var. herteri usually has a clearly recurved apex with auricles almost perpendicular to the rest of the column body, but here again variation exists and intermediates can be found. For instance, the specimen Mosén 742 (SP!, S!), here considered as belonging to P. microphyllum var. microphyllum, has lateral sepals and a column morphology intermediate between the latter and P microphyllum var. herteri. Nevertheless, the general floral morphology of this specimen is more like that of P. microphyllum var. microphyllum. Plants of P. microphyllum var. herteri usually form dense clumps, occasionally with quite long inflorescences, whereas P microphyllum var. microphyllum usually forms small clumps of very few plants and often has shorter inflorescences. But this also varies and cannot be used as a character to separate these two taxa at species level. I believe that some populations of P. microphyllum var. herteri are reproductively isolated and have a more uniform morphology, while others interbreed with the typical variety and intermediates are produced. Based on the information available, and until further research is carried out, I believe that the best way of treating P. herteri is as a variety of P. microphyllum. Phymatidium herteri was considered by Pabst (1957) to be conspecific with P. paranaense, here treated as a synonym of P. delicatum (see comments under P. delicatum). II. Phymatidium aquinoi Alliance The single species which comprises this alliance is characterised by the strongly sigmoid column which lacks a tabula infrastigmatica. The anther is longbeaked, operculate and incurved, with two lateral teeth near the obtuse to acute apex. The pollinarium is conspicuous by its comparatively long caudatespathulate stipe, which is attached to the pollinia © The Board of Trustees of the Royal Botanic Gardens, Kew, 2007 548 through a pair of lanceolate, flange-like caudicles. The auricles are reduced to 2 small flaps situated near the rostellum, the latter being usually deflexed or recurved and somewhat hooked. The stigmatic cavity is quite large for the genus and occupies almost a third of the column. The lip is ovate-lanceolate with entire margins and carries at the base a thick, glandular callus. The leaves are coriaceous, variable in cross-section, usually semi-terete to terete. 6. Phymatidium aquinoi Schltr. (1925: 101); Pabst (1953: 88); Pabst & Dungs (1977: 202, f. 2196). Types: Brazil, Rio Grande do Sul: near Torres, Burger (under Aquino 19) (syntype B†) & Santa Cruz, Herval de Baixo, Jürgens 74 (syntype B†). ?P. naviculare A. Samp. (1923: 28), nomen nudum. P. seehaweri I. Bock (1998b: 102, f.:103). Type. Brazil, Rio de Janeiro, Serra de Macaé de Cima, c. 1000 m, 1993, Seehawer s.n. (HAL). Plant up to c. 25 mm tall, usually forming a small clump. Roots many, terete, thickish, glabrous, flexuous. Stem up to c. 10 mm long, usually inconspicuous and branched at base. Leaves up to c. 30 × 1 mm, falcate, somewhat twisted, variable in cross-section both within the same specimen and leaf, 3-angled, semi-terete, oval to semi-oval, slightly sheathing and shortly decurrent at base, the apex acute. Inflorescences several, up to c. 110 mm long, fewto c. 10-flowered, racemose; peduncle up to c. 60 mm long, obliquely elliptic in cross-section, flexuous, covered by several, fleshy, falcate, narrowly ovatelanceolate to linear-subulate sterile bracts, up to c. 10 × 1 mm, acute, usually 3-angled in cross-section; rachis up to c. 50 mm long, usually zig-zag, obliquely elliptic in cross-section; floral bracts similar to the sterile ones, decreasing in size towards the apex of the inflorescence. Flowers usually resupinate, with spreading segments,usually with a white green column and callus on the lip, the latter having been reported to turn green after pollination. Pedicel c. 3.5 mm long, somewhat twisted, slightly angled, inconspicuosly papillose on the angles.Ovary c. 1.5 mm long, slightly angled. Dorsal sepal 3.5 – 5 × 0.7 – 1.3 mm, linear, oblong-lanceolate or narrowly ovatelanceolate, usually slightly recurevd, acute, abaxially slightly carinate. Lateral sepals 3.5 – 5 × 1 mm, obliquely oblong-lanceolate, falcate, somewhat waved and recurved, acute, abaxially slightly carinate. Petal 3 – 4.5 × 1 – 1.7 mm, obliquely broadly lanceolate, somewhat spreading, slightly waved and recurved, usually with a hump on the mid-vein near the base, acute, slightly carinate abaxially. Lip 4 – 5 × 2 – 2.5 mm, ovate-lanceolate, acute, deflexed; margins entire, somewhat waved; base provided with a large, thick, glandular within, concave, broadly ovate to © The Board of Trustees of the Royal Botanic Gardens, Kew, 2007 KEW BULLETIN VOL. 62(4) somewhat rounded callus, the apex of which is usually emarginate or bidentate. Column 2 – 2.5 mm long, lacking a tabula infrastigmatica, strongly sigmoid, slightly thicker towards the base, strongly incurved or geniculate at middle, and markedly recurved near the apex, sulcate underneath, very shortly auriculate at the level of the rostellum; auricles somewhat triangular when spread, curved outwards and backwards; stigmatic cavity large, ovate, placed at base and occupying a third of the column; rostellum short but quite distinctive, usually deflexed or recurved and somewhat hooked, flanked at base by two small teeth; anther 2.5 – 5 mm long, operculate, long and distinctly beaked, incurved, with a small tooth on each margin near apex, somewhat acute to obtuse; pollinia arranged in two superposed unequal pairs, the superior pair clavate, the inferior somewhat obovoid; stipe c. 2.5 mm long, narrowly caudate-spathulate, incurved towards the base, the apex somewhat rounded to subtruncate; viscidium small, somewhat ovate and slightly concave. Capsule immature, c. 3 × 2.5 mm, slightly