Silene shehbazii S. A. Ahmad (Caryophyllaceae), a new species from Kurdistan, Iraq, is described, and characters distinguishing it from its nearest relatives, S. odontopetala Fenzl and S. pseudonurensis Melzh., are discussed.

The Dimocarpus longan Lour. (Sapindaceae) species complex is reevaluated, and D. longan s.l. is divided into three species, of which two are divided into two varieties. Three new combinations, D. cinereus (Radlk.) Boonsuk & Chantar., D. cinereus var. echinatus (Leenh.) Boonsuk & Chantar., and D. scandens (Winit & Kerr) Boonsuk & Chantar., are here proposed. The name Euphoria pallens Pierre is lectotypified.

Disocactus salvadorensis Cerén, Menjívar & S. Arias is described and illustrated. This new Cactaceae species grows in the northwestern department of Santa Ana, in El Salvador. It is a member of subgenus Disocactus and is distinguished by its tubular and pendulous flowers with yellow or pink, less often white, tepals that are erect but recurved in the distal one third, and by its stamens in two distant whorls. Within Disocactus Lindl. subg. Disocactus, this new species is morphologically most similar to D. eichlamii (Weing.) Britton & Rose and D. quezaltecus (Standl. & Steyerm.) Kimnach. Distribution and ecological information about the new species are provided.

A new species of Arecaceae, Wettinia donosoensis De Gracia & Grayum, from the Atlantic slope of Panama, is described and illustrated. It is readily distinguished from all other species of Wettinia Poepp. by the combination of small size (3–5 m); leaves with few (usually six or seven per side) pinnae; unbranched, lax inflorescences; and very long petals (in pistillate flowers, 25–30 mm). It is endemic to a small region in Donoso District, Colón Province, and its conservation status is assessed as Endangered.

Some aspects concerning the typification of Platanus occidentalis L. (Platanaceae) are discussed. This name had been typified previously by Reveal in 2009 from a specimen kept at LINN. However, it is unclear whether this specimen is part of Linnaeus's original material so it cannot be considered a lectotype. A specimen conserved in the Linnean Herbarium Herb. Linn. No. 388.17 (S-LINN) is designated here as the lectotype of the name P. occidentalis.

A new fern species, Polystichum tiandengense H. He & Li Bing Zhang (Dryopteridaceae), is described and illustrated from a limestone cave in the Guangxi Zhuangzu Autonomous Region, South China. Polystichum tiandengense is most similar to P. cavernicola Li Bing Zhang & H. He in having oblong to square pinnae with undulate margins, but the new species is distinguished by its pinnae mostly adjacent to each other or imbricating, and mostly sterile (vs. distant from each other and mostly fertile in P. cavernicola). Polystichum tiandengense is considered to be Critically Endangered (CR), based on IUCN Red List criteria.

The new species Potentilla tuberculifera J. Z. Dong (Rosaceae) is described and illustrated from Guangshui, China. It differs from P. freyniana Bornm. in being an indeciduous herb with winter leaves 1.5 × 1.3 cm with a deeply red abaxial surface, and summer leaves green and 4–6.5 × 6–8.5 cm; in having long, red, procumbent stolons, bearing a short branch at each node whose terminal expands into a tubercle with adventitious roots; and in reproducing mostly asexually by tubercles, with matured achenes zero to three per fruit. This new species is considered to be endangered because of its narrow range and limited ability to reproduce.

We describe an interesting new Primula L. species, P. hubeiensis X. W. Li, which is similar to P. filchnerae R. Knuth, with leaves pinnately lobed and glandular hairs on the leaves and inflorescences. However, P. hubeiensis has more pinnae on the leaves (six to nine vs. three to four pairs) and smaller capsules (3–4 mm diam. vs. 10–16 mm diam.). The persistent calyx of P. filchnerae develops into the shape of a lantern when the fruits are mature, but the calyx of P. hubeiensis is elongated and split almost to the base during fruiting. Primula filchnerae has been placed in Primula sect. Auganthus (Link) Pax ex Balf. f. due to the character of its indument and deeply lobed leaves; P. hubeiensis might also belong in this section, but this needs further confirmation.

This paper provides a description of an extinct domesticated subspecies of erect knotweed (Polygonum erectum L.). Masses of erect knotweed achenes are often recovered from archaeological sites in eastern North America dating to ca. 3000–600 BP. Several paleoethnobotanical assemblages from the later part of this era (ca. 1000–600 BP) contain achenes that are outside the range of natural variation for erect knotweed. The most well preserved of these archaeological assemblages, a desiccated cache of achenes from the Whitney Bluff site, Arkansas (ca. 900 BP), is compared to four closely related species and subspecies of Polygonum L. The Whitney Bluff achenes are most similar to those of P. erectum, but differ from modern fruits of this species in three respects: (1) fruits are larger, (2) average pericarp thickness is reduced, and (3) fruit dimorphism is greatly reduced. These differences are typical of domestication syndrome in annual seed crops. The Whitney Bluff assemblage is described as the type specimen of a domesticated subspecies, P. erectum subsp. watsoniae N. G. Muell.

