Echinops shakrokii is described and illustrated, and its relationship to the southwestern Asian species of Echinops is discussed. From the southwestern Asian species, E. shakrokii is easily distinguished by its smaller heads, 1.5–2.5 cm in diam., and capitula with 27–33 phyllaries.

Typification of Heliophila brachycarpa, H. florulenta, H. glauca, and H. sclerophylla is established. The second species has been erroneously synonymized with the first for the past 50 years, and the first three are recognized as distinct, whereas the last is reduced to synonymy of the third.

This account reports a journey of ca. 500 km from the city of Inírida to the Colombian basins of the Cuiarí and Isana Rivers (Guianía department) in April–May 2014, the first botanical expedition to this region. This area exemplifies one of the last innermost and botanically unexplored regions of the northwestern corner of the Amazon basin (the upper Río Negro basin), aside from the fieldwork started some 234 years ago with the exploration of the middle and lower portion of the Isana basin in Brazil (where it is called Içana) by the Portuguese naturalist Alexandre Rodrigues Ferreira. On our expedition we collected 1301 botanical numbers, which resulted in eight new species (two already published), two new families, and 24 species new to the Flora of Colombia. Another noteworthy feature is the high diversity of the forests in the upper Isana River, represented by between 108 and 162 spp. with a diameters ≥ 2.5 cm in different 40 × 40 m plots (1600 m²). The Isana River is a white-water basin (with high levels of sediments), with large areas covered by the vegetation typical of black-water rivers (Amazon Caatinga forests, lower forests, savannas and sclerophyllous shrubby vegetation over white-sand soils). This feature results from the influence of several black-water rivers, the headwaters of which drain from Precambrian Guiana shield outcrops. This account of the first botanical exploration in the Colombian portion of the Cuiarí and Isana Rivers is yet another example of the need for continued floristic studies in regions where there are large geographic gaps in the knowledge of Amazonian flora. Advances in documentation of this flora can be achieved through institutional and private partnerships, improved training, and continued fieldwork in collaboration with local inhabitants. A discussion of demarcation issues regarding the frontier between Brazil and Colombia in this northwestern corner of the Amazon basin, its physical and biological environments, and its ancestral and current inhabitants is presented.

The Viruá National Park (VNP) with its different plant formations (rainforest, white-sand savannas —“campinaranas,” and “buritizais”) is located in a region still lacking in botanical studies (Guiana Shield and Brazilian Amazon). Aiming to improve the knowledge of the region's flora, collections were conducted in VNP from 2010 to 2015. The present work provides a taxonomic treatment of the aquatic and palustrine members of Nymphaeales, Alismatales, Dioscoreales, and Arecales. It includes identification keys to species, as well as descriptions, illustrations, and comments on taxonomy, ecology and geographical distribution. A dichotomous key to all families with at least one aquatic or palustrine species found in VNP is also provided.

Since its description almost 40 years ago, the mistletoe Cladocolea biflora (Loranthaceae) has been considered an extraordinary species due to its combinations of unique morphological characters, which made it difficult to confidently assign it to any of the extant genera of Neotropical Loranthaceae. In this contribution, we propose that the specimen from which C. biflora was described does not represent a mistletoe but instead the hemiparasitic tree Schoepfia schreberi (Schoepfiaceae). Morphological characters evaluated to justify this decision and taxonomic implications are discussed, and a synonymization of C. biflora under S. schreberi is proposed.

Two new species of Rubiaceae (Condamineeae) are here described and illustrated. Pentagonia baumannii is a shrub endemic to the lowlands of northwestern Ecuador. The second novelty is P. carniflora, an unbranched to few-branched pachycaule tree restricted to the eastern lowlands of the Departments of Antioquia and Caldas in northwestern Colombia. The relations of both species with their closest relatives are discussed.

Several new combinations were recently proposed to merge species of Rheedia into Garcinia. Because some species were not part of larger taxonomic treatments, revisions, or local floras, new combinations for them were not proposed. Garcinia martinii is a new combination based on the basionym Rheedia martinii, an Amazonian tree species from the high mountains of Suriname, in South America.

Subtribe Espeletiinae (Asteraceae) represents the best example of morphological and ecological diversification in the Northern Andes high-elevation ecosystem known as páramo. These plants, formerly considered as belonging to a single genus, Espeletia, were later referred to eight genera defined mainly according to their habit, branching pattern, and inflorescence position and structure. However, several molecular phylogenetic analyses have shown that this classification system is artificial since the larger genera, regrouping ca. 85% of the species, are polyphyletic. Here, a return to the previous classification system of the subtribe at the generic level is proposed, adopting the view that only Espeletia should be recognized, with the other seven genera considered as (heterotypic) synonyms. At the species level, a taxonomic revision is made of the nomenclature, morphology, and distribution of the taxa in the Venezuelan clade of Espeletia, one of the two major clades that compose the genus. Fifty-four species are accepted, 48 entirely endemic to the Venezuelan Cordillera de Mérida, 2 broadly distributed in this range and nearby areas in Colombia and Venezuela, and 4 endemic to the northern section of the Colombian Cordillera Oriental and Sierra de Perijá. Distribution maps for all species are proposed, along with brief morphological descriptions and lists of diagnostic features that facilitate their identification against similar species. Thirteen hybrid taxa and their putative parental species are also given, eight of them proposed here for the first time.