obconoidal, somewhat 3-angled in cross-section or slightly 3keeled with alternating less pronounced ridges, the pedicel c. 3 mm long. Fig. 6. Brazil: Rio Grande do Sul, Santa Catarina, Paraná, and Rio de Janeiro. Menini Neto et al. (2003) reporded this species for the State of Minas Gerais, but so far I have been unable to confirm this information. BRAZIL. Rio Grande do Sul: Caxias do Sul, 3 Oct. 1951, Frank s.n. (PACA!); Canela, fl. cult. Dec. 1950, Richter 809 (AMES!); same area, Sept. 1950, fl. cult. Oct. 1950, Richter s.n. (HB!, RB!); same area, Richter s.n. (HB!); near Gramado, 28 Jan. 1963, Nelz s.n. (HB!); Nova Petrópolis, Frank s.n. (HB!). Santa Catarina: Biguami, Fachinal, 19 Jan. 1945, Reitz C949 (RB!); Vidal Ramos, Sabiá, 31 Dec. 1957, Reitz & Klein 5933 (HB!); same area, 28 Jan. 1958, Reitz & Klein 6320 (HB!). Paraná: Campina Grande do Sul, Jaguatirica, 22 Jan. 1960, Hatschbach 6674 (MBM!); Guaratuba, Col. Limeira, 29 Dec. 1971, Hatschbach 28593 (MBM!); Ipiranga, 1 Sept. 1910, Dusén 10183 (S!); Paranaguá, Pico Torto, 15 Jan. 1970, Hatschbach 23331 (MBM!); São José dos Pinhais, Col. Santos Andrade, 11 Dec.1986, Cordeiro 390 & Hatschbach s.n. (MBM!). Rio de Janeiro: Maringá, near Visconde de Mauá, Serra da Mantiqueira, near the boarder with Minas Gerais, 7 Sept. 1981, Toscano de Brito 190 (K! — spirit); Nova Friburgo, Macaé de Cima, Sítio Bacú, 26 Aug. 1987, Leitman et al. 272 (RB!); Nova Friburgo, Murí, 9 – 11 April 1982, Toscano de Brito 279 (K! — spirit); Petrópolis, fl. cult. 23 June 1992, cultivated at Orquidário Binot, Toscano de Brito 960 (K! — spirit); Nova Friburgo, Variante Nova, 1 April 1959, Duarte 4673 & Pereira s.n. (RB!); Nova Friburgo, Castelo do DISTRIBUTION. A TAXONOMIC REVISION OF THE GENUS PHYMATIDIUM 549 A B E C D J F L H K G Fig. 6. Phymatidium aquinoi. A dorsal sepal; B petal; C lateral sepal; D lip; E flower; F column in side view with anther and pollinarium removed; G apex of column with anther in place; H – J variation in anther morphology; K pollinarium in front view; L pollinarium from behind. A – F, H from Toscano de Brito 960 (K); G and J from Cordeiro 390 & Hatschbach s.n. (MBM); K – L from Reitz & Klein 5993 (HB). Line scale = 1 mm. ALL DRAWN BY SUSANNA STUART-SMITH. © The Board of Trustees of the Royal Botanic Gardens, Kew, 2007 550 Lopes, 4 June 1961, Pabst 5618 (HB!); Teresópolis, praça do Alto, 6 June 1958, Abendroth P-67 (HB!). HABITAT. An epiphyte on trees in wet places in Atlantic forest. Also found in disturbed and cultivated areas, especially on garden shrubs and trees. Alt. 300 – 1500 m. ETYMOLOGY. Named after Sr. Francisco Aquino from Porto Alegre, Brazil, who collaborated with Schlechter’s studies of the orchid flora of Rio Grande do Sul by sending him specimens for identification. NOTES. Phymatidium aquinoi is similar in habit to P. hysteranthum, but can be readily recognised by its unique floral morphology. The petals usually possess a hump on the mid-vein, the base of lip is provided with a broadly ovate to somewhat rounded, usually emarginate or bidentate, thick callus, the strongly sigmoid column lacks a tabula infrastigmatica and has a large stigmatic cavity, and the unusually deflexed and recurved rostellum makes the viscidium apparently face towards the centre of the flower and the ventral part of the column. The long-beaked anther and the pollinarium with its long stipe are also distinctive. The specimens collected by Burger and Jürgens upon which Schlechter based his description were probably destroyed during the bombing of the Berlin Herbarium during the Second World War. As Schlechter provided no illustration in his publication my identification of this species relies upon my interpretation of the original description. My conclusion is in agreement with Brade, Hoehne and Pabst, based on their identifications as Phymatidium aquinoi of herbarium specimens which I have examined. The first illlustration of Phymatidium aquinoi was provided by Pabst & Dungs (1977: 324, f. 2196) more than fifty years after Schlechter’s original description. This illustration is copy of a drawing made by Brade of a flower dissection of the specimen Richter s.n. (RB!), collected in Canela, Rio Grande do Sul State. Pabst & Dungs’ illustration and Brade’s original drawing, which is now kept at the Herbarium Bradeanum (HB) in Rio de Janeiro, show a lip with apical margins slightly hairy. I have boiled a flower of this specimen and have been unable to find any hairs on the apical margins of the lip. More recently, Bock (1998b) has illustrated and redescribed a collection of Phymatidium aquinoi as a new species, P. seehaweri I. Bock, mainly on the basis of absence of a hump on the petals, a non-bidentate lip callus, and entire lip. However, the specimens here studied have demonstrated that a hump may be present or absent on the petals of P. aquinoi and its lip callus may or may not be bidentate. Schlechter (1925) described the lip of this species as being 3lobed probably because his description was based on a spread lip and the basal, lateral lobes indicated by him are nothing else than the spread, flattened, © The Board of Trustees of the Royal Botanic Gardens, Kew, 2007 KEW BULLETIN VOL. 62(4) lateral portions of the lip callus. All specimens that I have examined, however, possess an entire lip. The name Phymatidium naviculare, which appeared in Sampaio’s list (1923) of the Orchidaceae preserved in the herbarium of the National Museum, Rio de Janeiro, has never been validly published. I have studied the collection cited by Sampaio (Sampaio 2328, R!). This has been named P. aquinoi by Pabst in the herbarium, but it lacks mature flowers so that confirmation is not possible. III. Phymatidium mellobarretoi Alliance This alliance comprises three interrelated species which all have a column with two lateral fleshy armlike appendages at the base, flanking the tabula infrastigmatica. These arms can be variable in shape within the same species and are sometimes reduced to a pair of small erect ears. The column is usually strongly incurved or geniculate in the middle, with the rostellum and clinandrium crowning it forming a more-or-less “T”-shape. The distinctively dorsal and somewhat recurved clinandrium bears the hooded and somewhat clavate anther. The apex of the column is ventrally prolonged into a usually 3-lobed rostellum. The rostellum lateral lobes may be much shorter, longer or as long as the midlobe. The pollinia are attached to the stipe through two pairs of lanceolate, flange-like caudicles. The leaves are coriaceous, usually semi-terete to terete. 