Annals of Botany 104: 387 –402, 2009
doi:10.1093/aob/mcp067, available online at www.aob.oxfordjournals.org
Floral convergence in Oncidiinae (Cymbidieae; Orchidaceae): an expanded
concept of Gomesa and a new genus Nohawilliamsia
Mark W. Chase1,*, Norris H. Williams2, Aparacida Donisete de Faria3, Kurt M. Neubig2, Maria do Carmo
E. Amaral4 and W. Mark Whitten2
1
Jodrell Laboratory, Royal Botanic Gardens, Kew, Richmond, Surrey TW9 3DS, UK, 2Department of Natural History, Florida
Museum of Natural History, University of Florida, Gainesville, FL 32611-7800, USA, 3Instituto Nacional de Pesquisas da
Amazônia, Coordenação de Pesquisas em Botânica, Caixa Postal 478, 69054-335, Manaus, AM, Brazil and 4Departamento do
Botânica, Instituto de Biologia, Caixa Postal 6109, Universidade Estadual de Campinas – UNICAMP, 13083-970 Campinas,
SP, Brazil
Received: 20 October 2008 Returned for revision: 26 November 2008 Accepted: 27 February 2009 Published electronically: 4 April 2009
† Background Floral morphology, particularly the angle of lip attachment to the column, has historically been the
fundamental character used in establishing generic limits in subtribe Oncidiinae (Orchidaceae), but it has also
been long recognized that reliance on this character alone has produced a highly artificial set of genera. In
essence, lip/column relationships reflect syndromes associated with pollinator preferences; most genera of
Oncidiinae as previously defined have consisted of a single floral type. Here, the degree to which this has influenced generic delimitation in Brazilian members of the largest genus of Oncidiinae, Oncidium, which previous
molecular (DNA) studies have demonstrated to be polyphyletic, is evaluated.
† Methods Phylogenetic analyses of the following multiple DNA regions were used: the plastid psbA-trnH intergenic spacer, matK exon and two regions of ycf1 exon and nuclear ribosomal DNA, comprised of the two internal
transcribed spacers, ITS1 and ITS2, and the 5.8S gene. Results from all regions analysed separately indicated
highly similar relationships, so a combined matrix was analysed.
† Key Results Nearly all species groups of Brazilian Oncidium are only distantly related to the type species of the
genus, O. altissimum, from the Caribbean. There are two exceptions to this geographical rule: O. baueri is related
to the type group and O. orthostates, an isolated species that lacks the defining tabula infrastigmata of Oncidium,
is not exclusively related to any previously described genus in the subtribe. Several well-supported subclades can
be observed in these results, but they do not correspond well to sections of Oncidium as previously circumscribed
or to segregate genera as defined by several recent authors. In spite of their floral differences, these groups of
Oncidium, formerly treated as O. sections Barbata, Concoloria pro parte, Crispa, Ranifera, Rhinocerotes,
Rostrata (only O. venustum), Synsepala, Verrucituberculata pro parte and Waluewa, form a well-supported
clade with Gomesa (including Rodrigueziella and Rodrigueziopsis) embedded in it. Two often recognized segregate genera, Baptistonia and Ornithophora, and the recently described Carriella are also embedded within
the Brazilian clade. The level of variation within major subclades of the Gomesa clade is low and similar to
that observed within other genera of Oncidiinae.
† Conclusions Convergence on a stereotypical syndrome of floral traits associated with pollination by oilcollecting bees has resulted in these characters not being reliable for producing monophyletic taxa,
and the genus Oncidium, defined by these characters, is grossly polyphyletic. Vegetative and a few floral/
inflorescence characters link these taxa with a mainly Brazilian distribution, and they were all transferred
to Gomesa on this basis rather than separated from Gomesa based on their floral differences, which we
hypothesize to be simple shifts in pollination strategies. Other authors have described a large number of
new genera for these former members of Oncidium, but most of these are not supported by the results presented here (i.e. they are not monophyletic). A new genus, Nohawilliamsia, is described for O. orthostates
because it does not fit in any currently recognized genus and is only distantly related to any other member of
Oncidiinae.
Key words: Baptistonia, Brazilian orchids, Carriella, deceit pollination, Gomesa, ITS, matK, oil-collecting
bees, Oncidium, Oncidiinae, Orchidaceae.
IN T RO DU C T IO N
Oncidium Sw. (Oncidiinae; Cymbidieae; Orchidaceae) is one
of the most conspicuous genera of neotropical orchids. Their
mostly bright-yellow flowers often marked with brown are
* For correspondence. E-mail: m.chase@kew.org.uk
commonly called lluvia de oro (golden rain) in Spanish or
‘dancing ladies’ in English. They are mostly epiphytic and frequently seen in cultivation. In its broadest circumscription,
Oncidium has over 400 species. Delimitation of Oncidium
and related genera has been the subject of much controversy
and inconsistency (Dressler and Williams, 1975; Garay and
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388
Chase et al. — Phylogenetics of Gomesa (Oncidiinae)
Stacy, 1974). In simplest terms, Oncidium has always been a
genus of convenience, but if a set of circumscribing characters
were to be proposed these would include: a spurless (nonrewarding) flower with the lip (labellum) attached at a 908 or
greater angle to the column and a complex tuberculate callus
and tabula infrastigmatica (a fleshy structure on the base of
the column; Fig. 1). Given the clear arbitrariness of the
primary character, that of the angle of lip/column attachment
and heterogeneity of vegetative traits and chromosome
numbers in Oncidium when circumscribed using this character
(Chase, 1986, 1987), no one was at all surprised that the early
restriction endonuclease studies of plastid DNA showed that
Oncidium was polyphyletic (Chase and Palmer, 1992).
Subsequent studies of plastid and nuclear DNA sequences
(Williams et al., 2001a, b) have further detailed the extent
of problems with delimitation of Oncidium, and the process
of generic recircumscription to achieve monophyly has been
started, resulting in the description of Cyrtochiloides
A
dorsal sepal
anther cap
lateral petal
stigmatic cavity
tabula infrastigmatica
lip callus
lip
lateral sepal
B
anther cap
viscidium
stigmatic cavity
tabula infrastigmatica
F I G . 1. Floral morphology of Gomesa (Oncidium/Klaberiella) longipes
(Oncidiinae; Orchidaceae). This species has been treated as a member of O.
section Barbata (Garay and Stacy, 1974) and has a synsepal that is fused to
about one-third of its length. Scale bars: 0.5 cm (upper), 0.1 cm (lower).
(Drawing: Rodrigo B. Singer).
N.H.Williams & M.W.Chase and Zelenkoa M.W.Chase &
N.H.Williams, resurrection of Cyrtochilum Kunth, and expansion of Caucaea Schltr., Miltonia Lindl., Otoglossum Garay &
Dunsterville and Trichocentrum Poeppig & Endl. We have
also amalgamated into Oncidium the other genera of
Oncidiinae that are embedded in that clade; these include
Cochlioda, Odontoglossum and Symphyglossum (Chase
et al., 2008). This is the fourth installment of a series of
papers recircumscribing genera in Oncidiinae. Here the focus
is on the Brazilian species that have previously been included
in Oncidium.
In their synopsis of Oncidium, Garay and Stacy (1974)
recognized several sections of O. subgenus Oncidium that
were either endemic to Brazil (often most diverse in the
Mata Atlantica vegetation) or had their greatest species
diversity there. These include nearly all sections of the
genus with a synsepal (fused lateral sepals): O. sections
Barbata Lindl., Concoloria Kraenzl. pro parte, Crispa
Rchb.f., Rhinocerotes Garay & Stacy, Synsepala Pfitzer and
Waluewa (Regel) Schltr. In addition, some species of O.
section Paucituberculata Lindl., which some authors have
recognized as O. section Ranifera Kraenzl., also have a synsepal. Garay and Stacy (1974) also included in O. section
Paucituberculata species with thickened leaves and reduced
pseudobulbs, such as O. hians Lindl., that are morphologically
similar to the species of O. section Pulvinata, the Brazilian
mule-ear species of Oncidium (named for their long, flat,
thickened leaves and reduced pseudobulbs; these species are
now placed in Grandiphyllum Docha Neto) that have entirely
free lateral sepals. Species of O. section Ranifera (e.g.
O. raniferum Lindl., O. paranaense Kraenzl. and O. hookeri
Rolfe) have larger pseudobulbs (relative to their size) and
thin leaves compared with O. hians.
Some species of O. section Verrucituberculata Lindl., such
as O. batemanianum Parm ex Knowl. & Westc., have a synsepal and are principally distributed in Brazil, whereas others
lack the synsepal and are found outside of Brazil (e.g.
O. auriferum Rchb.f. from Colombia). The key character of
O. section Verrucituberculata (sensu Garay and Stacy) is the
presence of a few tubercles isolated on the lip away from the
main callus, but these species are otherwise similar to
species in other sections of the genus. Oncidium section
Concoloria also contains some non-Brazilian species, such
as O. hyphaematicum Rchb.f. and O. brachyandrum Lindl.,
that lack a synsepal but do have the section-defining lip
without lateral lobes and an even number of parallel tubercles.
Another ‘odd-ball’ Brazilian species, O. venustum Drapiez
(synonym O. trulliferum Lindl.), is vegetatively similar to
the members of O. section Waluewa, but it lacks the floral
traits typical of this group (a pilose column and synsepal). It
was treated as a member of O. section Rostrata by Garay
and Stacy (1974) because it has a beaked column, but it is
out of place in this group vegetatively and geographically (it
is the sole species of this section found in Brazil). Chiron
(2008) recently transferred this species to Baptistonia.
In addition, there are a number of other principally Brazilian
genera that have a synsepal; these are Baptistonia Barb.Rodr.
(monospecific or recently with additional species transferred
from Oncidium; Chiron and Castro Neto, 2004), Binotia
Rolfe (monospecific), the newly described Carriella
Chase et al. — Phylogenetics of Gomesa (Oncidiinae)
V.P.Castro & K.G.Lacerda (monospecific; Castro and Lacerda,
2005, 2006), Gomesa Lindl., Ornithophora Barb.Rodr. (monospecific), Rodrigueziella Kuntze (synonym Theodorea
Barb.Rodr. non Cass.; two species) and Rodrigueziopsis
Schltr (two species). Both Coppensia Dumort. and Waluewa
Regel were based on species with a synsepal, and these
species were included by Garay and Stacy (1974) in O. sections Synsepala and Waluewa, respectively. A synsepal is relatively rare in Oncidiinae outside Brazil, but this trait does
appear in Caucaea Rchb.f. (Andes), Symphyglossum Schltr.