Recent studies have shown that the genus Acacia Mill. s.l. is polyphyletic, consisting of at least seven distinct groups of species. One of these groups, the proposed genus Parasenegalia Seigler & Ebinger, consists of seven species. We describe a new species, Parasenegalia lundellii Seigler & Ebinger, and make the following new combinations: Parasenegalia muricata (L.) Seigler & Ebinger, Parasenegalia rurrenabaqueana (Rusby) Seigler & Ebinger, Parasenegalia santosii (G. P. Lewis) Seigler & Ebinger, Parasenegalia skleroxyla (Tussac) Seigler & Ebinger, Parasenegalia visco (Lorentz ex Griseb.) Seigler & Ebinger, and Parasenegalia vogeliana (Steud.) Seigler & Ebinger. A second proposed genus, Pseudosenegalia Seigler & Ebinger, consists of two species: Pseudosenegalia feddeana (Harms) Seigler & Ebinger and Pseudosenegalia riograndensis (Atahuachi & L. Rico) Seigler & Ebinger. The species of Parasenegalia are widespread in the tropical areas of the Caribbean and scattered in Central and South America. Those of Pseudosenegalia are found in Bolivia. A series of morphological characteristics, as well as recent molecular data, separate these new genera from other members of Acacia subg. Aculeiferum Vassal. Although members of these two genera are distinct, previous taxonomic treatments have not dealt with them as separate units within Acacia subg. Aculeiferum. Lectotypes are designated for the following names: Acacia concinna Phil., Acacia polyphylla Clos, Acacia riparia Kunth var. angustifoliola Kuntze, Parasenegalia visco (Lorentz ex Griseb.) Seigler & Ebinger [≡ Acacia visco Lorentz ex Griseb.], and Pseudosenegalia feddeana (Harms) Seigler & Ebinger [≡ Acacia feddeana Harms].

Six species have been described for the genus Orinus Hitchc. (Poaceae). Our analyses of morphological and genetic variation at the population level indicate that the genus should be reduced to three species, one of which, O. intermedius X. Su & J. Quan Liu, we describe as new from the Qinghai-Tibet Plateau. We include a complete taxonomic revision of the genus, a key to distinguish the three species, and geographic distribution and habitat data for each species.

Recent botanical explorations in western tropical South America provide new documentation of Joosia H. Karst., which has clarified some species identities and discovered some new species. Eighteen species are recognized here, with J. umbellifera H. Karst. circumscribed more narrowly than in previous taxonomies and J. panamensis Dwyer and J. ulei Steyerm. separated from it. Two new nomenclatural combinations are made: J. loretensis (Standl.) C. M. Taylor is based on Rondeletia loretensis Standl., and J. sericea (Standl.) C. M. Taylor is based on Ladenbergia sericea Standl. and is an older name for J. multiflora L. Andersson. Three species are newly described here: J. capitata C. M. Taylor from northern Peru, with subcapitate inflorescences and dense hirtellous to hirsute pubescence; J. confusa C. M. Taylor from Ecuador and Peru, with dichasial axes and shallowly lobed calyx limbs; and J. frondosa C. M. Taylor from Colombia, with enlarged whitened bracts and calyx lobes. Joosia has its center of species diversity in montane Ecuador and Peru; it is now documented also from Bolivia, where J. sericea is found, and from Venezuela, but that material is inadequate for identification to species.

The identity, circumscription, and nomenclatural details of some species of “traditional” Palicourea Aubl. and one section are studied here. The species belong to both subgenera of Palicourea. Three species are re-circumscribed, two names are lectotypified, four new nomenclatural combinations are published, eight species of Palicourea subg. Montanae C. M. Taylor are newly described, and several names are newly synonymized. In Palicourea subg. Palicourea: the new combination Palicourea paulina (Standl.) C. M. Taylor is based on Psychotria paulina Standl. and is an older name for Palicourea plowmanii D. R. Simpson ex C. M. Taylor. The circumscription and morphological characterization of Palicourea sect. Corymbiferae (Müll. Arg.) C. M. Taylor are expanded, nine species are included, and Psychotria L. sect. Regina Müll. Arg. is synonymized here. The name Psychotria corymbifera Müll. Arg. is typified. Palicourea quadrifolia (Rudge) DC. subsp. leticiana C. M. Taylor is recognized as a species that takes the name Palicourea lucidula Standl. The new combination Palicourea regina (Müll. Arg.) C. M. Taylor is based on Psychotria regina Müll. Arg. The morphology of Palicourea virens (Poepp.) Standl. is evaluated, and Palicourea quinata Suess. is synonymized here. In Palicourea subg. Montanae: Palicourea albocaerulea C. M. Taylor is newly reported from Honduras. The new species Palicourea betancuriana C. M. Taylor of northwestern Colombia differs from Palicourea standleyana C. M. Taylor by its longer calyx limbs and purple corollas. The new combination Palicourea ceriantha (K. Schum.) C. M. Taylor is based on Rudgea ceriantha K. Schum. and is an older name for Palicourea clerodendroides C. M. Taylor. The new species Palicourea foreroi C. M. Taylor of western Andean Colombia differs from Palicourea pyramidalis Standl. by its longer pedicels and corollas. The new species Palicourea hondurensis C. M. Taylor of Honduras differs from Palicourea albocaerulea by its short calyx lobes and usually longer stipule lobes. The new species Palicourea kahirica C. M. Taylor of western Andean Colombia differs from Palicourea lehmannii (K. Schum. & K. Krause) Standl. by its shorter corollas without abaxial horns on the lobes. The new species Palicourea lozanoana C. M. Taylor of eastern Andean Colombia differs from Palicourea denslowiae J. H. Kirkbr. by its laminar stipules, shorter calyx limbs, and corollas without abaxial horns on the lobes. The new species Palicourea murciae C. M. Taylor of Andean Colombia differs from Palicourea weberbaueri K. Krause by its dense velutinous pubescence and shorter corollas. The new species Palicourea parrana C. M. Taylor of eastern Andean Colombia differs from Palicourea petiolaris Kunth by its longer corollas. The new combination Palicourea sanchezii (C. M. Taylor) C. M. Taylor is based on Psychotria sanchezii C. M. Taylor. The new species Palicourea sancti-ciprianii C. M. Taylor of western coastal Colombia and northwestern Ecuador differs from Palicourea vulcanalis Standl. ex C. M. Taylor by its stipules with shorter sheaths and its smaller inflorescences.