7. Phymatidium limae Porto & Brade (1937: 137, t. 1 – 3); Pabst & Dungs (1977: 202, f. 2200. Type: Brazil, Rio de Janeiro, Santa Maria Madalena, Alto do Desengano, 3 March 1934, Santos Lima s.n. & Brade 13335 (holotype RB!). Plant 15 – 35 mm tall. Roots several, elongate, terete, thickish, glabrous, flexuous. Stem up to c. 3 mm long. Leaves up to 4 – 12 × 0.5 – 0.9 mm, erect, linearsubulate, semi-terete to oval in cross-section, slightly sheathing and obscurely decurrent at base, apex acute. Inflorescence up to c. 30 mm long, up to c. 6-flowered, racemose; peduncle c. 10 mm long, angular in crosssection, covered by few fleshy, falcate, slightly concave, triangular, subulate sterile bracts, up to c. 2.5 × 0.5 mm, acute; rachis c. 10 mm long, slightly flexuous, angular in cross-section; floral bracts similar to the sterile ones, decreasing slightly in size towards the apex of inflorescence. Flowers resupinate, not opening widely, diaphanous and snow-white. Pedicel c. 3 mm long, somewhat twisted, slightly angular, inconspicuously papillose on the angles. Ovary c. 0.6 mm long, angular in cross-section. Dorsal sepal 4.7 – 5 × 0.5 – 1.2 mm, narrowly lanceolate to narrowly ovatelanceolate, acute, abaxially weakly carinate. Lateral A TAXONOMIC REVISION OF THE GENUS PHYMATIDIUM sepals 5 – 6 × 0.8 – 1.2 mm, obliquely narrowly lanceolate or obliquely linear-ovate, falcate, acute, abaxially slightly carinate. Petal 4.5 – 5 × 1 – 1.4 mm, narrowly lanceolate, acute, abaxially slightly carinate. Lip 5.5 – 6.5 × 3 – 3.5 mm, rhombic, cuneate towards base, distinctly acuminate at apex; margins slightly erose at middle of the lip, becoming entire towards the base and the apex; base provided with a concave, broadly ligulate callus which is glandular within and somewhat recurved towards the apex; just beyond the 551 main callus of the lip there is an obscure hump or hint of a second callus. Column 1.5 mm long (excluding the tabula infrastigmatica), geniculate near the base, distinctly sigmoid at apex, sulcate underneath; stigmatic cavity somewhat elliptic, placed at the base of the column; rostellum 3-lobed, the lateral lobes much shorter than the middle one; tabula infrastigmatica c. 1.5 mm long, bearing a central, longitudinal, conspicuous callus which is somewhat nose-shaped in side view, elliptic or narrowly ligulate and slightly A L M N P D E C B H J F K G Fig. 7. Phymatidium limae. A dorsal sepal; B – C lateral sepals; D – E petals; F lip; G column, ovary and pedicel in side view with anther and pollinarium removed; H apex of column in side view showing anther-cap in place; J apex of column in side view with anther removed to show pollinarium; K apex of column in side view with anther and pollinarium removed; L anther with pollinarium still attached; M anther in side view; N pollinarium in front view; P pollinarium from behind (RB). Drawn from the holotype (Santos Lima s.n. & Brade 13335, RB). Line scale = 1 mm. DRAWN BY SUSANNA STUART-SMITH. © The Board of Trustees of the Royal Botanic Gardens, Kew, 2007 552 concave from above, flanked by a pair of sub-erect and spathulate arm-like appendages at base; anther c. 1.5 mm long, hooded, clavate, distinctly beaked and somewhat recurved towards the apex, acute; pollinia arranged into two superposed, usually slightly unequal pairs, clavate; stipe c. 1 mm long, slightly spathulate and convex, the base somewhat curved, the apex obtuse; viscidium small, elliptic, slightly concave. Capsule not seen. Fig. 7. Brazil: Rio de Janeiro. Rio de Janeiro, Santa Maria Madalena, Alto do Desengano, 3 March 1934, Santos Lima s.n. & Brade 13335 (holotype RB!). HABITAT. Epiphytic on trees in rain forest at higher altitudes. Alt. c. 1800 m. ETYMOLOGY. Named after Mr. J. Santos Lima who, together with Dr. A. C. Brade, collected the type specimen. NOTES. This species is closely related to Phymatidium mellobarretoi from which it may be distinguished by the shape of the lip, which has a cuneate base and lacks a lamella projecting beyond the main callus, and by the shape of the rostellum, which has two small, toothlike lateral lobes and a conspicuous middle one. The flowers of P. limae do not open widely in the type collection whereas in P. mellobarretoi the floral segments are always somewhat spread, the lateral sepals being strongly reflexed and the lip deflexed. Phymatidium limae is apparently a rare species and is known only from the type collection. The description provided here is based on the type material and original description. Some characters stated in the type description have been omitted because I have been unable to observe them. DISTRIBUTION. BRAZIL. 