(Andes), Systeloglossum Schltr. (Andes to Central America)
and Tolumnia Raf. (Caribbean), which were found in previously published studies not to be related to the Brazilian
groups with this trait (Williams et al., 2001a, b). In addition
to a synsepal, the Brazilian groups fold the perianth parts differently in the bud (the lip is often pushed through the tepals
before they unfold), hold their buds on a flexed rather than
straight pedicle and have a different inflorescence structure
in which the bracts (one at each node) are not closely held
to the developing raceme, such that their tips project
outward and away from the apex of the raceme, whereas in
groups of Oncidium related to the type species, tips of these
bracts are tightly appressed to the emerging raceme. These
traits also vary among species, and ones such as the protruding
lip are much more pronounced in species with large lips, such
as O. varicosum Lindl. and O. insigne (Rolfe) Christenson.
Most Brazilian groups also have a glaucous cast to their
leaves so that even in the vegetative state most species can
be separated from those of Oncidium proper.
All these differences from the type group of Oncidium, which
is diverse in Andean South America, Central America, the
Caribbean and Mexico rather than Brazil, had been previously
noted, but the floral morphology of all groups included in
Oncidium is more or less stereotypical, mostly bright yellow
with brown spotting/bars on sepals and petals with the typical
lip/column arrangement. The Brazilian groups also have the
most common chromosome number in Oncidium and
Oncidiinae, 2n ¼ 56, but they were known not to produce
hybrids when crossed to other sections of the genus (Sanford,
1964, 1967). However, interfertility is not useful in determining
generic limits in Orchidaceae, as Garay and Stacy (1974)
pointed out: ‘The fact that one Oncidium species will or will
not cross with another Oncidium species is quite inconsequential as far as this whole alliance is concerned, for genetic
compatibility among species is the rule rather than the exception
in the entire orchid family. The mere placing of a pollinium from
a given plant onto the stigma of another does not convey any
information to the vector whether it be a human being or a
member of the insect world.’
In earlier studies (Williams et al., 2001a, b), two approaches
were used to investigate generic relationships in Oncidiinae:
(1) a combined data set of all DNA regions from the plastid
and nuclear genomes; and (2) separate analyses of each
region to determine if they produce congruent results. The
first matrix was assembled to provide well-supported (by the
bootstrap; Felsenstein, 1985) estimates of relationships
because none of the individual matrices on their own provided
enough variable sites to obtain clear patterns. This same procedure is used in this paper but to matK are added three
other plastid regions, two portions of the highly variable
389
ycf1 gene (50 and 30 , 1098 and 1569 bp, respectively) and the
psbA-trnH spacer, to further increase the number of variable
sites included in analyses.
M AT E R I A L S A N D M E T H O D S
Total DNA was extracted from fresh or silica-gel dried
samples of leaves or flowers (Chase and Hills, 1991) using a
modified 2X CTAB protocol (Doyle and Doyle, 1987),
except that some of the samples were purified by caesium
chloride/ethidium bromide density-dependent centrifugation
(1.5 g mL21). All samples were vouchered by herbarium
specimens or pickled flowers (Appendix).
Production of DNA sequences for matK and ITS used protocols and primers described in Williams et al. (2001a) and
Whitten et al. (2000). Primers and protocols for ycf1 and
psbA-trnH are described in Neubig et al. (2009) and Xu
et al. (2000), respectively. Raw electropherograms were
assembled and checked for agreement of both strands using
Sequencher 4.8 (Genecodes, Inc.). Sequences were aligned
manually in PAUP* version 4.0b10 (Swofford, 2001) following the guidelines for insertion of gaps described by
Kelchner (2000). No computer algorithm is capable of estimating insertion/deletion events for the different categories of
change in DNA sequences; only the human eye can accomplish this task, so no computerized algorithm was used to
align the sequences. Data matrices are available from
M.W.C. and N.H.W. upon request (m.chase@kew.org;
orchid@flmnh.ufl.edu); all sequences have been deposited in
GenBank (Appendix).
Parsimony analyses
The following heuristic tree search strategy in PAUP* was
used for all analyses. In a first phase, 1000 replicates of
random-taxon entry order were used with tree-bisectionreconnection (TBR) swapping and a tree limit of ten trees
per step to eliminate having to swap on large numbers of
trees. The shortest trees found in these 1000 replicates were
then used as starting trees in another round of swapping with
no tree limit, and all shortest trees found were swapped on
to completion. To produce estimates of internal support, 500
replicates of the bootstrap were used with the following settings: simple addition, TBR swapping and a tree limit of ten
trees per step. The bootstrap consensus tree and one of the
individual trees with branch lengths proportional to the
amount of change are illustrated.
Searches were performed on three matrices: (1) a combined
plastid matrix for 60 taxa for which all data were present for all
taxa (Fig. 2A; but Cariella colorata Königer & J.G.Weinm.bis
is missing 50 ycf1); (2) ITS for 59 taxa (Gomesa handroi
(Hoehne) Pabst was missing for ITS; Fig. 2B); and (3) a combined matrix of for all 60 taxa (G. handroi and G. colorata for
which ITS and 50 ycf1 were coded as missing data, respectively). For plastid regions, there are no reasons to expect
incongruence for different parts of that non-recombining, uniparentally inherited genome so these were directly combined
without performing separate analyses. For the various parts
of the ITS/5.8S nrDNA region, a similar argument can be
made, although it is possible for other portions of the large
390
A
Chase et al. — Phylogenetics of Gomesa (Oncidiinae)
B
Plastid
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57
96
61
94
100
97
99
84
95
100
98
97
100
99
86
98
100
100
78
10 changes
83
100
63
100
64
100
100
57
100
54
99
60
72
100
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86
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100
100
100
97
95
96
90
Gomesa (Coppensia) pirarensis
Gomesa (Coppensia) hydrophila
Gomesa (Coppensia) spiloptera
Gomesa (Coppensia) warmingii
Gomesa (Coppensia) warmingii
Gomesa (Coppensia) barbaceniae
Gomesa (Coppensia) viperina
Gomesa (Coppensia) flexuosa
Gomesa (Rhinocidium) macronyx
Gomesa (Coppensia) welteri
Gomesa (Coppensia) varicosa
Gomesa (Coppensia) varicosa
Gomesa (Menezesiella) ranifera
Gomesa (Menezesiella) hookeri
Gomesa (Carenidium) dasytyle
Gomesa (Carenidium) concolor
Gomesa (Brasilidium) forbesii
Gomesa (Brasilidium) imperatoris-maximiliani
Gomesa (Brasilidium) praetexta
Gomesa (Ornithophora) radicans
Gomesa planifolia
Gomesa crispa
Gomesa recurva
Gomesa sessilis
Gomesa chrysostoma
Gomesa (Rodrigueziella) gomezoides
Gomesa glaziovii
Gomesa (Rodrigueziella) handroi
Gomesa (Rodrigueziopsis) eleutherosepala
Gomesa (Baptistonia) lietzil
Gomesa (Baptistonia) widgrenii
Gomesa (Baptistonia) echinata
Gomesa (Baptistonia) sarcodes
Gomesa (Baptistonia) kautskyi
Gomesa (Baptistonia) pubes
Gomesa (Baptistonia) venusta
Gomesa (Carriella) colorata
Gomesa (Alatiglossum) ciliata
Gomesa (Alatiglossum) barbata
Gomesa (Kleberiella) longipes
Gomesa (Alatiglossum) macropetala
Gomesa (Neoruschia) cogniauxiana
Gomesa (Carenidium) gracilis
Warmingia eugenii
Rodriguezia lanceolata
Comparettia falcata
Zelenkoa onusta
Nohawilliamsia orthostates
Tolumnia henekenii
Erycina hyalinobulbon
Otoglossum chiriquense
Cyrtochilum serratum
Oncidium wydleri
Oncidium altissimum
Oncidium pictum
Oncidium maculatum
Oncidium hastatum
Oncidium gheisbreghtianum
Oncidium oblongatum
Oncidium durangense
ITS
100
99
100
62
82
69
100
100
67
95
98
100
98
95
10 changes
99
63
60
82
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74
56
F I G . 2. Comparison of bootstrap consensus trees from separate plastid (A) and nr ITS (B) analyses; bootstrap percentages greater than 50 are indicated above
branches. Single trees with proportional branch lengths (DELTRAN optimization) are illustrated in the uppermost corners to demonstrate low levels of divergence
within some clades. Alternative recent circumscriptions are indicated in brackets. The type species of Oncidium s.s. is O. altissimum (seventh species from the
bottom).
ribosomal subunit to exhibit differential patterns of inheritance, e.g. in Caulerpa (Durand et al., 2002) and Drosophila
(Polanco et al., 1998). Direct combination of the plastid and
nuclear ribosomal regions and their degree of congruence in
Oncidiinae have been covered in Williams et al. (2001a, b).
No cases of strongly supported incongruence that could be
attributed to genealogical discordance were detected here
(Fig. 2), so direct combination is appropriate. The positions
of Oncidium (Carenidium) gracile Lindl. are discordant in
the plastid and ITS results, but there was no strong support
for its position in either analysis.
RES ULT S
Due to similarity of the separate ITS and plastid trees (Fig. 2),
with the noted exception only relationships observed
in the combined analysis (Fig. 3) will be described. The
ITS matrix had 869 characters, of which 212 (24 %) were
potentially parsimony-informative; the 17 ITS trees had 750
steps with a consistency index (CI) of 0.59 (including
autapomorphies) and a retention index (RI) of 0.77. The combined plastid matrix had 5184 characters, of which 445 (9 %)
were potentially parsimony-informative; the seven plastid trees
had 1677 steps with a CI of 0.68 and an RI of 0.79. Analysis of
the combined matrix produced three trees of 2464 steps with a
CI of 0.65 and an RI of 0.77. The species representing
Oncidium sections Barbata, Concoloria, Crispa, Ranifera,
Rhinocerotes, Synsepala and Waluewa (sections are indicated
to the right of the cladogram; Fig. 3) and most of the
Brazilian species of Verrucituberculata form a clade [100 %
bootstrap percentage (BP)] in which Baptistonia, Carriella,
Gomesa, Ornithophora, Rodrigueziella and Rodrigueziopsis
are embedded (Fig. 3). The larger clade is well supported
(100 BP) as distinct from the type section of Oncidium (the
Chase et al. — Phylogenetics of Gomesa (Oncidiinae)
66
95
98
92
98
100
98
100
70
100
100
86
92
100
98
79
100
100
97
100
100
66
63
69
51 100
100
100
100
100
99
100
60
57
99
99
100
93
72
91
98
100
100
100
76
90
96
95
Gomesa pirarensis
Gomesa hydrophila
Gomesa spiloptera
Gomesa warmingii
Gomesa barbaceniae
Gomesa warmingii
Gomesa viperina
Gomesa flexuosa
Gomesa macronyx
Gomesa welteri
Gomesa varicosa
Gomesa varicosa
Gomesa ranifera
Gomesa hookeri
Gomesa radicans
Gomesa dasytyle
Gomesa concolor
Gomesa forbesii
Gomesa imperatoris-maximiliani
Gomesa praetexta
Gomesa planifolia
Gomesa crispa
Gomesa recurva
Gomesa sessilis
Gomesa gomezoides
Gomesa glaziovii
Gomesa handroi
Gomesa chrysostoma
Gomesa eleutherosepala
Gomesa sarcodes
Gomesa lietzil
Gomesa widgrenii
Gomesa echinata
Gomesa pubes
Gomesa kautskyi
Gomesa colorata
Gomesa venusta
Gomesa ciliata
Gomesa barbata
Gomesa macropetala
Gomesa longipes
Gomesa cogniauxiana
Gomesa gracilis
Warmingia eugenii
Rodriguezia lanceolata
Comparettia falcata
Zelenkoa onusta
Nohawilliamsia orthostates
Erycina hyalinobulbon
Tolumnia henekenii
Otoglossum chiriquense
Cyrtochilum serratum
Oncidium wydleri
Oncidium altissimum – Type sp.
