Pinus densata, universally considered a Tertiary hybrid species, was studied throughout its distribution range, together with all the related species that form the P. kesiya complex. The heterogeneously classified pine populations of this complex from the Tibetan region of the Brahmaputra catchment area are distinguished as a new subspecies, Pinus densata subsp. tibetica, characteristic of deep valley systems under 3000 m. In areas in N Yunnan and S Sichuan, where populations of P. densata and P. yunnanensis have been in recent contact, secondary introgressive hybridization was distinguished and a new hybrid, P. × naxiorum, is described. Biogeographic data for P. densata subsp. tibetica (including a distribution map for both subspecies) are given, along with data from a discovered eastern site of P. densata var. pygmaea. Akey that partially revises the key from Flora of China and summarizes the taxa of the P. kesiya complex and other similar taxa is given. A hypothesis of the phylogeography of P. densata is formulated based on the compilation of available data.

Aspectacular new species of Aldina Endl. (Fabaceae-Swartzieae-Aldininae) from the Guayana Highlands of Venezuela is described and illustrated. Aldina diplogyne resembles A. latifolia Spruce ex Benth. var. latifolia with its ovate, glabrous, nitid, generally coriaceous leaflets; the rather large, mature flower buds; and the showy flowers with a stout, exerted gynophore. However, it is distinguished from all other species of the genus by the much larger, showy flowers, which have a gynoecium of 2–4 functional carpels with the ovaries on longexerted, robust gynophores.

Roraimaea (Gentianaceae: Helieae) is a new angiosperm genus from northern Brazil and southern Venezuela. This genus differs prominently from other taxa of the Gentianaceae tribe Helieae by its long-tubular, orange to red corollas, and deeply cleft styles with filiform lobes. Traditionally, pollen characters have been used as important traits to distinguish genera in the tribe Helieae. The pollen of Roraimaea is shed as tetrads and has an evenly thick, coarsely reticulate exine, which is similar to pollen occurring in Helia and Aripuana. Some similarities are also found with Aripuana cullmaniorum in the presence of dichasial inflorescences, erect flowers, and non-differentiated reticulate pollen tetrads. Phylogenetic studies have shown the distinctiveness of this taxon, as well as the need to move Rogersonanthus coccineus into this new genus. Roraimaea includes two species, Roraimaea coccinea comb. nov. from Serra de Neblina on the Brazil-Venezuelan border, and Roraimaea aurantiaca sp. nov. from lowland, white-sand campinas areas of Roraima State, Brazil.

A new species of the genus Sigmatostalix, S. uncinata, is described and illustrated from the province of Carchi in northern Ecuador. Sigmatostalix uncinata is compared with S. aristulifera, from which it mainly differs by the subquadrate lateral lobes of the lip having an apical, linear, uncinate appendix (vs. narrowly dolabriform and apically emarginate-bilobed); and a semilunate, rounded, concave callus (vs. absent or reduced to a low keel). The phylogenetic position of Sigmatostalix is discussed, and previous infrageneric schemes of classification are reviewed.

Continuing studies of Neotropical Goodyerinae have revealed that three transfers are required in the genus Aspidogyne. Furthermore, the descriptions of 38 new taxa are required in the genera Aspidogyne (3), Kreodanthus (4), Ligeophila (one species, one variety), and Microchilus (28 species, one subspecies). The genus Rhamphorhynchus is considered to be congeneric with Aspidogyne. Microchilus glanduliferus is considered to be conspecific with M. campanulatus. Extensions of distribution are reported for three species. Illustrations are provided for 40 of the 45 taxa treated.

Cardamine tianqingiae (Brassicaceae), a new species from Gansu Province, China, is described and illustrated. Characters that distinguish it from the closely related C. caroides are discussed.

Four new species of Meliosma (Sabiaceae) are herein described and illustrated. Three are from Ecuador: M. condorensis, M. gracilis, and M. palaciosii; and the fourth is from Bolivia, M. caballeroensis.

Three genera are separated here from the South American Capparis s.l. (Capparaceae): (1) Sarcotoxicum, a new monospecific genus restricted to Bolivia, Paraguay, and northern Argentina, composed of Sarcotoxicum salicifolium comb. nov.; (2) Neocalyptrocalyx is validated as a genus of seven species, with the following five species herewith transferred from Capparis s.l.: Neocalyptrocalyx eichleriana comb. nov., N. grandipetala comb. nov., N. leprieurii comb. nov., N. maroniensis comb. nov., and N. muco comb. nov.; and a sixth species, N. longifolium comb. nov., is transferred from Colicodendron; and, (3) Mesocapparis stat. nov., a scandent- shrubby monospecific genus endemic to Brazil, comprised of the new combination Mesocapparis lineata comb. nov. They are characterized by a variously stellate pubescence, 2-seriate sepals, 7 to 37 stamens, and pepos or amphisarca bearing many seeds with white- to cream-colored embryos and convolute cotyledons. Illustrations, descriptions, and a key to the discussed genera are herewith provided.