8. Phymatidium mellobarretoi L. O. Williams & Hoehne (1947: 92, t. 30); Pabst & Dungs (1977: 202, f. 2201); Miller & Warren (1996: 244, t. 32). Type: Brazil, Minas Gerais, Municipality of Aiuruoca, between Serra do Bispo and Serra da Cangalha, 20 June 1943, Mendes Magalhães 2849 (holotype SP!, isotype MO!). Plant up to c. 40 mm tall, usually forming an intricate clump. Roots many, scattered throughout the stem, KEW BULLETIN VOL. 62(4) terete, thick, glabrous, flexuous, usually quite long and forming an intricate clump of many roots. Stem up to c. 25 mm long, usually inconspicuous. Leaves up to c. 25 × 1 mm, falcate, somewhat twisted, semiterete to slightly 3-angled in cross-section at the middle, oval towards the apex, slightly sheathing and obscurely decurrent at base, the apex acute. Inflorescences few to several, up to c. 65 mm long, fewto c. 10-flowered, racemose; peduncle up to c. 25 mm long, 3-angled in cross-section, slightly zig-zag, covered by several fleshy, falcate, slightly concave, subulate sterile bracts, up to c. 5 × 0.5 mm, acute, more or less semi-terete in cross-section; rachis up to c. 40 mm long, usually slightly zig-zag, angular in cross-section; floral bracts similar to the sterile ones, decreasing in size towards the apex of inflorescence. Flowers usually resupinate, white with green centre. Pedicel 3 – 4 mm long, somewhat twisted, slightly angular, inconspicuously papillose on the angles. Ovary c. 0.5 mm long, obscurely angular. Dorsal sepal 3.5 – 4.5 × 0.5 – 1 mm, linear-lanceolate, narrowly ovate-lanceolate, usually inflexed and somewhat hooded, slightly concave, acute to slightly obtuse, abaxially weakly carinate. Lateral sepals 4 – 5 × 0.5 – 1 mm, obliquely linear-lanceolate or obliquely ovatelanceolate, falcate, strongly reflexed and usually curved upwards, acute to somewhat obtuse, abaxially slightly carinate. Petal 3 – 4.5 × 1 – 1.2 mm, linear, linear-lanceolate or narrowly ovate, usually inflexed or spreading and erect, acute to obtuse, abaxially slightly carinate. Lip 4.5 – 5 × 2.5 – 4 mm, strongly deflexed, somewhat panduriform, sub-quadrate towards the base, rhombic from the middle towards the apex, distinctly acuminate, rather convex; margins dentate, erose or crenulate at middle of the lip, becoming entire towards the base and the apex; base provided with a thick, concave, usually erect, broadly ligulate or broadly ovate callus which is glandular within and usually emarginate at apex, projecting beyond the main callus there is a fleshy, usually erect and cuneate lamella which is usually emarginate, erose or denticulate and retrorse at apex. Column 1.5 – 2 mm long (excluding the tabula infrastigmatica), strongly incurved or geniculate near the middle, distinctly sigmoid at apex, sulcate underneath; stigmatic cavity somewhat ovate to elliptic, placed at the base of the column; rostellum Fig. 8. Phymatidium mellobarretoi. A flower in side view; B dorsal sepal; C lateral sepal; D petal; E – F lip variation; G column in side view; H column and lip callus with anther and pollinarium removed; J column in side view; K column in side view with anther and pollinarium removed; L apex of column in front view with anther and pollinarium removed; M apex of column in side view with anther and pollinarium removed; N anther from behind with pollinarium still attached to it; P anther from behind; Q pollinarium in front view; R pollinarium from behind; S habit. A, H and S from Toscano de Brito 959 (K — spirit); B – E, G, L – R from Mello Filho 4086 & Emmerich 4273 (R); F from Catellanos s.n. (HB); J – K from Brade 20626 (RB). Single-line scale = 1 mm. Double-line scale = 1 cm. ALL DRAWN BY SUSANNA STUART-SMITH. © The Board of Trustees of the Royal Botanic Gardens, Kew, 2007 A TAXONOMIC REVISION OF THE GENUS PHYMATIDIUM 553 H G A J B D K L P M N C Q E F R S © The Board of Trustees of the Royal Botanic Gardens, Kew, 2007 554 occasionally entire, usually obscurely or distinctly 3lobed, the lateral lobes spathulate, somewhat diverging, usually exceeding in size the rostellum midlobe; tabula infrastigmatica c. 1.5 mm long, with a central, usually narrow and acute callus, nose-shaped in side view, adaxially convex, flat or slightly sulcate, and flanked at base by two lateral, fleshy auricles or arm-like appendages which are variable in shape and size; anther c. 1.5 mm long, narrowly ovate to somewhat clavate, hooded, distinctly beaked and somewhat recurved towards the apex, acute; pollinia arranged into two superposed, usually slightly unequal pairs, clavate; stipe c. 1 mm long, somewhat spathulate, slightly convex, the base somewhat curved, the apex obtuse; viscidium small, elliptic to ovate, slightly concave. Capsule c. 4 × 3 mm, subglobose, obscurely ridged, the pedicel c. 5 mm long. Fig. 8. Brazil: São Paulo, Rio de Janeiro and Minas Gerais. BRAZIL. São Paulo: Campos do Jordão, Pabst 345 (HB!); Campos do Jordão, Parque Estadual, 6 Nov. 1978, Emmerich s.n. (R!); same area, 18 March 1975, Mello Filho 4086 & Emmerich 4273 (R!); same area, 24 April 1982, Toscano de Brito et al. 292 (RB!); Serra da Bocaina, 19 April 1951, Brade 20626 (RB!); Serra da Bocaina, Alto da Boa Vista, 17 May 1951, Brade 20906 (R!); Serra da Bocaina, Reserva Florestal da Bocaina, 5 May 1968, Sucre et al. 2877 (RB!); same area, 8 May 1968, Sucre et al. 3039 (RB!); Serra da Bocaina, Lageado, Jan. 1957, Lutz s.n. (R!); Serra da Bocaina, Barreiro Co., Lageado Farm, March 1951, SegadasVianna 2801 (R!). Rio de Janeiro: Itatiaia, Planalto, March 1937, Brade 15687 (RB!); Nova Friburgo, Alto Macaé, April 1993, Miller s.n. (K! — spirit). Minas Gerais: Itamonte, Estrada Nova Km 1, 25 March 1942, Brade 17249 (RB!); Passa Quatro, Pico do Muro, 5 May 1948, Brade 18995 & Araújo s.n. (RB!); Serra da Mantiqueira, between Serra Negra and Mauá, Morro Cavado, May 1962, Castellanos s.n. (HB!); Aiuruoca, between Serra do Bispo and Serra da Cangalha, 20 June 1943, Mendes Magalhães 2849 (holotype SP!, isotype MO!). HABITAT. Epiphytic on trees in the rain forest at higher altitudes. Alt. 1400 – 2000 m. ETYMOLOGY. Named after Dr. Henrique Mello