Oncidium pictum
Oncidium maculatum
Oncidium hastatum
Oncidium gheisbreghtianum
Oncidium oblongatum
Oncidium durangense
O. sect. Synsepala
O. sect. Ranifera
Ornithophora
O. sect. Concoloria
O. sect. Crispa
Gomesa s.s. +
Rodrigueziella
Gomesa s.l.
52
Gomesa pirarensis
G. hydrophila
G. spiloptera
G. barbaceniae
G. warmingii
G. warmingii
G. viperina
G. flexuosa
G. macronyx
G. welteri
G. varicosa
G. varicosa
G. ranifera
G. hookeri
G. radicans
G. dasytyle
G. concolor
G. forbesii
G. imperatoris-maximiliani
G. praetexta
G. planifolia
G. crispa
G. recurva
G. sessilis
G. gomezoides
G. glaziovii
G. handroi
G. chrysostoma
G. eleutherosepala
G. sarcodes
G. lietzii
G. widgrenii
G. echinata
G. pubes
G. kautskyi
G. venusta
G. colorata
G. ciliata
G. barbata
G. macropetala
G. longipes
G. cogniauxiana
G. gracilis
10 changes
391
Rodrigueziopsis
O. sect. Crispa
O. sect. Waluewa
O. sect. Rostrata
O. sect. Barbata
O. sect. Concoloria
Oncidium s.s.
F I G . 3. Bootstrap consensus tree from the combined analysis of plastid and nrITS DNA; bootstrap percentages greater than 50 are indicated above branches.
A single tree with proportional branch lengths (DELTRAN optimization) is illustrated in the upper left-hand corner to demonstrate low levels of divergence
within some clades. Previously recognized genera and the sectional classification of sensu Garay and Stacy (1974) are indicated by the bar on the right. The
type species of Oncidium s.s. is O. altissimum (seventh species from the bottom).
type is the Caribbean species, O. altissimum Sw.; Figs 2
and 3), and species representing other major clades of
Oncidiinae are well supported in intercalating positions.
In Fig. 2, the generic assignments of these taxa in the system
of Docha Neto et al. (2006) and Chiron and Castro Neto
(2004) are indicated in brackets. Baptistonia may be
392
Chase et al. — Phylogenetics of Gomesa (Oncidiinae)
monophyletic if Carriella is sister to the rest of the species
(but it is unresolved in our analyses; Figs 2 and 3), but none
of the other recently described genera with two or more
species is monophyletic. The sections of Oncidium sensu
Garay and Stacy (1974) are indicated on Fig. 3; none is monophyletic; if Baptistonia echinata Barb.Rodr., O. venustum
Drapiez and O. sarcodes Lindl. (section Crispa) are included,
O. section Waluewa is monophyletic. There are few differences in the ITS and plastid sequences between species in
this clade, e.g. the sequence for B. echinata is identical to
that of Oncidium lietzei Regel and Oncidium widgrenii
Lindl. Similarly low levels of variation are observed within
several other species clusters: these are centred around
Coppensia barbaceniae (Lindl.) Campacci, Coppensia varicosa (Lindl.) Campacci, Rhinocidium macronyx (Rchb.f.)
Baptista and Brasilidium crispum (Lodd.) Carpacci
[¼Anettea imperatoris-maximiliani (Rchb.f.) Szlach. &
Mytnik.].
DISCUSSION
Nearly all species of Oncidiinae are pollinated by insects that
receive no reward for visiting these plants ( pollinator relationships are reviewed by Chase in Pridgeon et al., 2009).
Exceptions are the members of the twig epiphyte clade,
many of which have a spur or cavity into which nectar is
secreted by a horn at the base of the lip or simply the lip
base itself (e.g. Comparettia Poeppig & Endl., Rodriguezia
Ruiz & Pavón and Leochilus Knowles & Westc.). Floral
fragrances may be collected from some genera by male euglossine bees (e.g. Notylia Lindl.). Some taxa in the Brazilian
group (e.g. species of O. sections Ranifera, Rhinocerotes and
Waluewa) appear to produce varying amounts of oil on the
lip callus, which may be collected by Centris bees that mix
it with pollen collected from other species and feed it to
their larvae (no orchid pollen has ever been observed to be
used in this manner; van der Pijl and Dodson, 1966). There
is sufficient oil present on lips of some species to collect it
with a capillary tube (Faria, 2004), and thus it is possible
that this is offered as a reward for pollination. In many
Oncidium species, we question whether there is sufficient oil
present to function as anything other than an attractant, in
which case this would be another instance of deceit pollination, but this situation requires further study. The structure of
the oil present in these species has been worked out to be
acylglycerols in Oncidium pubes Lindl. and free fatty acids,
non-volatile isoprenoids (triterpene squalene) and steroids
(stigmasterol and clionasterol) in O. flexuosum Sims (Reis
et al., 2000; Faria, 2004). Studies in the field are needed to
characterize this pollination syndrome more accurately.
Other research (Powell, 2008) has shown that the yellowflowered species with typical Oncidium morphology (regardless of whether they are members of type group of Oncidium
or the Gomesa clade) have floral UV-absorption patterns that
mimic those of similarly coloured species of Malpighiaceae,
which have sepalar glands that produce oil collected by
Centris bees. No other yellow flowers have been shown to
have this same pattern of light absorbance (Powell, 2008).
Thus, we may have a continuum of taxa that mimick
malpigh flowers in colour but offer no reward to some that
appear to be producing enough oil to reward a pollinator.
Some of the latter, such as O. raniferum Lindl., are not the
typical ‘malpigh yellow’, but UV absorption patterns in
these species have yet to be studied. Observations of oil bees
visiting Oncidium species (reviewed in van der Cingel,
2001) have recorded that these bees use their mandibles to
grab the tabula infrastigmatica and then attempt to scrap oil
from the lip callus with their legs, paralleling the situation in
malpigh species in which bees use their mandibles to hold
onto the banner petal (the one at 908 to the rest of the
petals) and scrape oil from sepalar glands with their legs.
This observation explains the presence of the tabula infrastigmatica, which otherwise appears to be an enigmatic structure
of Oncidium.
In any case, the typical malpigh-mimicking species of
Oncidiinae have floral traits associated with Oncidium, and
thus it is clear that Oncidium as a genus has historically
been defined by a floral syndrome related to its pollination
biology. It should therefore come as no great surprise that
such floral traits are subject to convergence, and the taxa
they characterize are unlikely to be monophyletic. Given that
these species are all members of a single subtribe and
closely related, then such convergence would be difficult to
separate from cases in which similarity of floral morphology
was due to common ancestry. Floral traits in Oncidiinae
should largely be ignored when considering generic limits,
and instead chromosome number and vegetative characters
should be emphasized. For example, when identifying the
species to be circumscribed into a resurrected concept of
Cyrtochilum (Williams et al., 2001a), floral traits had to be
disregarded; these had led previous taxonomists [e.g. Garay
and Stacy (1974) among many] to place these species in
several genera (e.g. Buesiella C.Schweinf., Oliveriana
Rchb.f., Oncidium and Odontoglossum Kunth). Instead, we
emphasized vegetative traits, in this case pseudobulbs that
were round in cross-section (rather than laterally compressed
as in most Oncidiinae) with many leaves subtending pseudobulbs rather than one or two as in the great majority of
Oncidiinae (Williams et al., 2001a). Previous authors had
used other floral traits (e.g. a trilobed lip in which the apical
lobe was smaller than the side lobes and often reflexed) in
circumscribing Cyrtochilum (Kraenzlin, 1922), but this also
did not produce a natural group. For example, it included
two species of the mule-ear group, Trichocentrum:
T. flavovirens (L.O.Williams) M.W.Chase & N.H.Williams
and T. microchilum (Bateman ex Lindl.) M.W.Chase &
N.H.Williams. When recircumscribing Trichocentrum, lower
chromosome numbers (2n ¼ 42 or less rather than 2n ¼ 56)
and reduced pseudobulbs with succulent leaves were emphasized (Williams et al., 2001b). A parallel to this situation is
to be found in Moraea (Iridaceae), in which Goldblatt
(1998) had to downplay floral traits in circumscribing
genera. In many groups of plants, pollination syndromes confound efforts to create a taxonomic scheme based on monophyletic groups.
We propose here to merge the principally Brazilian groups
of Oncidium with Gomesa, which we are certain will come
as surprise to many people familiar with Gomesa. Although
vegetatively compatible, flowers of Gomesa are completely
different in morphology (the lip parallels the column, as in
Chase et al. — Phylogenetics of Gomesa (Oncidiinae)
many species of Odontoglossum) and colour (mostly pale
green); Dressler (1981) reported that Gomesa is pollinated
by bees, but did not specify which sort. Gomesa has a synsepal, the leaf character (a glaucous surface), outwardly pointing
inflorescence bracts and flexed pedicels, and in spite of general
appearances it is fairly easy to diagnose Gomesa as a member
of this expanded genus based on these characters.
Gomesa had previously been considered to be closely
related to Oncidium (Pabst and Dungs, 1977), but of course
saying this does not help much since the latter is polymorphic
and polyphyletic. Dressler (1981) considered that Gomesa
might be congeneric with Ada Lindl., Brachtia Rchb.f. and
Mesospinidium Rchb.f., presumably because of the similar
lip/column relationships of these taxa. A relationship to
Binotia Rolfe, Rodrigueziella and Rodrigueziopsis is easy to
imagine because of their floral similarity to Gomesa, although
vegetatively all three are distinctive due to the relatively
elongate rhizome between growths and their reduced size.
Oncidium brunleesianum Rchb.f. (syn Baptistonia echinata)
is a particularly unusual member of Oncidium section
Waluewa; it has a lip that projects forward with the broad
side lobes enveloping the column, which are unusual traits
for a member of Oncidium. This trait led Szlachetko (1995)
to consider it to be a member of his subtribe Trichopiliinae
and not at all a close relative of either Gomesa or Oncidium.
