Abstract Scaphyglottis Poepp. & Endl. (Orchidaceae) is a neotropical genus with 78 species, 14 of which are found in Brazil. Some of these taxa have an intricate taxonomy, especially due to the morphological similarity among species and the existence of species complexes. Our study aims to test if the labellum shape, the main source of species diagnostic characters, can confirm the proposed circumscription of Brazilian species of Scaphyglottis. We analyzed 136 flowers from 12 species, to which we applied 12 landmarks, using a geometric morphometrics approach. Our results show that most species can be distinguished. Most of the variation is observed in the claw and apices of labellum lobes, confirming that the labellum is important tool in taxon distinction. Species with distinctly 3-lobed labellum showed some overlap but, for these taxa, we have found distinction specially in the lateral lobes. Our study showed new morphologically variable features in Scaphyglottis that can be used in future taxonomic studies. For widely distributed species we suggest a population-level approach, as local environmental factors can impact morphology, causing expected intraspecific variation.

Abstract The genus Scaphyglottis Poepp. & Endl. presents 78 species and occurs from Mexico to Brazil. Scaphyglottis punctulata (Rchb.f.) C.Schweinf. is known from various high elevation locations from Panama to Bolivia. Here, we report new records in two regions of the Brazil portion of the Guiana Shield. We provide a detailed description, photographic plates, updated distribution map, ecological and taxonomic comments for S. punctulata, and an identification key for Scaphyglottis species from the Brazilian portion of the Guiana Shield.

Resumo Este estudo apresenta o tratamento florístico das espécies de Vitaceae que ocorrem na Reserva Florestal Adolpho Ducke, Amazonas, Brasil. Coletas provenientes da Reserva Ducke foram analisadas a partir de exsicatas depositadas no herbário INPA. Foram registradas duas espécies do gênero Cissus para a reserva, Cissus erosa e C. verticillata subsp. verticillata. Apresentamos descrições das espécies, comentários taxonômicos, ilustrações, informação sobre hábitat, distribuição geográfica e uma chave de identificação para as espécies.

Abstract This study presents the floristic treatment for the species of Vitaceae occurring in the Reserva Florestal Adolpho Ducke, Amazonas, Brazil. Collections from the Reserva Ducke were analyzed from specimens deposited at the INPA herbarium. Two species of the genus Cissus were recorded, Cissus erosa and C. verticillata subsp. verticillata. We present species descriptions, taxonomic comments, illustrations, habitat information, geographic distribution, and an identification key for the species.