Barreto. NOTES. Phymatidium mellobarretoi can easily be recognised by its lip and column morphology. The distinctive panduriform lip has a peculiar lamella which projects beyond the main callus of the lip, while the usually geniculate column shows a strongly sigmoid apex, a character also shared by P. limae and P. vogelii. The apex of the column is extended into a conspicuous, usually 3-lobed rostellum. The tabula infrastigmatica is quite variable in shape; in some DISTRIBUTION. © The Board of Trustees of the Royal Botanic Gardens, Kew, 2007 KEW BULLETIN VOL. 62(4) specimens the median, longitudinal callus is very narrow and acute, while in others it is thick and obtuse. At the base of the tabula infrastigmatica, near the stigmatic cavity, there are two fleshy, erect appendages which are also variable in size and shape. In most specimens studied, these look like erect ears flanking the central callus at the base (Fig. 8G – H), whereas in others they are narrower and have an arm-like shape (Fig. 8J – K) similar to those found on the tabula infrastigmatica of P. limae. In Brade 20626 (RB), the rostellum is entire (Fig. 8K), while the two appendages on the tabula infrastigmatica are also arm-like in shape. The column morphology of this specimen seems to be intermediate between P. mellobarretoi and P. limae, the latter having the rostellum lateral lobes reduced to two small teeth and the two lateral appendages on the tabula infrastigmatica shaped like arms. Nevertheless, all its other floral segments are like those of P. mellobarretoi. 9. Phymatidium vogelii Pabst (1972: 173, t. 3, f. C); Pabst & Dungs (1977: 202, f. 2205). Type: Brazil, São Paulo, Serra da Bocaina, 14 March 1965, Vogel 806 (holotype HB!). Plant small, delicate, c. 20 mm tall. Roots elongate, thickish, terete, filiform, glabrous, flexuous. Stem inconspicuous. Leaves c. 25 × 0.4 mm, linear, subterete, slightly sheathing at the base, the apex acute. Inflorescence c. 40 mm long, 4- to 5-flowered, loose, racemose; peduncle c. 15 mm long, angular in crosssection, obscurely flexuous, covered by few lineartriangular, acute sterile bracts, c. 5 × 0.25 mm; rachis c. 35 mm long, slightly zig-zag, angular in cross-section; floral bracts similar to the sterile ones, decreasing slightly in size towards the apex of inflorescence. Flowers greenish-white. Ovary pedicellate, c. 5 mm long, slightly twisted, angular, obscurely papillose. Dorsal sepal c. 3.5 × 0.5 mm, narrowly lanceolate, acute, abaxially obscurely carinate. Lateral sepals c. 3.5 x 0.5 mm, narrowly ovate-lanceolate, slightly oblique and falcate, acute, abaxially obscurely carinate. Petal c. 3.2 × 0.7 mm, lanceolate, acute, abaxially slightly carinate. Lip c. 3.5 × 1.6 mm, ovate-lanceolate, somewhat acuminate, the margins entire, the base provided with a small, concave, ligulate callus which is slightly emarginate at the apex. Column c. 1 mm long (excluding the tabula infrastigmatica), slightly incurved, somewhat sigmoid near the apex, beaked, sulcate underneath, base obscurely hairy (fide original description); rostellum conspicuous, entire, slightly curved forwards; stigmatic cavity not seen; tabula infrastigmatica very small, somewhat swollen and thickish, obtuse, flanked at base by a pair of short, suberect, ear-like appendages at base; anther relatively A TAXONOMIC REVISION OF THE GENUS PHYMATIDIUM 555 large, c. 1 mm long, hooded, clavate, distinctly beaked and somewhat recurved towards the apex, acute; pollinarium not seen. Capsule not seen. Fig. 9. Brazil: São Paulo. Epiphytic, in shade, on trunks of Podocarpus lambertii Klotzsch ex Endl., on the plateau of Serra da Bocaina in the State of São Paulo. Alt. c. 1500 m. ETYMOLOGY. Named after Dr Stefan Vogel, who collected the type specimen. NOTES. The only material of Phymatidium vogelii known to the author is the type specimen, which is very delicate and unfortunately has been very badly pressed. The leaves and flowers are rather flattened which precluded a proper study. However, the floral morphology of this species is that of the P. mellobarretoi Alliance, notably the column shape and the two lateral ear-like appendages flanking the tabula infrastigmatica at the base. The clinandrium is dorsal and somewhat recurved and the rostellum is conspicuous and entire. The anther is operculate and relatively large. Phymatidium vogelii is closely related to P. mellobarretoi and P. limae from which it can be distinguished by the floral morphology, especially the size and the shape of the lip. The illustration (Fig. 9) in the present work is based on Pabst’s original drawing of a floral dissection of the holotype. DISTRIBUTION. HABITAT. A D E B C F Fig. 9. Phymatidium vogelii. A dorsal sepal; B – C lateral sepals; D – E petals; F lip. Drawn after Pabst’s original drawings of the holotype (Vogel 806, HB). Line scale = 1 mm. DRAWN BY SUSANNA STUART-SMITH. IV. Phymatidium falcifolium Alliance This alliance comprises a single unusual species, Phymatidium falcifolium, which has soft, slightly fleshy, dorsiventrally flattened, bifacial leaves. The stems are proliferous and usually elongate. The column is wingless, somewhat clavate and has a relatively large, broad and somewhat 3-lobed tabula infrastigmatica. The lip has adaxially a rather large, concave, glandular callus which occupies most of the lip surface. The anther is ovate and operculate with a very shortly recurved and emarginate apex. The pollinia are attached to a pair of cupulate caudicles on the top of the stipe. 10. Phymatidium falcifolium Lindl. (1833: 210); Cogn. (1905: 236); Pabst & Dungs (1977: 202, f. 2198); Toscano (2001: 172, f. 6 – 7 &: 212, f. 30). Type: Brazil, without precise locality, Prescott s.n. (holotype K!). Phymatidium tillandsioides Barb. Rodr.