Carriella colorata (Königer & J.G.Weinm.bis) V.P.Castro &
K.G.Lacerda, although described in Oncidium (Königer and
Weinmann, 2003), was segregated from Oncidium because it
is similar to Baptistonia, but it differs in floral traits as well,
the justification given for not including it in an expanded
concept of Baptistonia (Castro and Lacerda, 2005). In terms
of habit, B. echinata and Carriella colorata are typical
members of O. section Waluewa, and recently Chiron (2008)
transferred the latter to Baptistonia.
Chiron and Castro Neto (2004) transferred O. sarcodes
(section Crispa) to Baptistonia; its floral morphology is ‘intermediate’ between O. sections Waluewa and Crispa, but the
present analysis shows that Chiron and Castro Neto were
correct; it is a member of O. section Waluewa. Garay and
Stacy (1974) considered O. venustum (as O. trulliferum
Lindl., a well-known later synonym) a member of O. section
Rostrata because it has the typical beaked column of this
section, but this structure is a part of some oil-bee syndromes
and also occurs in otherwise unrelated groups of orchids with
other pollination syndromes (e.g. Phalaenopsis Blume, tribe
Vandeae). The present results show that O. venustum is also
embedded in the Gomesa clade, perhaps sister to Baptistonia
s.l. with high bootstrap support (Fig. 2). Chiron (2008) also
has recently transferred this species to Baptistonia.
Ornithophora radicans (Rchb.f.) Garay & Pabst was long
been considered problematic and perhaps to have a relationship
to Sigmatostalix Rchb.f. (Reichenbach originally placed it in
that genus). Production of oil and pollination by Centris bees
is accompanied by reduction in size of both flowers (which
makes sense given the small sizes of the bees) and plants, as
well as a long, beak-like column apex, which curves out
over the lip callus. Why this syndrome should involve
reduced vegetative stature is unclear, but G. radicans is a
good example of this (the bees are small, so floral reduction
makes sense). Most species of Sigmatostalix (now included
393
in Oncidium s.s.; Chase et al., 2008) are similarly small. A
relationship to the Brazilian sections of Oncidium was never
envisioned for this species; it was always viewed as either a
member of Sigmatostalix or the sole member of
Ornithophora. There are a number of similarities in the beaklike column of this species to those of Sigmatostalix and
Ornithocephalus, which share this type of the oil-bee syndrome. In 2003, Castro Neto and Chiron described a new
species in Oncidium section Rostrata, O. itapetingense
V.P.Castro & Chiron, which Baptista (in Docha Neto et al.,
2006) transferred to Carenidium. The floral morphology of
this species, with a beaked rostellum, is highly reminiscent
of G. radicans, and if material of this species becomes available we predict that it will fall as sister to G. radicans.
We do not propose a sectional classification of Gomesa here
because we believe that this serves little purpose in groups in
which parallelism is so rife; in practical terms this means that
neat boxes upon which such classifications have been typically
founded do not exist. Some of the sections of Garay and Stacy
(1974) do hold up reasonably well. For example, O. section
Waluewa has all of the species included there by Garay and
Stacy, but Baptistonia echinata, Carriella colorata,
O. sarcodes and O. venustum also belong here. However,
other sections like O. section Concoloria are grossly polyphyletic. Characters for O. section Concoloria are a simple lip
with a callus composed of a series or parallel keels and no
side lobes, and some of the species included here by Garay
and Stacy (1974) are members of Miltonia or Oncidium s.s.
Of the ten species Garay and Stacy included here, only
O. dasytyle Rchb.f., O. concolor Hook. and O. gracile Lindl.
fall in the Gomesa clade; the first two form a sister pair
embedded among members of O. section Crispa, whereas
the last is related to O. section Barbata (Fig. 3). To a large
extent, knowing something about phylogenetic relationships
makes natural subgeneric categories either extremely difficult
to create (as well as for which to write keys) or it renders
them artificial due to abandoning monophyly as the primary
guiding principle. Looking at the patterns of relationships in
Figs. 2 and 3, one can see that there are well-supported subclades within Gomesa s.l., but it is not possible to identify
clear sets of characters that could be used to serve as the
basis for constructing a workable classification within the
clade. Thus, we abandon the sections of Garay and Stacy
(1974) as unworkable and prefer not to set up such a system
ourselves. Szlachetko and colleagues transferred sections of
Oncidium sensu Garay and Stacy (1974) to segregate genera:
in the case of Brazilian groups these were O. section Crispa
to Anettea Szlach. & Mytnik, O. section Concoloria to
Concocidium Romowicz & Szlach. and O. section
Rhinocerotes to Rhinocerotidium Szlach. (Romowicz and
Szlachetko, 2006; Szlachetko, 2006; Szlachetko and
Mytnik-Ejsmont, 2006). Also in 2006, Campacci (in Docha
Neto et al., 2006) established the genus Brasilidium for the
species of section Crispa, but he included a different set of
species in his genus than Szlachetko and Mytnik-Ejsmont
(2006) included in Anettea (both cited the type species as
Oncidium crispum, so they are taxonomic synonyms in spite
of differing species composition). For example, Szlachetko
and Mytnik-Ejsmont (2006) included O. sarcodes in
Anettea, but Chiron and Castro Neto (2004) had transferred
394
Chase et al. — Phylogenetics of Gomesa (Oncidiinae)
this species to Baptistonia; Campacci did not include
O. sarcodes in Brasilidium in parallel with the treatment by
Chiron and Castro Neto (2004). Similarly, Baptista described
Carenidium based on the same type species as Romowicz
and Szlachetko (2006) had used for Concocidium, the type
of Oncidium section Concoloria (O. concolor), but they did
not circumscribe the species of these genera in the same
way; Romowicz and Szlachetko (2006) included there as
well species such as O. hyphaematicum Rchb.f., which is a
member of Oncidium s.s. Baptista at least excluded the
non-Brazilian species from Carenidium, but he included in
his concept two species, O. hookeri Rolfe and O. raniferum
Lindl. (O. section Raniferum sensu Garay and Stacy), that
are unrelated to the rest of Carenidium (Figs 2 and 3). This
problem was rectified by Chiron and Castro Neto (2006),
who segregated this group into Menezesiella. The species of
Menezesiella are indeed not related to those in Carenidium,
but instead they are embedded in Coppensia (Fig. 3).
Docha Neto et al. (2006) described several other new genera
to accommodate these mostly Brazilian groups, many of which
belong to the Gomesa clade, but these new genera are not
monophyletic, even though they stated that phylogeny should
be the basis of taxonomic practice. For example, in
Brasilidium, Campacci did not include O. concolor or
O. dasytyle, even though both are members of this clade
in the present analyses; instead Baptista placed them in
Carenidium. Campacci transferred all names he made in
Ampliglossum to Coppensia when he ( probably) mistakenly
thought that O. varicosum was related to O. bicolor. In the
present results, O. section Synsepala is not monophyletic,
and given the relationships shown in Figs 2 and 3,
Ampliglossum could still apply to a group of species related
to O. varicosum because they are not related to the group in
which we presume O. bicolor would fall (the clade containing
O. warmingii, in which the rest of the species of O. section
Synsepala fall). Oncidium varicosum, O. welteri Pabst and
O. insigne (Rolfe) Christenson would then be the members
of Ampliglossum, which are well supported as related to
O. macronyx Rchb.f., for which Baptista (in Docha Neto
et al., 2006) described Rhinocidium (Figs 2 and 3) and
Szlachetko (2006) later described Rhinocerotidium. The potential for confusion caused by differing generic concepts of these
various authors boggles even the minds of people who are
reasonably familiar with these taxa.
However, the story of confusion does not end here. Soon
after Baptista (in Docha Neto et al., 2006) described a new
genus, Alatiglossum Baptista, for the former members of O.
section Barbata, Castro Neto and Martins Catharino (2006)
desribed two other genera, Kleberiella V.P.Castro & Cath.
and Neoruschia Cath. & V.P.Castro, based on O. uniflorum
Booth ex Lindl. and O. cogniauxianum Schltr., respectively,
which had been included in Alatiglossum by Baptista. Also
in 2006, Chiron and Castro Neto described Menezesiella
Chiron & V.P.Castro for three of the species, O. hookeri,
O. loefgrenii Cogn. and O. raniferum, that Baptista had
included in Carenidium. Chiron and Castro Neto were
correct that these species are not related to those of O.
section Concoloria, and if we are to use the segregate
genera, then use of this name would be appropriate. Finally
(we hope) in 2008, Castro Neto and colleagues (including
Chiron) transferred another three species to Menezesiella,
even though they must certainly have been aware of these at
the time they described the genus (Castro Neto et al., 2008).
One of these newly transferred species was M. calimaniorum
(Guiard) V.P.Castro & G.F.Carr, which was the type species
for Castroa Guiard, published in 2006 with a photograph of
the species in the same journal in which Chiron (who is also
the chief editor) and Castro described Menezesiella (Guiard,
2006); from the photograph it is clear that Castroa calimaniora
is a member of Menezesiella. Some workers might prefer to
continue the process started by Chiron and Castro Neto
(2004, 2005a, b) and Docha Neto et al. (2006) in which successively new sets of genera would be established for the
Brazilian members of Oncidium, but once we publish our
results it seems certain that someone will decide to make
further changes to those that have already been published
and another new wave of synonyms will appear. From a
simple inspection of the results presented here (Figs 2
and 3), to produce a reasonable (monophyletic) system of
classification at least 15 genera must be recognized (some
not yet described; e.g. a new genus would be needed for
Oncidium gracile). If such fine splitting at the generic level
were to be extended to the whole of Oncidiinae, then there
would be double the number of genera to be recognized,
from 70 in Pridgeon et al. (2009) to well over 120. We
prefer instead to recognize larger and inevitably more heterogeneous generic limits rather than narrower but more homogeneous genera because this ultimately makes the
classification easier for most people to use; only experts are
able to tell apart the narrowly circumscribed taxa in the
Gomesa clade. It is telling that the Brazilians who claimed
to know these taxa well did not manage to circumscribe monophyletic genera and have published successive transfers of the
same species into new genera. Furthermore, Szlachetko and
colleagues fared no better with their reliance on column morphology in establishing monophyletic taxa. In effect, all these
workers have relied upon characters that are highly integrated
into pollination syndromes; this reliance prevented them from
understanding relationships and erecting natural taxa.
In previous classifications, there were two other species of
Oncidium that are known to occur in Brazil. Oncidium phymatochilum Lindl. is a vegetatively anomalous species, but it has
been shown by Williams et al. (2001b) to be sister to the
species of Miltonia, into which these authors transferred it.
