RESUMO Estudos taxonômicos e florísticos no estado do Rio de Janeiro permitiram a redescoberta de Miconia gigantea, uma espécie endêmica da Floresta Atlântica, até recentemente conhecida apenas pelo espécime tipo, coletado há mais de 100 anos por A.F.M. Glaziou. Apresentamos uma descrição emendada e detalhada de M. gigantea, fornecendo características das flores, frutos e sementes, além de ilustrações, comentários sobre afinidades taxonômicas com espécies estreitamente relacionadas, a distribuição atualmente conhecida juntamente com novos registros de ocorrência, e o estado de conservação.

ABSTRACT Taxonomic and floristic studies in the state of Rio de Janeiro allowed the rediscovery of Miconia gigantea, an endemic species to the Atlantic Forest, until recently known only from the type specimen, collected over 100 years by A.F.M. Glaziou. We present an amended and detailed description of M. gigantea, providing characteristics of the flowers, fruits and seeds, in addition to illustrations, comments about taxonomic affinities with closely related species, the presently known distribution together with new occurrence records, and the conservation status.

ABSTRACTPsychotria is the largest Rubiaceae genus and one of the most abundant in the Atlantic Rainforest of Rio de Janeiro State. The present work aims to characterize and compare the wood of nine of these species. ThePsychotria wood were characterized by: slightly distinct growth rings; diffuse porosity; solitary vessels or on radial multiples of 2-6 or clusters of 3-5 vessel elements, with terminal and lateral simple perforation plates and vestured and alternate intervessel and vessel-ray pits; septate fiber-tracheids; and rare axial parenchyma. Although, the wood anatomy of thePsychotria may be considered homogeneous, the statistical analyses, based on qualitative and quantitative features, allowed the segregation of the species and indicated the importance of habit (arboreous or shrubby) on the wood anatomy of the species. It is worth mentioning that the sampling was realized in only one studied site (Ilha Grande), which contributed to the conclusion that the wood characteristics are more related to the specificities of each studied taxon than to with environmental variations.