(1882: 228); Barb. Rodr. (1882: 294); Cogn. (1905: 235, t. 49, f. 2 ); Schltr. & Hoehne (1926: 294 ); Herter (130: 52); Hoehne (1949: 231, t. 286, f. 2); Teucher (1965: 221 ); Pabst & Dungs (1977: 202, f. 2204); Karasawa (1989: 275, photo 257); Senghas in Brieger (1995: 1903, f. 1862); Miller & Warren (1996: 245, t. 40). Type: Brazil, Paraná, Serra de Sant’Anna and Serra da Prata, Barbosa Rodrigues s.n. (Lost). Lectotype, here designated: Barbosa Rodrigues’ original illustration which appeared in his Iconographie des orchidées du Brésil, vol. 6, plate 316 (Library of Rio de Janeiro Botanical Garden!), reproduced in Sprunger et al. (1996: 444). Phymatidium delicatum auct. non Lindl. (1833): Senghas in Brieger (1995: 1901, f. 1859). Phymatidium lopesii Ruschi (1969: 1). Type: Brazil, Espírito Santo, Santa Teresa, córrego Paulo Miranda Ribeiro, Ruschi 6210 (holotype MBML!spirit). Plant up to c. 100 mm tall, usually forming dense clumps. Roots many, terete, flexuous, glabrous. Stem up to c. 100 mm long, terete, ascending, branched. Leaves up to c. 7 × 1.5 mm wide (c. 4 mm across the base), many, in a dense spiral along the stem, conduplicate, falcate, soft, slightly fleshy, arching, somewhat twisted, shortly carinate abaxially, slightly concave, ovate, sheathing and shortly decurrent at base, becoming somewhat linear-caudate toward the apex, acuminate, pale-green. Inflorescences few, up to c. 100 mm long, few (c. 2) to many-flowered (c. 10), racemose; peduncle up to c. 40 mm long, angular in cross-section, covered by a number of widely spaced, decurrent, narrowly ovate-lanceolate sterile bracts, c. 4 × 1 mm; rachis up to c. 70 mm long; floral bracts © The Board of Trustees of the Royal Botanic Gardens, Kew, 2007 556 similar to the sterile ones. Flowers not resupinate, white with green centre and spreading segments. Pedicel c. 4 mm long, twisted, angular, usually bent near the apex. Ovary c. 1 mm long. Dorsal sepal c. 3 × 1 mm, oblong-lanceolate, acute to obtuse, abaxially slightly carinate, white. Lateral sepals c. 3.5 × 1 mm, obliquely ovate-lanceolate to oblong-lanceolate, acute to obtuse, abaxially, slightly carinate, white. Petals c. 3.2 × 1.5 mm, oblong, slightly ovate or oblonglanceolate, acute to obtuse, abaxially slightly carinate, white. Lip c. 3 × 2 mm, slightly ovate, oblong or slightly obovate when spread, white, provided adaxially with a large, concave, auriculate-ovate callosity which is densely glandular within and occupies c. 3/4 of the lip surface, the lateral margins are deflexed, erose, lacerate or denticulate, whereas the front margins are smoother and usually undulate or obscurely denticulate. Column c. 1.5 mm long (excluding the tabula infrastigmatica), incurved, somewhat clavate in side view, sulcate underneath, wingless, white; stigmatic cavity small, ovatelanceolate, placed at the base of the column, ovatelanceolate; rostellum very short, curved forwards; tabula infrastigmatica c. 1.5 × 2 mm, conspicuous, solid, thick, shiny green, somewhat 3-lobed and reniform when spread and seen from above, with a raised, convex, obovoid, conspicuous callus at the middle; anther c. 1.5 × 1 mm, operculate, ovate in outline, the apex shortly emarginate and slightly recurved; pollinia arranged in two superposed unequal pairs, the superior pair obovoid, the inferior slightly globose; stipe c. 1 mm long, cuneiform, curved forwards at base, the apex truncate to obscurely trilobed bearing two small, cupulate sockets; viscidium very small, concave, slightly oblong with a broader, rounded apex. Capsule c. 4.5 × 4 mm, subglobose, the pedicel c. 3 mm long. Fig. 10. Brazil: Santa Catarina, Paraná, São Paulo, Rio de Janeiro, and Espírito Santo. Herter (1930) reported this species for Uruguay, but so far I have been unable to confirm this information. BRAZIL. Without precise locality: fl. cult. Berlin-Dahlem Botanic Garden, 9 Aug. 1990, Cubr 27307 (B); fl. cult. July 1968, Teuscher s.n. (HB!); Prescot s.n. (holotype K!); Edwall s.n. (SP!). Santa Catarina: Araranguá, Meleiro, 25 Jan. 1944, Reitz C412 (RB!, AMES!) & Reitz 1060 (PACA!); Blumenau, Schwacke 5506 (RB!, BR!); Blumenau, 1884, Schwacke 58 (col. IV) (RB!); Blumenau, 4 Dec. 1886, Schenck 379; Ibirama, Horto DISTRIBUTION. KEW BULLETIN VOL. 62(4) Florestal I.N.P., 23 May 1956, Klein 2035 (HB!); Brusque, Morro Spitzkopf, 14 Feb. 1951, Reitz 3699 (HB!); Isle of Santa Catarina, without precise locality, Schreiner s.n. (R!); same area, Müler s.n. (R!); Isle of Santa Catarina, Florianópolis, 1942, Rohr s.n. (PACA!); same area, Jan. 1940, Rambo s.n. (PACA!); Isle of Santa Catarina, Morro do Ribeirão, 14 Feb. 1967, Klein 7172 (MBM!, HB!); Isle of Santa Catarina, Morro Costa da Lagoa, 13 Feb. 1969, Klein & Bresolin 8185 (HB!); Isle of Santa Catarina, Ribeirão, 27 Jan. 1951, Rohr 2063 (HB!, K!); Isle of Santa Catarina, Sertão da Lagoa, Jan. 1954, Rohr s.n. (B!); Itajaí, Canhanduva, 11 Jan. 1966, Rebello s.n. (HB!). Paraná: without precise locality, Dusén s.n. (S!); Antonina, 15 Jan. 1976, Hatschbach 37949 (MBM); Guaratuba, Rio Saí, 17 Jan. 1970, Hatschbach 23350 (MBM!, C!, HB!, NY!); Serra de Araraquara, Morro do Cauvi, 30 Dec. 1963, Hatschbach 11060 (MBM!, B!); Paranaguá, Picadão Cambará-Col. Limeira, 14 Feb. 1968, Hatschbach 18606 (MBM!); Morretes, Usina Elétrica Marumbi, 4 Jan. 1966, Hatschabach et al. 13415 (MBM!, HB!, F!); Morretes, Col. Floresta, 24 Jan. 1969, Hatschbach 20923 & Koczicki s.n.