Morphologically, this species is no more similar to Miltonia
than it is to Oncidium, but Williams et al. (2001b) stated
that monotypic genera are a redundancy in classification and
therefore decided to lump it with its sister taxon Miltonia.
Later, Christenson (2005) transferred it into its own genus,
Phymatochilum Christenson; in any case, it is no longer a
member of Oncidium. The other species, Oncidium orthostates
Ridl., occurs from the tepuis of the Guyana Highlands in
Venezuela (Amazonas and Bolivar) into Brazil (Amazonas,
Goiás, Rondônia, Roraima and Tocantins). This is a peculiar
distribution for a member of Oncidium or Gomesa; there are
no other members of these two genera in that region. It is
also a peculiar species in Oncidium or Gomesa due to
absence of a tabula infrastigmatica, although it otherwise
looks enough like section Synsepala for Campacci (in Docha
Neto et al., 2006) to transfer it into Ampliglossum and later
Chase et al. — Phylogenetics of Gomesa (Oncidiinae)
into Coppensia. In the present analyses, this species falls
neither with Oncidium nor Gomesa, but rather in an isolated
position between these two major clades (Fig. 3). Florally, it
is similar to Zelenkoa onusta (Lindl.) M.W.Chase &
N.H.Willaims, but it differs in habit and does not fall with
that species in any of the present analyses. A new genus for
it is described below. With the removal of this species from
Oncidium, O. baueri becomes the only member of Oncidium
in Brazil.
TA XO NO MIC T REAT MENT
Gomesa R.Br., Bot. Mag. t. 1748. 1815. Type species: Gomesa
recurva R.Br.
Synonyms:
Coppensia Dumort., Nouv. Mém. Acad. Roy. Sci. Bruxelles
9: 10. 1835. Type species: Coppensia bifolia (Sims) Dumort.
(basionym: Oncidium bifolium Sims).
Baptistonia Barb.Rodr., Gen. Sp. Orchid. 1: 95. 1877. Type
species: Baptistonia echinata Barb.Rodr.
Theodorea Barb.Rodr. (non Cass.), Gen. Sp. Orchid. 1: 144.
1877. Type species: Theodorea gomezoides Barb.Rodr.; this is
a later homonym of Theodorea Cass., a genus of Asteraceae.
Ornithophora Barb.Rodr., Gen. Sp. Orchid. 2: 225. 1882.
Type species: Ornithophora quadricolor Barb.Rodr.
(¼ Ornithophora radicans (Rchb.f.) Garay & Pabst).
Waluewa Regel, Trudy Imp. S.-Peterburgsk. Bot. Sada 11:
309. 1890. Type species: Waluewa pulchella Regel.
Rodrigueziella Kuntze, Rev. Gen. 649. 1891. Type species:
Rodrigueziella gomezoides (Barb.Rodr.) Kuntze (basionym:
Theodorea gomezoides Barb.Rodr.).
Binotia Rolfe, Orchid Rev. 13: 296. 1905. Type species:
Binotia brasiliensis Rolfe.
Rodrigueziopsis Schltr., Repert. Spec. Nov. Regni Veg. 16:
427. 1920. Type species: Rodrigueziopsis eleutherosepala
(Barb.Rodr.) Schltr.
Hellerorchis A.D.Hawkes, Orchid J. 3: 275. 1959. Type
species: Hellerorchis gomezoides (Barb.Rodr.) A.D.Hawkes
(basionym: Rodrigueziella gomezoides Barb.Rodr.).
Carria V.P.Castro & K.G.Lacerda (non Gardn.), Orchids 74:
694. 2005. Type species: Carria colorata (Königer &
J.G.Weinm.bis) V.P.Castro & K.G.Lacerda (basionym:
Oncidium coloratum Königer & J.G.Weinm.bis). Carria
Castro & Lacerda is a later homonym of Carria Gardn., a
genus in Ternstroemiaceae.
Carriella V.P.Castro & K.G.Lacerda, Icon. Orchid. Brasil.
2, t. 123. 2006. Type species: Carriella colorata (Königer &
J.G.Weinm.bis) V.P.Castro & K.G.Lacerda (basionym:
Oncidium coloratum Königer & J.G.Weinm.bis).
Alatiglossum D.H.Baptista, Colet. Orq. Bras. 3: 87. 2006.
Type species: Alatiglossum barbatum (Lindl.) D.H.Baptista
(basionym: Oncidium barbatum Lindl.).
Ampliglossum Campacci, Colet. Orq. Bras. 3: 83. 2006.
Type species: Ampliglossum varicosum Campacci (basionym:
Oncidium varicosum Lindl. & Paxton).
Anettea Szlach. & Mytnik, Pol. J. Bot. 51: 49. 2006. Type
species: Anettea crispa (Lodd.) Szlach. & Mytnik (basionym:
Oncidium crispum Lodd.).
395
Brasilidium Campacci, Colet. Orq. Bras. 3: 78. 2006. Type
species: Brasilidium crispum Campacci (basionym: Oncidium
crispum Lindl.).
Carenidium D.H.Baptista, Colet. Orq. Bras. 3: 90. 2006.
Type species: Carenidium concolor (Hook.) D.H.Baptista
(basionym: Oncidium concolor Hook.).
Castroa Guiard, Richardiana 6: 162. 2006. Type species:
Castroa calimaniana Guiard.
Concocidium Romowicz & Szlach., Pol. Bot. J. 51: 44.
2006. Type species: Concocidium concolor (Hook.)
Romowicz & Szlach. (basionym: Oncidium concolor Hook.).
Kleberiella V.P.Castro & Catharino, Richardiana 6: 158.
2006. Type species: Kleberiella uniflora (Booth ex Lindl.)
V.P.Castro & Catharino (basionym Oncidium uniflorum
Booth ex Lindl.).
Menezesiella Chiron & V.P.Castro, Richardiana 6: 103.
2006. Type species: Menezesiella ranifera (Lindl.) Chiron &
V.P.Castro (basionym: Oncidium raniferum Lindl.).
Neoruschia Catharino & V.P.Castro, Richardiana 6: 58.
2006. Type species: Neoruschia cogniauxiana (Schltr.)
Catharino & V.P.Castro (basionym: Oncidium cogniauxianum
Schltr.).
Rhinocidium D.H.Baptista, Colet. Orq. Bras. 3: 93. 2006.
Type species: Rhinocidium longicornu (Mutel) D.H.Baptista
(basionym: Oncidium longicornu Mutel).
Rhinocerotidium Szlach., Pol. Bot. J. 51: 40. 2006. Type
species: Rhinocerotidium longicornu (Mutel) Szlach. (basionym: Oncidium longicornu Mutel).
Gomesa 3 amicta (Lindl.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium amictum Lindl., Bot.
Reg. t. 66. 1847. (G. sarcodes G. lietzei).
Gomesa 3 colnagoi (Pabst) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium colnagoi Pabst, Bradea
2: 4. 1976. (G. forbesii G. zappii).
Gomesa 3 lita (Rchb.f.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium litum Rchb.f., Gard.
Chron., n.s. 20: 3328. 1883.
Gomesa 3 regentii (V.P.Castro and Chiron) M.W.Chase &
N.H.Williams, comb. nov.; basionym: Baptisonia regentii
V.P.Castro & Chiron, Richardiana 5: 187. 2005.
Gomesa 3 scullyi (Pabst & Mello) M.W.Chase &
N.H.Williams, comb. nov.; basionym: Oncidium scullyi
Pabst & Mello, Bradea 2: 187(-188), fig. D. 1977.
(G. curta 3 G. gravesiana).
Gomesa 3 wheatleyana (W.H.Gower) M.W.Chase &
N.H.Williams, comb. nov.; basionym: Oncidium wheatleyanum W.H.Gower, The Garden, 154: 227. 1893.
(G. imperatoris-maximimiliana G. dasytyle).
Gomesa adamantina (Marçal & Cath.) M.W.Chase &
N.H.Williams, comb. nov.; basionym: Oncidium adamantinum Marçal & Cath., Richardiana 6: 119. 2006.
Gomesa albinoi (Schltr.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium albinoi Schltr., Repert.
Spec. Nov. Regni Veg. 23: 63. 1926.
Gomesa barbaceniae (Lindl.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium barbaceniae Lindl., Fol.
Orch. Oncid. 6: 32. 1855.
Gomesa barbata (Lindl.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium barbatum Lindl., Coll.
Bot. t. 27. 1821.
396
Chase et al. — Phylogenetics of Gomesa (Oncidiinae)
Gomesa batemanniana (Parm. ex Knowles & Westc.)
M.W.Chase & N.H.Williams, comb. nov.; basionym:
Oncidium batemannianum Parm. ex Knowles & Westc., Fl.
Cab. 3: 183. 1840.
Gomesa bicolor (Lindl.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium bicolor Lindl., Bot. Reg.
66. 1843.
Gomesa bifolia (Sims) M.W.Chase & N.H.Williams, comb.
nov.; basionym: Oncidium bifolium Sims, Bot. Mag. 36:
t. 1491. 1812.
Gomesa blanchetii (Rchb.f.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium blancheti Rchb.f., Linnaea
22: 845. 1850.
Gomesa bohnkiana (V.P.Castro & G.F.Carr) M.W.Chase &
N.H.Williams, comb. nov.; basionym: Oncidium bohnkianum
V.P.Castro & G.F.Carr, Orchid Digest 70: 88. 2006.
Gomesa brasiliensis (Rolfe) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Binotia brasiliensis Rolfe, Orchid
Rev. 13: 296. 1905.
Gomesa brieniana (Rchb.f.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium brienianum Rchb.f. Gard.
Chron. nov. ser. 15: 40. 1881.
Gomesa brunnipetala (Barb.Rodr.) M.W.Chase &
N.H.Williams,
comb.
nov.;
basionym:
Oncidium
brunnipetalum Barb.Rodr., Gen. Sp. Orchid. 2: 190. 1881.
Gomesa caldensis (Rchb.f.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium caldense Rchb.f., Linnaea,
22: 846. 1849.
Gomesa
calimaniana
(Guiard)
M.W.Chase
&
N.H.Williams, comb. nov.; basionym: Castroa calimaniana
Guiard, Richardiana 6: 162. 2006.
Gomesa chapadensis (V.P.Castro & Campacci) M.W.Chase
& N.H.Williams, comb. nov.; basionym: Oncidium
chapadense V.P.Castro & Campacci, Orquidário 6: 150. 1992.
Gomesa chrysoptera (Lindl.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium macropetalum var. chrysopterum Lindl., Fol. Orch. Oncid. 16. 1855.
Gomesa chrysopterantha (Lückel) M.W.Chase &
N.H.Williams,
comb.
nov.;
basionym:
Oncidium
chrysopteranthum Lückel, Orchidee (Hamburg) 49: 43. 1998.
