The Brazilian species of Elaphoglossum section Squamipedia (Dryopteridaceae)

Abstract

A taxonomic treatment for the three species of Elaphoglossum sect. Squamipedia found in Brazil is presented. The section is monophyletic and most of its species are characterized by slender, 1–1.5 mm wide, long-creeping stems; the presence of two peg-like aerophores on the rhizome just behind each petiole; pale brown stem scales; the absence of phyllopodia and hydathodes; and echinulate spores. Elaphoglossum peltatum is unique among the Brazilian species of the genus by having sterile leaves with divided laminae. Within the country, E. minutum is known from only two gatherings made in the state of Goias, where it grows in gallery forests around 700 m. Elaphoglossum peltatum is found on the mountains of the northern Amazon and disjunctly in eastern Brazil, from 800 to 2000 m. Elaphoglossum squamipes occurs on the coastal mountains of Serra da Mantiqueira and Serra do Mar, where it grows in cloud forests above 800 m. None of the three species is endemic to Brazil. We provide identification keys, descriptions, synonyms, comments, line drawings, spore images, distribution maps, and an index of herbarium vouchers to all species accepted in this treatment. A lectotype is designated for Acrostichum craspedariiforme and a second-step lectotype for Osmunda peltata. Additionally, E. ovatum is here excluded from the Brazilian flora.