Basidiocarp development of the cyphelloid gasteroid aquatic basidiomycetes Halocyphina villosa and Limnoperdon incarnatum

Abstract

Basidiocarp structure and development in the aquatic basidiomycetes Halocyphina villosa and Limnoperdon incarnatum were observed under a scanning electron microscope. Halocyphina villosa produces completely closed gasteroid basidiocarps at the early developmental stage while it shows cyphelloid hymenium distribution and ballistosporic basidiospore formation. Alternatively, the basidiocarp of L. incarnatum is cyphelloid at the initial stage but becomes closed at maturity. Basidia and basidiospores are gasteroid and nonballistosporic and are distributed on a loosely formed hymenium. These observations suggest that a cyphelloid hymenomycete and a gasteromycete, terrestrial Basidiomycetes by origin, have evolved into the two aquatic species by now possessing similar closed basidiocarps adapted to aquatic habitats. Key words: Halocyphina villosa, Limnoperdon incarnatum, aquatic basidiomycete, gasteroid basidiocarp.