Gomesa
chrysorhapis
(Rchb.f.)
M.W.Chase
&
N.H.Williams, comb. nov.; basionym: Oncidium chrysorhapis
Rchb.f. Gard. Chron. ser. 3, 3: 72. 1888. Probably a synonym
of G. cornigera.
Gomesa chrysothyrsus (Rchb.f. ex Warn.) M.W.Chase &
N.H.Williams, comb. nov.; basionym: Oncidium chrysothyrsus Rchb.f. ex Warn., Sel. Orch. Ser. II. t. 5. 1864.
Gomesa ciliata (Lindl.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium ciliatum Lindl., Gen. Sp.
Orch. 200. 1833.
Gomesa
cogniauxiana
(Schltr.)
M.W.Chase
&
N.H.Williams,
comb.
nov.;
basionym:
Oncidium
cogniauxianum Schltr., Repert. Spec. Nov. Regni Veg. Beih.
9: 175. 1921.
Gomesa colorata (Königer & J.G.Weinm.) M.W.Chase &
N.H.Williams, comb. nov.; basionym: Oncidium coloratum
Königer & J.G.Weinm.bis.
Gomesa concolor (Hook.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium concolor Hook., Bot.
Mag. t. 3752. 1839.
Gomesa cornigera (Lindl.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium cornigerum Lindl.,
Edwards’s Bot. Reg. 18: t. 1542. 1832.
Gomesa croesus (Rchb.f.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium croesus Rchb.f., Hamb.
Garten-Blumenzeitung 13: 314. 1857.
Gomesa cruciata (Rchb.f.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium cruciatum Rchb.f., Gard.
Chron. 1: 138. 1878.
Gomesa cuneata (Scheidw.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium cuneatum Scheidw., Allg.
Gartenzeitung 10: 309. 1842.
Gomesa curta (Lindl.) M.W.Chase & N.H.Williams, comb.
nov.; basionym: Oncidium curtum Lindl., Edwards’s Bot. Reg.
33: t. 68. 1847.
Gomesa damacenoi (Chiron & V.P.Castro) M.W.Chase &
N.H.Williams, comb. nov.; basionym: Baptisonia damacenoi
Chiron & V.P.Castro, Richardiana 4: 124. 2004.
Gomesa dasytyle (Rchb.f.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium dasytyle Rchb.f., Gard.
Chron. 253. 1873.
Gomesa discifera (Lindl.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium disciferum Lindl., Fol.
Orch. Oncid. 24. 1855.
Gomesa doeringii (Hoehne) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Theodorea doeringii Hoehne, Arq.
Bot. Estado São Paulo, n.s., f.m., 1: 86. 1942.
Gomesa doniana (Batem. ex W.Baxt.) M.W.Chase &
N.H.Williams, comb. nov.; basionym: Oncidium donianum
Batem. ex W.Baxt., J.C. Loudon Suppl. Hort. Brit. 3: 598.
1850.
Gomesa
echinata
(Barb.Rodr.)
M.W.Chase
&
N.H.Williams, comb. nov.; basionym: Baptistonia echinata
Barb.Rodr., Gen. Sp. Orchid. 1: 95. 1877.
Gomesa edmundoi (Pabst) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium edmundoi Pabst, Bradea 1:
172, tab. 1, fig. B. 1972.
Gomesa eleutherosepala (Barb.Rodr.) M.W.Chase &
N.H.Williams, comb. nov.; basionym: Rodriguezia
eleutherosepala Barb.Rodr., Gen. Spec. Orchid. 2: 240. 1881.
Gomesa emilii (Schltr.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium emilii Schltr., Repert.
Spec. Nov. Regni Veg. 16: 449. 1920.
Gomesa enderiana (Hort. ex Gard. Chron.) M.W.Chase &
N.H.Williams, comb. nov.; basionym: Oncidium enderianum
Hort. ex Gard. Chron. 2: 75. 1892.
Gomesa eurycline (Rchb.f.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium eurycline Rchb.f., Gard.
Chron. 2: 812. 1883.
Gomesa flexuosa (Sims) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium flexuosum Sims, Bot.
Mag. t. 2203. 1821.
Gomesa forbesii (Hook.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium forbesii Hook., Bot. Mag.
65: t. 3705. 1839.
Gomesa fuscans (Rchb.f.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium fuscans Rchb.f., Otia Bot.
Hamb. 86. 1881.
Gomesa
fuscopetala
(Hoehne)
M.W.Chase
&
N.H.Williams,
comb.
nov.;
basionym:
Oncidium
Chase et al. — Phylogenetics of Gomesa (Oncidiinae)
macropetalum Lindl. var. fuscopetalum Hoehne, Relat.
Commiss. Linhas. Telegr. Estrateg. Matto Grosso Amazonas
5: 61, pl. 56, f. 2. 1910.
Gomesa gardneri (Lindl.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium gardneri Lindl., in Hook.,
Lond. J. Bot. 2: 662. 1843.
Gomesa gilva (Vell.) M.W.Chase & N.H.Williams, comb.
nov.; basionym: Epidendrum gilvum Vell., Fl. Flum.
lx. t. 33. 1831.
Gomesa gracilis (Lindl.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium gracile Lindl., Edwards’s
Bot. Reg. 23: t. 1920. 1837.
Gomesa gracillima (Schltr.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium gracillimum Cogn., in
Mart. Fl. Bras. 3(6): 401. 1906.
Gomesa gravesiana (Rolfe) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium gravesianum Rolfe, Gard.
Chron. ser. 3, 11: 650. 1892.
Gomesa gutfreundiana (Chiron & V.P.Castro) M.W.Chase &
N.H.Williams,
comb.
nov.;
basionym:
Oncidium
gutfreundianum Chiron & V.P.Castro, Richardiana 3: 122. 2003.
Gomesa hookeri (Rolfe) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium hookeri Rolfe, Gard.
Chron. ser. 3, 2: 520. 1941.
Gomesa hydrophila (Barb.Rodr.) M.W.Chase &
N.H.Williams, comb. nov.; basionym: Oncidium hydrophilum
Barb.Rodr., Gen. Sp. Orchid. 1: 92. 1877.
Gomesa insignis (Rolfe) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium varicosum Lindl. var.
insigne (Rolfe), Orchid Rev. 6: 27. 1898.
Gomesa imperatoris-maximiliani (Rchb.f.) M.W.Chase &
N.H.Williams, comb. nov.; basionym: Oncidium imperatorismaxiliani Rchb.f., in H.R.vanFernseeWawra, Bot. Ergebn.: 154.
1866. Synonym: Oncidium crispum Lodd. Gen. Sp. Orch. Pl.
197. 1833. Note: the epithet crispa is already occupied in
Gomesa, so we have used a later name for this species in Gomesa.
Gomesa isoptera (Lindl.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium isopterum Lindl.,
Edwards’s Bot. Reg. 23: t. 1920. 1837.
Gomesa itapetingensis (V.P.Castro & Chiron) M.W.Chase
& N.H.Williams, comb. nov.; basionym: Oncidium
itapetingense V.P.Castro & Chiron, Richardiana 3: 25. 2003.
Gomesa jucunda (Rchb.f.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Mesospinidium jucundum Rchb.f.,
Gard. Chron. (n. s.) 6: 580. 1876.
Gomesa kautskyi (Pabst) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium kautskyi Pabst, Bradea
2(14): 90, t. 2, E. 1976.
Gomesa leinigii (Pabst) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium leinigii Pabst, Bradea
1(20): 182, t. 3, f. B. 1972.
Gomesa lietzei (Regel) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium lietzei Regel, Act. Hort.
Petrop. 7: 387. 1880.
Gomesa loefgrenii (Cogn.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium loefgrenii Cogn., in Mart.
Fl. Bras. 3, pt. 6: 381, pl. 90, fig. 1. 1905.
Gomesa longicornu (Mutel) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium longicornu Mutel, Mem.
Scarpe. 13. 1838.
397
Gomesa longipes (Lindl. & Paxt.) M.W.Chase &
N.H.Williams, comb. nov.; basionym: Oncidium longipes
Lindl. & Paxt., Fl. Gard. 1: 46. 1850.
Gomesa macronyx (Rchb.f.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium macronyx Rchb.f., Otia
Bot. Hamb. 95. 1881.
Gomesa macropetala (Lindl.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium macropetalum Lindl., Sert.
Orch. sub t. 48. 1841.
Gomesa majevskyi (Toscano & V.P.Castro) M.W.Chase &
N.H.Williams, comb. nov.; basionym: Oncidium majevskyi
Toscano & V.P.Castro, Bradea 3: 349. 1983.
Gomesa mandonii (Rchb.f.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium mandonii Rchb.f., Xenia
Orch. 3: 21. 1878.
Gomesa marshalliana (Rchb.f.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium marshallianum Rchb.f., Gard.
Chron. 1866: 682. 1866.
Gomesa martiana (Lindl.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium martianum Lindl.,
Edwards’s Bot. Reg. 23: t. 1920. 1837.
Gomesa
megaloptera
(Kraenzl.)
M.W.Chase
&
N.H.Williams, comb. nov.; basionym: Oncidium megalopterum Kraenzl., in Engler, Pflanzenr. 4, Fam. 50: 156. 1922.
Gomesa microphyta (Barb.Rodr.) M.W.Chase &
N.H.Williams, comb. nov.; basionym: Rodriguezia
microphyta Barb.Rodr., Rev. Engenh. 3: 144. 1881.
Gomesa
micropogon
(Rchb.f.)
M.W.Chase
&
N.H.Williams, comb. nov.; basionym: Oncidium micropogon
Rchb.f., in Bonplandia (Hannover) 2: 90. 1854.
Gomesa
montana
(Barb.Rodr.)
M.W.Chase
&
N.H.Williams, comb. nov.; basionym: Oncidium montanum
Barb.Rodr., Gen. Sp. Orch. Nov. 1: 93. 1877.
Gomesa neoparanaensis (Chiron & V.P.Castro) M.W.Chase
& N.H.Williams, comb. nov.; basionym: Menezesiella
neoparanaensis Chiron & V.P.Castro, Richardiana 8: 51.
2008.
Gomesa nitida (Barb.Rodr.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium nitidum Barb.Rodr., Gen.
Sp. Orch. Nov. 2: 193. 1882.
Gomesa ouricanensis (V.P.Castro & Campacci)
M.W.Chase & N.H.Williams, comb. nov.; basionym:
Oncidium ouricanense V.P.Castro & Campacci, Bol. CAOB
4: 17. 1992.
Gomesa pabstii (Campacci & C.Espejo) M.W.Chase &
N.H.Williams, comb. nov.; basionym: Oncidium pabstii
Campacci & C.Espejo, Orquideophilo 6: 36. 1998.
