Bazzania (Marchantiophyta) in South America
Gradstein, S. Robbert
Bazzania is the largest genus of the family Lepidoziaceae and considered notoriously difficult in terms of species recognition. About 50 species were recognized in South America by Fulford in her classical treatment of Latin American Bazzania but many of these species have proven to be synonyms. In this paper 30 species are accepted for South America; the South American records of B. cubensis need verification, however. A key to species and brief discussions of the differentiating morphological characters and similarities of the species are provided together with data on synonymy, geographical distribution and habitat. Nine species are reduced to synonymy: B. angustifalcata = B. longistipula, B. arcuata = B. hookeri, B. heterostipa = B. nitida, B. lehmanniana = B. praerupta, B. liebmanniana = B. stolonifera, B. longa = B. praerupta, B. macrostipula = B. falcata, B. schlimiana = B. hookeri, B. taleana = B. affinis. The new combination B. hookeri var. mamillosa (Gradst. & Benitez) Gradst. & Benitez ( = B. arcuata var. mamillosa Gradst. & Benitez) is proposed. The names Bazzania lehmanniana , B. longa and B. tayloriana are excluded from the neotropical flora. Neotropical specimens identified as B. longa, including the types of B. gottscheana and B. speciosum, belong to B. hookeri and the two Colombian records of B. tayloriana, an endemic species from New Zealand, are based on misidentified resp. mislabeled material. Among the countries of tropical America, Colombia with 25 species has the highest diversity of Bazzania followed by Ecuador and Venezuela with 18 species each. About 90% of the species (27) occur in the tropical part of South America and half of them are widely distributed through the Neotropics. Three species ( B. chilensis, B. nitida , B. peruviana ) occur in temperate southern South America and one species ( B. nitida ) has an intercontinental range occurring also in Africa and Australia. The scarcity of intercontinental ranges in Bazzania seems to concur with the rarity of sexual reproduction and spore production in this genus and the absence of asexual propagative devices suitable for long-distance-dispersal.