(MBM!); Morretes, Porto de Cima, 21 Jan. 1914, Dusén 14301 (AMES!, S!); same area, 4 Jan. 1975, Dziewa 140 (MBM!); Morretes, Serra da Prata, 25 Feb. 1911, Dusén 11778-A (S!) & Dusén 11778 (S!); near Morretes, Sapintanduva Biological Reserve, 29 Jan. 1985, Lewis et al. 1401 (MBM!, K!). São Paulo: Alto da Serra, 26 March 1907, Usteri s.n. (K!); Alto da Serra, Biological Station, 14 Feb. 1922, Gehrt s.n. (NY!); same area, 10 June 1936, Herter 97952 (G!); same area, Loefgren, Comiss. Geogr. Geol. São Paulo 3281 (BR!); same area, July 1898, Edwall, Comiss. Geogr. Geol. São Paulo 4038 (BR!); Cubatão, 22 Dec. 1826, Burchell 3692 (K!) & Burchell 3728-2 (K!); Iguápe, Morro das Pedras, 18 Jan. 1920, Brade 8073 (HB!); Mogi das Cruzes, Borracéia, 16 Jan. 1941, Lima s.n. (RB!); Mogi das Cruzes, Borracéia Biological Station, 26 Jan. 1961, Eiten & Eiten 2515 (SP!, US!); São Paulo, Jardim Botânico, 10 Feb. 1938, Handro s.n. (SP!); São Paulo, Serra do Mar, Campo Grande, near São Paulo, 26 April 1915, Brade 7555 (HB!). Rio de Janeiro: without precise locality, 1891, Glaziou 18538 (C!, K!) & Jan. 1881, Glaziou 12209 (C!, K!) & fl. cult. Bigmel s.n. (K!) & fl. cult. 10 Sept. 1902, Royal Botanic Gardens, Glasnevin, Dublin, Binot s.n. (K!) & Langsdorff s.n. (Rio de Janeiro?) (BR!) & Campos Porto s.n. (RB!); Itatiaia, Feb. 1889, Gounelle s.n. (G! — mixed collection with P. hysteranthum); Sampaio 4063 (R) & Sampaio 4162 (R!); Itatiaia, 29 March 1974, Windisch s.n. (HB!); Itatiaia, Fig. 10. Phymatidium falcifolium. A flower; B dorsal sepal; C lateral sepal; D petal; E lip; F Column in side view; G apex of column in side view with anther and pollinarium removed; H anther in front view; J anther from behind; K pollinarium in front view; L pollinarium from behind; M habit; N leaf. Drawn from Warren 85/21 (K — spirit). Single-line scale = 1 mm. Double-line scale = 1 cm. DRAWN BY SUSANNA STUART-SMITH. © The Board of Trustees of the Royal Botanic Gardens, Kew, 2007 A TAXONOMIC REVISION OF THE GENUS PHYMATIDIUM 557 B A D E C F H G K J M N L © The Board of Trustees of the Royal Botanic Gardens, Kew, 2007 558 Mont Serrat, 23 July 1902, Dusén 722 (R!); Itatiaia, Lote 25, 23 Feb. 1936, Brade 15076 (RB!); Itatiaia, Lote 88, 1 March 1945, Segadas Vianna 722 (R!); same area, 8 Feb. 1942, Brade 17162 (RB!, HB!); Itatiaia, Rio Campo Belo, Feb. 1945, Brade 17532-A (RB!, HB!); Itatiaia, Picada Wettstein, 15 Feb. 1958, Emmerich 44 (R!); Nova Friburgo, Beyrich s.n. (K!); Nova Friburgo, Alto Macaé, Warren 85/21 (K! — spirit); Petrópolis, March 1927, Spannagel 59 (SP!); Petrópolis, Pati de Alferes Forest Reserve, 5 May 1972, Braga et al. 2480 (RB!, HB!); Petrópolis, Rocio, 27 Jan. 1968, Sucre 2228 & Braga 86 (RB!); same area, 28 Jan. 1968, Sucre 2249 & Braga 108 (RB!, HB!, NY!); Petrópolis, Serra das Araras, 1 April 1959, Duarte 4661 & Pereira s.n. (RB!, HB!); Petrópolis, Quitandinha, 10 Aug. 1939, Lutz 1470 (R!); same area, 21 March 1939, Lutz 1349 (R!); Serra da Estrela, Feb. 1915, Diogo 791 (R!); Santa Maria Madalena, 2 March 1935, Santos Lima s.n. & Brade 14311 (RB!); Teresópolis, Moura 87 (AMES!, BR!); same area, Jan. 1883, Moura 54 (BR!); same area, 15 Jan. 1883, Saldanha 6873 (RB!, R!); same area, fl. cult. Sept. 1917, Sampaio 2062-B (R!); same area, Dec. 1896, Ule 4119 (R!, BR!); same area, 21 Jan. 1951, Sohara s.n. (HB!); same area, Dec. 1962, Strang s.n. (HB!); Teresópolis, Serra dos Orgãos, Miers s.n. (K!); same area, Miers 3475 (K!); same area, Feb. 1837, Gardner 645 (S!, K!, US!, NY!, G!); same area, Schwacke 4814 (BR!); same area, 28 Feb. 1887, Schenck 2916 (BR!); 30 Jan. 1946, Pereira s.n. (HB!); same area, without collector (AMES!); Teresópolis, Serra dos Orgãos, estrada para Fazenda Jacarandá, 26 Dec. 1965, Pabst 8733 (F!, HB!, NY!, K!); Teresópolis, Serra dos Orgãos, Soberbo, fl. cult. 12 Dec. 1958, Abendroth P-128 (HB!). Espírito Santo: Forno Grande, 23 Jan. 1973, Lagasa 118 (MBML!); Santa Teresa, córrego Paulo Miranda Ribeiro, Ruschi 6210 (MBML! — spirit, holotype of P. lopesii). HABITAT. Epiphytic, usually on trees and shrubs near river margins and waterfalls in the forest. Alt. 0 – 1000 m. ETYMOLOGY. The specific epithet derives from the Latin falx, a scythe or sickle, and folium, a leaf, in reference to the shape of the leaves. NOTES. Examination of the type of Phymatidium falcifolium has proved that this species and the wellknown P. tillandsioides Barb. Rodr. are conspecific. The reason for these two species having been kept separated for more than a century is most probably because of a floral analysis which Lindley drew on the type sheet of P. falcifolium in his herbarium at Kew. This rather schematic drawing shows clearly but mistakenly a narrowly unguiculate lip, different column morphology and a convex, rather than concave, callus on the lip. Lindley had apparently little material of this species and his drawing seems to have been based on dried, pressed flowers. I have dissected and drawn a flower from the type specimen and it agrees well with the material of P. tillandsioides. © The Board of Trustees of the Royal Botanic Gardens, Kew, 2007 KEW BULLETIN VOL. 62(4) Because of its habit, which resembles some of the dwarf species of the genus Tillandsia L. (Bromeliaceae), Phymatidium falcifolium can be easily recognised. It is common in the Atlantic forest of Brazil and is widely cultivated. When compared with other members of Phymatidium, this species presents unique features. It is the only species with conduplicate leaves and has distinctive leaf anatomy (Toscano de Brito 1998) and seed morphology (Toscano de Brito 1999). Its floral morphology is also quite different, especially the large callus, which occupies almost three-quarters of the lip surface. This species was misidentified as P. delicatum in Senghas (1995: 1901, f. 1859). Examination of the type specimem of P. lopesii Ruschi has confirmed the view of Pabst & Dungs (1977), who considered it conspecific with P. falcifolium. Acknowledgements I thank Phillip Cribb (K) for improvements and commenting on an earlier draft of this manuscript, Susanna Stuart-Smith for preparing the drawings, the Amazon Trust of the