Gomesa
paranaensis
(Kraenzl.)
M.W.Chase
&
N.H.Williams, comb. nov.; basionym: Oncidium paranaense
Kraenzl., in Svensk. Vet. Akad. Handl. XLVI, 10: 84. 1911.
Gomesa paranapiacabensis (Hoehne) M.W.Chase &
N.H.Williams,
comb.
nov.;
basionym:
Oncidium
paranapiacabense Hoehne, Arq. Bot. Estado São Paulo, new
ser. 1: 21, tab. 14. 1938.
Gomesa pardoglossa (Rchb.f.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium pardoglossum Rchb.f., Gard.
Chron. 1: 516. 1886.
Gomesa pectoralis (Lindl.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium pectorale Lindl., Sert.
Orch. t. 39. 1840.
398
Chase et al. — Phylogenetics of Gomesa (Oncidiinae)
Gomesa petropolitana (Pabst) M. W. Chase and
N. H. Williams, comb. nov.; basionym: Rodrigueziella petropolitana Pabst, Bradea 22: 87. 1976.
Gomesa pirarensis (Rchb.f.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium pirarense Rchb.f., Linnaea
22: 846. 1850.
Gomesa praetexta (Rchb.f.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium praetextum Rchb.f., Gard.
Chron. 1873: 1206. 1873.
Gomesa psyche (Schltr.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium psyche Schltr., Repert.
Spec. Nov. Regni Veg. 17: 16. 1921.
Gomesa pubes (Lindl.) M.W.Chase & N.H.Williams, comb.
nov.; basionym: Oncidium pubes Lindl., Bot. Reg. t. 1007. 1826.
Gomesa pulchella (Regel) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Waluewa pulchella Regel, Trudy
Imp. S.-Peterburgsk. Bot. Sada 11: 309. 1890. Synonym:
Oncidium waluewa Schltr., Repert. Spec. Nov. Regni Veg.
15: 215. 1918. Note: in Oncidium, the epithet pulchella is
occupied, so Schlechter published a new name for this
species, but in Gomesa it must have its original epithet.
Gomesa radicans (Rchb.f.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Sigmatostalix radicans Rchb.f.,
Walp. Ann. 6: 859. 1849.
Gomesa ramosa (Lindl.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium ramosum Lindl.,
Edwards’s Bot. Reg. 23: t. 1920. 1837.
Gomesa ranifera (Lindl.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium raniferum Lindl., Bot.
Reg. sub t. 1920, t. 48. 1838.
Gomesa reducta (Kraenzl.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium reductum Kraenzl., Repert.
Spec. Nov. Regni Veg. 26: 344. 1929.
Gomesa reichertii (L.C.Menezes & V.P.Castro) M.W.Chase
& N.H.Williams, comb. nov.; basionym: Coppensia reichertii
L.C.Menezes & V.P.Castro, Richardiana 8: 21. 2008.
Gomesa remotiflora (Garay) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium remotiflorum Garay,
Taxon 19: 454. 1970.
Gomesa rhinoceros (Rchb.f.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium rhinoceros Rchb.f., Bot.
Zeit. 14: 514. 1856.
Gomesa
riograndensis
(Cogn.)
M.W.Chase
&
N.H.Williams, comb. nov.; basionym: Oncidium riograndense
Cogn., Fl. Bras. (Martius) 3, pt. 6: 446, pl. 89, fig. 2. 1906.
Gomesa riviereana (St.-Lég.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium riviereanum St.-Lég., Rev.
Hort. Belge Étrangère, 30: 144; 1904.
Gomesa salesopolitana (V.P.Castro & Chiron) M.W.Chase
& N.H.Williams, comb. nov.; basionym: Menezesiella salesopolitana V.P.Castro & Chiron, Richardiana 6: 200. 2006.
Gomesa sarcodes (Lindl.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium sarcodes Lindl., Journ.
Hort. Soc. 4: 266. 1849.
Gomesa sellowii (Cogn.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium sellowii Cogn., in Mart.
Fl. Bras. 3, pt. 6: 404. 1906.
Gomesa silvana (V.P.Castro & Campacci) M.W.Chase &
N.H.Williams, comb. nov.; basionym: Oncidium silvanum
V.P.Castro & Campacci, Orquidário 5: 22. 1991.
Gomesa sincorana (Campacci & Cath.) M.W.Chase &
N.H.Williams, comb. nov.; basionym: Coppensia sincorana
Campacci & Cath., Bol. CAOP 64: 124. 2006.
Gomesa spiloptera (Lindl.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium spilopterum Lindl.,
Edwards’s Bot. Reg. 30 Misc.: 75. 1844.
Gomesa trichodes (Lindl.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium trichodes Lindl., Fol.
Orch. Oncid. 6: 15. 1855.
Gomesa truncata (Pabst) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium truncatum Pabst, Orquidea
(Rio de Janeiro) 17: 45. 1955.
Gomesa uhlii (Chiron & V.P.Castro) M.W.Chase &
N.H.Williams, comb. nov.; basionym: Baptistonia uhlii
Chiron & V.P.Castro, Richardiana 6: 21. 2006.
Gomesa unicolor (Rolfe) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium unicolor Rolfe, Orchid
Rev. 1: 266. 1893.
Gomesa uniflora (Booth ex Lindl.) M.W.Chase &
N.H.Williams, comb. nov.; basionym: Oncidium uniflorum
Booth ex Lindl., Edwards’s Bot. Reg. 29: t. 43. 1843.
Gomesa varicosa (Lindl.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium varicosum Lindl.,
Edwards’s Bot. Reg. 23: t. 1920. 1837.
Gomesa velteniana (V.P.Castro & Chiron) M.W.Chase &
N.H.Williams, comb. nov.; basionym: Baptistonia velteniana
V.P.Castro & Chiron, Richardiana 5: 80. 2005.
Gomesa venusta (Drapiez) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium venustum Drapiez, Hort.
Belge 3: 28. 1836.
Gomesa viperina (Lindl.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium viperinum Lindl., Gen. Sp.
Orch. 197. 1833.
Gomesa warmingii (Rchb.f.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium warmingii Rchb.f., Otia Bot.
Hamb. 86. 1881.
Gomesa welteri (Pabst) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium welteri Pabst, Arch. Jard.
Bot. Rio de Janeiro 14: 25, tab. 7B. 1956.
Gomesa widgreni (Lindl.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium widgreni Lindl., Fol. Orch.
Oncid. 6: 17. 1855.
Gomesa williamsii (Schltr.) M.W.Chase & N.H.Williams,
comb. nov.; basionym: Oncidium williamsii Schltr., Repert.
Spec. Nov. Regni Veg. 10: 459. 1912.
Gomesa zappii (Pabst) M.W.Chase & N.H.Williams, comb.
nov.; basionym: Oncidium zappii Pabst, Bradea 2(22):
3. 1976.
Not transferred: Oncidium kraenzlinianum Cogn. because it
does not appear to be a member of this group, even though
Garay put it in O. section Synsepala. From its description, it
could be Caucaea radiata.
We describe below a new genus for the singular species,
Oncidium orthostates Ridl., which differs in floral traits from
all other genera of Oncidiinae. This species has a peculiar distribution in the Guyana Highlands of Venezuela, Guyana and
Brazil. The species is sister to clades of other genera and is not
resolved as sister to any other single taxon. It is most similar
florally to Zelenkoa onusta (Lindl.) M.W.Chase &
N.H.Williams., the single species of that genus, but it never
Chase et al. — Phylogenetics of Gomesa (Oncidiinae)
comes out exclusively with it. We name the new genus in
honour of Norris H. Williams, who has spent his botanical
career studying members of Oncidiinae and pollination
biology of neotropical orchids.
Nohawilliamsia M.W. Chase & Whitten, gen. nov.
Plantae terrestres vel lithophyticae, parvae, pseudobulbi lati
oblongi, 1 vel 2 bracteis foliiferis subtenti, folio apicali 1 vel
2. Folia crassa. Inflorescentia lateralis, racemosa, plerumque
non ramosa, floribus numerosis. Structura floris Oncidio
similis, sed tabula infrastigmatica carenti atque columna
brevi. Pollinia dua.
Small, perennial, caespitose herbs, terrestrial to lithophytic,
with pseudobulbs clustered on a short rhizome. Pseudobulbs
oblong to elliptical-oblong in outline, weakly ancipitous,
weakly ridged longitudinally, usually with 1 –2 terminal
leaves, composed of a single internode, lower portions
concealed by 3 – 4 sheathing bracts, the uppermost 1 – 2 with
a lamina. Leaves elliptic-lanceolate, coriaceous, glabrous,
conduplicate, margins entire, eventually deciduous.
Inflorescences produced laterally from the base of the pseudobulb, subtended by a sheathing bract, much longer than leaves,
racemose (rarely sparsely branched), many-flowered, in some
cases producing plantlets at nodes after flowering. Flowers
showy, resupinate, pedicellate ovary twisted, glabrous.
Sepals free, more or less equal in size to the petals, shortly
elliptic, dorsally carinate and shortly acuminate. Petals free,
same shape as sepals; lip broadly attached to column, trilobed
with the apical lobe much larger than the lateral lobes and apically cleft, with a basal trilobed callus. Column shorter than
dorsal sepal, swollen apically, with a pair of lateral wings on
the sides of the stigma; stigma round; anther terminal operculate, incumbent, one-celled; pollinarium with two, hard, waxy
pollinia with an obvious, abaxial suture, attached to the head
of an elongate stipe by irregularly shaped viscin (caudicles);
viscidium oval in outline. Capsules and seeds not seen.
Seedlings not seen.
There is at this time only a single species in this genus, and
we here transfer it formally to Nohawilliamsia.
Nohawilliamsia orthostates (Ridl.) M.W.Chase & Whitten,
comb. nov.; basionym: Oncidium orthostates Ridl., Timehri 5:
204. 1886.
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724– 732.
APPENDIX
Taxa, vouchers and GenBank accession numbers
Species
Authors
Comparettia falcata
Poepp. & Endl.
Cyrtochilum serratum
(Lindl.) Kraenzl.
Erycina hyalinobulbon
(Llave & Lex.)
N.H. Williams &
M.W. Chase
(Lindl.) M.W.Chase
& N.H.Williams
(Lindl.) M.W.Chase
& N.H.Williams
Hoffmanns.
Gomesa barbaceniae
Gomesa barbata
Gomesa chrysostoma
Gomesa ciliata
Gomesa cogniauxiana
Gomesa colorata
Gomesa concolor
Gomesa crispa
(Lindl.) M.W.Chase
& N.H.Williams
(Schltr.) M.W.Chase
& N.H.Williams
(Königer &
J.G.Weinm.bis)
M.W.Chase &
N.H.Williams
(Hook.) M.W.Chase
& N.H.Williams
(Lindl.) Klotzsch
ex Rchb.f.
