Seven new species of <I>Selaginella subg. Stachygynandrum</I> (<I>Selaginellaceae</I>) from Brazil and new synonyms for the genus

Abstract

We describe seven new species of Selaginellasubg.Stachygynandrum (Selaginellaalstonii, Selaginellablepharodella, Selaginellacrinita, Selaginellamucronata, Selaginellamucugensis, Selaginellasaltuicola, and Selaginellasematophylla) from Brazil and discuss their possible affinities and conservation status. Scanning electron micrographs of stem sections, leaves, and spores are provided to illustrate the new taxa. In Selaginellaalstonii and Selaginellasaltuicola vegetative growth from strobilus tips is reported and discussed. Four of the new species are from the Espinhaço Mountain Range associated with Campos Rupestres (montane savannah/rocky fields) vegetation. Three of these (i.e., Selaginellablepharodella, Selaginellacrinita, and Selaginellamucugensis) were collected in the northern part of the range in Chapada Diamantina, state of Bahia, while Selaginellaalstonii is from the southern part of the range in the state of Minas Gerais. Selaginellamucronata is found in Atlantic Rainforest vegetation in the state of Espírito Santo, whereas Selaginellasaltuicola inhabits Cerrado (tropical savannah) vegetation in the state of Mato Grosso. Selaginellasematophylla is the most widely distributed of the new species and was collected in Espírito Santo, Minas Gerais, and Rio de Janeiro states in Campos Rupestres and Atlantic Rainforest vegetation. Selaginellaalstonii occurs in rocky caves, Selaginellablepharodella, Selaginellacrinita, Selaginellamucugensis, and Selaginellasematophylla seem adapted to seasonally dry places, living on sandy or humid soils, Selaginellamucronata occupies humid, forest understory, and Selaginellasaltuicola is adapted to wet places associated with rocks or logs in waterfalls. Of the seven new species, six are considered local endemics (except for Selaginellasematophylla) because of their restricted currently known distributions to one or two localities within a single state in Brazil. Additionally, we propose new synonymy for Selaginellapalmiformis (syn. = Selaginellabahiensissubsp.manausensis, = Selaginellamanausensis) and Selaginellavestiens (syn. = Selaginellafragillima); the last species is endemic to Brazil, recorded in the states of Goiás and Minas Gerais. Finally, based on literature discussed and this study, we conclude that the number of well-documented Brazilian Selaginella species is 61, of which 58 are native and three introduced and naturalized. These statistics are likely to change with further work on Selaginella from Brazil.