Nine South American species are transferred from Capparis s.l. to the genera Cynophalla and Calanthea: Cynophalla declinata comb. nov., C. ecuadorica comb. nov., C. guayaquilensis comb. nov., C. heterophylla comb. nov., C. mattogrossensis comb. nov., C. polyantha comb. nov., C. retusa comb. nov., C. tarapotensis comb. nov., and Calanthea stenosepala comb. nov.

A revision of the American species of the genus Crateva (Capparaceae) recognizes four species: (1) C. palmeri, a CentralAmerican species with short, stubby, pubescent inflorescences distinguished by the furfuraceous trichomes, leaflets sessile or with short petiolules to 4 mm, and short axis of infructescences, 1–6 cm. Unpublished isotypes, local names, and uses of C. palmeri are cited herein; (2) the widespread and glabrous C. tapia, ranging form Mexico to Argentina and the Lesser Antilles. Its variable floral morphology is discussed, and local names and uses are also reported for this species. Among its synonyms, Cleome arborea, Crataeva benthamii, and C. radiatiflora are lectotypified, and unpublished types are published for C. benthamii, C. benthamii var. leptopetala, C. radiatiflora, and C. glauca; (3) C. urbaniana, an endemic to Cuba and Dominican Republic, which is characterized by having flowers apetalous and (4−)6(−7) sepals. Unpublished isotypes are also published for C. urbaniana; and, (4) C. yarinacochaensis sp. nov., a local endemic of theAmazonian rainforests around Lago Yarinacocha, an old lake close to the Rio Ucayali ca. 4–6 km NW of Pucallpa, in the Department of Ucayali, eastern Peru. This new species is characterized by the elongate glabrous inflorescences on leafless or new-leaved branches, flowers with linear ovaries, and the fruits are highly distinctive narrowly-oblong or oblong-elliptic pepos with attenuate apex. A generic description and a key for the American species of Crateva is herewith provided.

McIllmurray and Oakeley (2004) demonstrated that the name Maxillaria ramosa has been misapplied to Ornithidium pendulum since 1967, and possibly corresponds to M. cassapensis. We refer Ornithidium ochraceum, O. loefgrenii, and Maxillaria spathulata to the synonymy of O. pendulum (in addition to the already recognized synonyms O. dichotomum and Scaphyglottis tafallae), and designate a lectotype for O. dichotomum. Anew species from Venezuela and the Guianas (Ornithidium elianae), previously confused with O. pendulum, is described. An updated description of O. pendulum is presented along with a review of its complicated taxonomic history and the first record of this species for Costa Rica.

The rediscovery of Trichospermum pseudojavanicum and Glochidion rugulosum is discussed in a series of short notes from the Conservation International 2007 Mamberamo Expedition. Diagnostic and characteristic structures, many previously unseen, are depicted with a comprehensive selection of in situ color photographs.

The tribes Aphragmeae and Conringieae are proposed as new, and the tribes Biscutelleae, Calepineae, and Erysimeae (Brassicaceae; Cruciferae) are re-established. The unigeneric Aphragmeae, Biscutelleae, and Erysimeae include the genera Aphragmus, Biscutella, and Erysimum, respectively. The Conringieae comprises Conringia and Zuvanda, whereas the Calepineae includes Calepina, Goldbachia, and Spirorrhynchus. The prior tribal assignments of these genera, total number of species, and geographic distribution of all five tribes are listed.

Selected Sellaphora species from rivers and springs of the southeastern United States were studied by light (LM) and scanning electron (SEM) microscopy. Three new species are described here and two new combinations are made. Besides the traditional morphological characters, additional morphometric data were used to delineate species. Sellaphora hohnii is known only from Silver Springs, Florida, and S. rugula only from a tributary of the Savannah River, Georgia, while S. wallacei and S. meridionalis have wider distributions, but are currently known only from the Southeastern U.S. S. rexii is apparently a globally distributed species. All five species usually have low relative abundances in river samples.

Catasetum moorei was described in 1970 based on a plant collected near Iquitos, Peru. Here we provide a line drawing based on a flower from the holotype and photographs of a plant from Ecuador. Orchid growers and sellers have incorrectly assigned this name to plants of C. discolor, a species from the Guayana Shield (in Brazil, Colombia, Venezuela, and the Guianas) that apparently also occurs in Peru.

A synopsis is presented for the Neotropical genus Cyrtopodium. Type data, taxonomic status, geographical distribution, and nomenclatural and taxonomic notes are presented for each species. A total of 116 names have been proposed in the genus, of which 50 are accepted here (47 species and three subspecific taxa). The identity of five species in the list is unclear. Forty names are synonyms in the genus, five are nomina nuda, and 21 belong in other genera including Eulophia, Koellensteinia, Otostylis, Eriopsis, Tetramicra, and Oncidium. Brazil, with 39 species, is the country with the highest number of species, followed by Bolivia and Venezuela, with nine species each. The main center of diversity of the genus is the cerrado vegetation of central Brazil, were 29 taxa are found. Field and taxonomic research on the genus in the last 15 years has led to the description of 19 new and accepted species, most from central Brazil. Eight lectotypifications and one new synonym are proposed. Cyrtopodium flavum is recognized as the accepted name for C. polyphyllum.