Margaret Mee Fellowship Programme, England, and its Brazilian sister foundation, Fundação Botânica Margaret Mee, for their financial assistance for a visit to the herbarium of the Royal Botanic Gardens, Kew, in 1998, and the Royal Botanic Gardens, Kew, for providing funds for a recent visit to England, which enabled the conclusion of this work. References Barbosa Rodrigues, J. (1877). Genera et Species Orchidearum Novarum, Vol. 1. C. & H. Fleiuss, Rio de Janeiro. —— (1882). Genera et Species Orchidearum Novarum,Vol. 2. Sebastianopolis, Rio de Janeiro. Bentham, G. (1881). Notes on Orchideae. Bot. J. Linn. Soc.18: 281 – 360. —— (1883). Orchideae. In G. Bentham and J. D. Hooker, Genera Plantarum, Vol. 3, Part 3: 460 – 636. L. Reeve & Co. and Williams & Norgate, London. Bock, I. (1998a). Phymatidium hysteranthum. Orchidee (Hamburg) 49, orchideenkartei: 873 – 874. —— (1998b). Phymatidium seehaweri Bock, eine neue Art aus Brasilien. Orchidee (Hamburg) 49: 102 – 104. Chase, M. W. (1999). Molecular systematics, parsimony, and orchid classification. In: A. M. Pridgeon, P. J. Cribb, M. W. Chase & F. N. Rasmussen (eds.), Genera Orchidacearum, Vol. 1: 80 – 88. Oxford University Press. Cogniaux, A. (1904 – 1906). Orchidaceae. In: C. F. P. Martius, A. G. Eichler & I. Urban, Flora Brasiliensis, Vol. 3, Part 6. Munich & Leipzig. A TAXONOMIC REVISION OF THE GENUS PHYMATIDIUM —— (1907). Notes sur les orchidées du Brésil et des régions voisines. Bull. Soc. Roy. Bot. Belgique 43: 266 – 356. Endlicher, S. (1836 – 1937). Genera Plantarum Secundum Ordines Naturales Disposita, Parts 2 – 3. Fr. Beck Universitalis-Buchandlung, Vienna. Herter, W. (1930). Flora Uruguayensis Plantae Vasculares. Montevideo. Hoehne, F. C. (1949). Iconografia de Orchidaceas do Brasil. Secretaria de Agricultura, São Paulo. Jonhson, A. E. (2001). Las Orquídeas del Parque Nacional Iguazú. L.O.L.A. Buenos Aires. Karasawa, K. (1989). Orchid Atlas, Vol. 7, Oncidium, Miltonia. Orchid Atlas Publishing Society. Tokyo. Kerchove de Denterghem, O. de (1894). Le Livre des Orchidées. Ad. Hoste, Gand. Kraenzlin, F. (1911). Beiträge zur orchideenflora südamerikas. Kongl. Svenska Vetensk. Acad. Handl. 46: 1 – 105. Langsdorff, G. H. von. (1813). Voyages and Travels in Various Parts of the World During the Years 1803, 1804, 1805, 1806, and 1807. Henry Colburn, London. Lindley, J. (1830 – 1840). The Genera and Species of Orchidaceous Plants. Ridgways, London. Mansfeld, R. (ed.) (1930). Blütenanalysen neuer Orchideen von R. Schlechter — I. Südamerikanische Orchideen. Feddes Feddes Repert. Spec. Nov. Regni Veg. Beih. 58, t. 1 – 60. Meisner, C. F. (1842). 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Bradea 1: 165 – 173. —— & Dungs, F. (1977). Orchidaceae Brasilienses, Vol. 2. Brucke-Verlag Kurt Schmersow, Hildesheim. 559 Pfitzer, E. (1889). Orchidaceae. In: A. Engler & K. Prantl, Die natürlichen Pflanzenfamilien 11 (6): 52 – 224. Wilhelm Engelmann, Leipzig. Porto, P. C. & Brade, A. C. (1937). Orchidaceae Novae Brasilienses II. Arq. Inst. Biol. Veg. 3: 131 – 139. Ruschi, A. (1969). Orquidáceas novas do Est. do Espírito Santo. Bol. Mus. Biol. Prof Mello -Leitão, Ser. Bot., 26: 1 – 4. —— (1976). Orquidáceas novas do Est. do Espírito Santo. Bol. Mus. Biol. Prof Mello -Leitão, Ser. Bot., 85: 1 – 4. Sampaio, A. J. (1916). Plantae novae vel minus cognitae — I. Orchidaceae. Arq. Mus. Nac. Rio de Janeiro 18: 57 – 63. —— (1923). Lista das Orchidaceas do Herbario da Secção de Botanica do Museu Nacional. Museu Nacional, Rio de Janeiro. Schlechter, R. (1920). Orchidaceae novae et criticae. Feddes Repert. Spec. Nov. Regni Veg. Beih. 16: 437 – 450. —— (1925). 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Leaf anatomy of Ornithocephalinae (Orchidaceae) and related subtribes. Lindleyana 13: 234 – 258. —— (1999). Seed morphology of subtribes Ornithocephalinae and Telipogoninae (Maxillarieae: Orchidaceae). Lindleyana 14: 27 – 37. —— (2001). Systematic review of the Ornithocephalus Group (Oncidiinae; Orchidaceae) with comments on Hofmeisterella. Lindleyana 16: 157 – 217. Urban, I. (1906). Vitae itineraque collectorum botanicorum. In: C. F. P. von Martius, A. G. Eichler & I. Urban (eds.), Flora Brasiliensis, Vol. 1, part 1: 1 – 154. Munich and Liepzig. Warming, E. (1884). Symbolae ad floram Brasiliae centralis cogynoscendam, part. 9: 841 – 847. © The Board of Trustees of the Royal Botanic Gardens, Kew, 2007 560 Williams, C. A., Toscano de Brito, A. L. V. , Harborne, J. B., Eagles, J. & Waterman, P. G. (1994). Methylated C-glycosylflavones as taxonomic markers in orchids of the subtribe Ornithocephalinae. Phytochemistry 37: 1045 – 1053. Williams, L. O. & Hoehne, F. C. (1947). Uma nova espécie de Phymatidium do Brasil. Arq. Bot. Estado São Paulo 2: 92. Appendix List of Species, Varieties and Synonyms of Phymatidium (Accepted names are given in bold type). P. aquinoi Schltr. P. delicatum Lindl. P. falcifolium Lindl. P. geiselii Ruschi P. glaziovii Toscano P. herteri Schltr. = P. microphyllum var. herteri P. hysteranthum Barb. Rodr. P. limae Porto & Brade P. lopesii Ruschi = P. falcifolium P. mellobarretoi L. O. Williams & Hoehne P. microphyllum (Barb. Rodr.) Toscano P. microphyllum (Barb. Rodr.) Toscano var. herteri (Schltr.) Toscano P. myrtophilum Barb. Rodr. = P. delicatum P. naviculare A. Samp., nom. nud. = ? P. aquinoi P. paranaense A. Samp. nomen nudum = ? P. delicatum P. seehaweri I. Bock = P. aquinoi P. tillandsioides Barb. Rodr. = P. falcifolium P. vogelii Pabst Excluded Species P. antioquiense P. Ortíz = Eloyella antioquiensis (P. Ortíz) P. Ortíz P. cundinamarcae P. Ortíz = Eloyella cundinamarcae (P. Ortíz) P. Ortíz P. panamense Dressler = Eloyella panamensis (Dressler) Dodson © The Board of Trustees of the Royal Botanic Gardens, Kew, 2007 KEW BULLETIN VOL. 62(4)