Gomesa glaziovii
(Rchb.f.) M.W.Chase
& N.H.Williams
(Rchb.f.) M.W.Chase
& N.H.Williams
(Barb.Rodr.)
M.W.Chase &
N.H.Williams
(Sims) M.W.Chase &
N.H.Williams
(Hook.) M.W.Chase
& N.H.Williams
Cogn.
Gomesa gomezoides
(Barb.Rodr.) Pabst
Gomesa dasytyle
Gomesa echinata
Gomesa eleutherosepala
Gomesa flexuosa
Gomesa forbesii
Voucher
Herbarium/
number
GenBank
ITS
GenBank
matK
GenBank
30 ycf1
GenBank
50 ycf1
GenBank
trnH-psbA
FLAS
FJ565601
FJ565090
FJ563757
FJ563043
FJ564609
Whitten
2688
Whitten
3427;
Whitten
91289
Chase 83395
FLAS
AF432961
AF239494
FJ563260
FJ562567
FJ564123
K
AF350536
AF350615
EU490744
FJ562474
FJ564026
Faria 23
UEC
FJ565420
FJ564911
FJ563545
FJ562837
FJ564397
Semir sn
UEC
FJ565431
FJ564924
FJ563558
FJ562849
FJ564410
Faria et al.
s.n.
Chase O-137
UEC
100.117
K
FJ565408
FJ564899
FJ563533
FJ562825
FJ564385
FJ565217
FJ564730
FJ563205
FJ562514
FJ564066
UEC
103.073
Gerlach
03/2467
UEC
FJ565409
FJ564900
FJ563534
FJ562826
FJ564386
M
FJ565242
FJ564754
FJ563246
FLAS
FJ565323
FJ564816
FJ563406
FJ562704
FJ564261
FJ564107
Williams
N341
Faria &
Pansarin
1022
Chase O-210
UEC
FJ565415
FJ564906
FJ563540
FJ562832
FJ564392
K
AF350551
AF350630
FJ563220
FJ562529
FJ564080
Faria et al.
s.n.
Chase 83426
UEC
99.183
K
FJ565406
FJ564897
FJ563531
FJ562823
FJ564383
FJ565203
FJ564717
FJ563171
FJ562478
FJ564030
Chase O-98
K
AF350552
AF350631
FJ563189
FJ562497
FJ564049
Faria &
Ribeiro 1039
Faria et al
1034
Chase O-151
UEC
FJ565429
FJ564922
FJ563556
FJ562847
FJ564408
UEC
FJ565433
FJ564926
FJ563560
FJ562851
FJ564412
K
AF350553
AF350632
FJ563213
FJ562522
FJ564074
Continued
Chase et al. — Phylogenetics of Gomesa (Oncidiinae)
AP P E N D I X
Species
Gomesa gracilis
Gomesa handroi
Gomesa hookeri
Gomesa hydrophila
Gomesa
imperatorismaximiliani
Gomesa kautskyi
Gomesa lietzei
Gomesa longipes
Gomesa macronyx
Gomesa macropetala
Gomesa pirarensis
Gomesa planifolia
Gomesa praetexta
Gomesa pubes
Gomesa radicans
Gomesa ranifera
Gomesa recurva
Gomesa sarcodes
Gomesa sessilis
Gomesa spiloptera
Gomesa varicosa
Gomesa varicosa
Gomesa venusta
Gomesa viperina
Gomesa warmingii
Gomesa warmingii
Gomesa welteri
Gomesa widgrenii
Nohawilliamsia
orthostates
Oncidium altissimum
Oncidium durangense
GenBank
matK
GenBank
30 ycf1
GenBank
50 ycf1
UEC
FJ565411
FJ564902
FJ563536
FJ562828
FJ564388
UEC
UEC
FJ565427
FJ564928
FJ564920
FJ563562
FJ563554
FJ562853
FJ562845
FJ564414
FJ564406
UEC
FJ565419
FJ564910
FJ563544
FJ562836
FJ564396
Chase 84504
K
FJ565207
FJ564720
FJ563181
FJ562489
FJ564041
Faria 37
UEC
FJ565423
FJ564914
FJ563548
FJ562839
FJ564400
Whitten
3001
Pansarin
725
FLAS
FJ565625
FJ565117
FJ563786
FJ563071
FJ564638
UEC
FJ565417
FJ564908
FJ563542
FJ562834
FJ564394
Chase 85121
K
FJ565199
FJ564713
FJ563160
FJ562465
FJ564017
Faria et al.
s.n.
Faria et al.
s.n.
Chase 83424
Faria &
Ribeiro 1036
Chase 85119
UEC
98.005
UEC
100.123
K
UEC
FJ565424
FJ564915
FJ563549
FJ562840
FJ564401
FJ565418
FJ564909
FJ563543
FJ562835
FJ564395
AF350554
FJ565412
AF350633
FJ564903
FJ563159
FJ563537
FJ562464
FJ562829
FJ564016
FJ564389
K
FJ565190
FJ563836
FJ563139
FJ562444
FJ563995
Whitten
2988,
Whitten
99254
Chase 85122
FLAS
FJ565624
FJ565116
FJ563785
FJ563070
FJ564637
K
FJ565200
FJ564714
FJ563161
FJ562466
FJ564018
UEC
FJ565435
FJ564929
FJ563563
FJ562854
FJ564415
UEC
FJ565422
FJ564913
FJ563547
FJ562838
FJ564399
UEC
FJ565434
FJ564927
FJ563561
FJ562852
FJ564413
UEC
FJ565428
FJ564921
FJ563555
FJ562846
FJ564407
UEC
FJ565432
FJ564925
FJ563559
FJ562850
FJ564411
FLAS
FJ565668
FJ565161
FJ563829
FJ563113
FJ564682
FLAS
FJ565358
FJ564850
FJ563458
FJ562754
FJ564310
M
FJ565347
FJ564841
FJ563446
FJ562742
FJ564298
K
FJ565226
FJ564739
FJ563228
FJ562539
FJ564089
Costa 049/
2003
Faria et al
1015
Whitten
3559
Chase 8175
UEC
FJ565430
FJ564923
FJ563557
FJ562848
FJ564409
UEC
FJ565416
FJ564907
FJ563541
FJ562833
FJ564393
FLAS
FJ565658
FJ565150
FJ563818
FJ563103
FJ564671
K
FJ565399
FJ563950
FJ563521
FJ562816
FJ564373
Atwood 5602
Whitten
99246
FLAS
FLAS
FJ565295
AF350811
FJ563914
FJ564941
FJ563363
FJ563587
FJ562663
FJ562876
FJ564220
FJ564438
Voucher
(Lindl.) M.W.Chase
& N.H.Williams
(Hoehne) Pabst
(Rolfe) M.W.Chase
& N.H.Williams
(Barb.Rodr.)
M.W.Chase &
N.H.Williams
(Rchb.f.) M.W.Chase
& N.H.Williams
(Pabst) M.W.Chase
& N.H.Williams
(Regel) M.W.Chase
& N.H.Williams
(Lindl. & Paxt.)
M.W.Chase &
N.H.Williams
(Rchb.f.) M.W.Chase
& N.H.Williams
(Lindl.) M.W.Chase
& N.H.Williams
(Rchb.f.) M.W.Chase
& N.H.Williams
Klotzsch ex Rchb.f.
(Rchb.f.) M.W.Chase
& N.H.Williams
(Lindl.) M.W.Chase
& N.H.Williams
(Rchb.f.) M.W.Chase
& N.H.Williams
Faria et al
975
Koehler s.n.
Faria et al
1020
Singer et al
s.n.
(Lindl.) M.W.Chase
& N.H.Williams
Barb.Rodr.
(Lindl.) M.W.Chase
& N.H.Williams
(Lindl.) M.W.Chase
& N.H.Williams
(Lindl.) M.W.Chase
& N.H.Williams
(Lindl.) M.W.Chase
& N.H.Williams
(Lindl.) M.W.Chase
& N.H.Williams
(Rchb.f.) M.W.Chase
& N.H.Williams
(Rchb.f.) M.W.Chase
& N.H.Williams
(Pabst) M.W.Chase
& N.H.Williams
(Lindl.) M.W.Chase
& N.H.Williams
(Ridl.) M.W. Chase
& Whitten
(Jacq.) Sw.
Hagsater
Continued
GenBank
ITS
Authors
(Lindl.) M.W.Chase
& N.H.Williams
Lodd.
401
Faria et al
1042
Pansarin
315
Faria et al
116
Faria et al.
98/32
Faria et al
1043
Whitten
3611
Williams
N522 MSBG
1981–1050A
Gerlach 98/
2080
Chase 86211
Herbarium/
number
GenBank
trnH-psbA
Continued
402
Chase et al. — Phylogenetics of Gomesa (Oncidiinae)
AP P E N D I X
Species
Oncidium
ghiesbreghtianum
Oncidium hastatum
Oncidium maculatum
Oncidium oblongatum
Oncidium reichenbachii
Oncidium wydleri
Otoglossum chiriquense
Rodriguezia lanceolata
Tolumnia henekenii
Warmingia eugenii
Zelenkoa onusta
Authors
Voucher
Continued
Herbarium/
number
GenBank
ITS
GenBank
matK
GenBank
30 ycf1
GenBank
50 ycf1
GenBank
trnH-psbA
A. Rich. & Galeotti
Chase 86117
K
AF350563
AF350642
FJ563190
FJ562498
FJ564050
(Ruiz & Pavon)
Mansf.
(Lindl.) Lindl.
Lindl.
Whitten
3016
Atwood 5604
Williams
N220
Atwood 5605
Chase 86069
Chase 86242
FLAS
AF350812
FJ564787
FJ563350
FJ562652
FJ564209
FLAS
FLAS
AF350806
AF350820
FJ563917
FJ563912
FJ563366
FJ563358
FJ562666
FJ562659
FJ564223
FJ564216
FLAS
K
K
AF350805
AF350801
AF432977
FJ563916
FJ563849
AF433036
FJ563365
FJ563187
FJ563174
FJ562665
FJ562495
FJ562481
FJ564222
FJ564047
FJ564033
K
FLAS
AF350542
AF350535
AF350621
AF350614
FJ563162
FJ563275
FJ562467
FJ562582
FJ564019
FJ564137
K
K
FJ565196
AF350555
FJ563841
AF350634
FJ563154
FJ563178
FJ562459
FJ562485
FJ564011
FJ564037
Lindl.
Rchb.f.
(Rchb.f.) Garay &
Dunst.
Ruiz & Pav.
(R.H. Schomb. ex
Lindl.) Nir
Rchb.f.
(Lindl.) N.H.
Williams & M.W.
Chase
Chase 83002
Whitten
3017
Chase 84460
Chase 83170
norris williams