Three new combinations in Myriopus (Heliotropiaceae) endemics from Brazil are proposed in this paper: Myriopus gardnerianus, M. membranaceus and M. salicifolius.

Two new combinations in Euploca (Heliotropiaceae) from Marquesas Islands, endemic from French Polynesia, are proposed in this paper: Euploca marchionica and Euploca perlmanii.

Two new species from the Brazilian Atlantic rainforest of Espírito Santo State, Licaria spiritusanctensis and Ocotea teresae, are described and illustrated. Their putative relationships within the respective genera are discussed. We also provide illustrations and comments on micromorphological and anatomical features of leaves of these new species, comparing them to those of congenerics and showing that they can be useful for recognition of different taxa.

Hedyosmum guaramacalense, found in montane forest (1600–2600 m) on the south slope of Guaramacal National Park, Trujillo state, Venezuela, is described and illustrated. The new species belongs to H. subgenus Tafalla section Microcarpa and is similar to H. goudotianum var. goudotianum, but can be distinguished by its elliptic or narrowly elliptic, coriaceous or chartaceous leaves, scabrous above and below, with 5–8 lateral nerves; strigose or floccose petiolar sheaths with fimbriate appendages either restricted to two patches or evenly distributed along the apical margin; and staminate inflorescences in a cyme with 2–3 spikes, each spike 1–5 cm long. A key to the species of Hedyosmum currently known in the Venezuelan Andes also is provided.

Literature and herbarium studies of various orchid taxa that occur in the New World lead to the recognition of two new species and five new synonyms, and the transfer of two names. Thus two transfers are proposed, Bifrenaria parthonii and Ida insolita, and two new species are proposed, Microchilus croatii and M. topoensis.

Three Malesian species of Dendrobium are discussed regarding their typification and identity. Thus D. curvum is found to be based on a mixture and after lectotypification is proposed as the earlier name for D. rappardii; the previously obscure D. dactyliferum is found to be an earlier name for D. pandaneti; and D. triflorum is found to be a commonly misapplied name, which after typification is proposed as a synonym of D. geminatum.

Herbarium and literature studies of various orchids from the Malesian floristic zone reveal some new species, synonymy, and the need for a few nomenclatural proposals. Thus, the synonymy of Cestichis halconensis is elaborated; Cymboglossum is found to be the older name for Ascidieria, requiring 8 transfers; Dendrobium appendiculoides is reduced to D. zamboangense; Dendrobium philippinense is reduced to D. gerlandianum; Epidendrum subulatum is reduced to Thrixspermum filiforme; Eria section Polyura is transferred to Pinalia; Eria villosissima is transferred to Mycaranthes; and Myrmechis philippinensis is renamed Odontochilus marivelensis. Six new species are proposed, namely, Dendrobium rubroflavum, Pinalia edanoana, P. kitangladensis, P. pentalopha, P. sanguinea, and P. tonglonensis.

The new genus Pridgeonia, and eight new orchid species in the genera Benzingia, Daiotyla, Dichaea, Ixyophora, and Pridgeonia, all belonging to the subtribe Zygopetalinae, are described. Complete descriptions, with notes on etymology, habitat, and ecology, and discussion of phylogenetic affinities, are provided for each new taxon, supplemented with line drawings, photographs, digital composite plates, and distribution maps. New combinations and synonyms are proposed in the genera Aetheorhyncha, Benzingia, Dichaea, and Ixyophora. Dichaea dressleri and Kefersteinia alata are recorded and illustrated for the first time for the flora of Costa Rica. Keys for the genus Benzingia and the Costa Rican species of Dichaea are proposed.

A new species of Eperua from the upper basin of the San Miguel River, Amazonas state, Venezuela, is described and illustrated. Its affinities within the genus are discussed and an updated key to identify the 20 currently recognized taxa is provided.

We discuss nomenclatural and taxonomic matters pertaining to three species of Cyperus subg. Diclidium (Schrad. ex Nees) C. B. Clarke, viz., C. acicularis (Schrad. ex Nees) Steud., C. flexuosus Vahl, and C. macrocephalus Liebm. We examined the relevant available type materials of the three species and their associated synonyms. Our study shows that based on priority, the names C. ferax Rich. and C. conglobatus Link replace C. flexuosus and C. macrocephalus, respectively. For C. acicularis, a later homonym (non (L.) With.), C. strongii G.C. Tucker & Gandhi is proposed as the replacement name. A key is provided for identification of all the Cyperus subg. Diclidium species occurring in the New World.

Meconopsis castanea and the related M. georgei and M. bijiangensis are revised, and a related new species, M. atrovinosa, is described and illustrated. A distribution map of the treated species is provided.

Meconopsis section Forrestianae is revised. Three new species, M. aprica, M. purpurea, and M. wengdaensis; two new subspecies of M. lancifolia, subsp. daliensis and subsp. shikaensis; and a new variety of M. yaoshanensis, var. luojiensis, are described and illustrated. A new combination is proposed, Meconopsis lancifolia subsp. xiangchengensis. Distribution maps of the taxa treated are provided.