Synopsis and systematic reconsideration of Karlingiomyces (Chytridiomycota)

摘要

The genus Karlingiomyces is reviewed and the validity of endo-operculation as a character is questioned in comparison to exo-operculation. Karlingiomyces has been considered an operculate member of the Rhizophlyctis/Karlingia complex, an assemblage of saprotrophic, interbiotic, mostly monocentric Chytridiomycota. Members of this complex have similar thallus morphology, including often more than one discharge pore and several main rhizoidal axes per sporangium. However, a definite exo-operculum delimits Karlingiomyces species from other taxa of the complex. Karlingiomyces contains five species, of which three are chitinophilic and two are cellulosic. One of the cellulosic species, Karlingiomyces exooperculatus, represents a new combination. A key to species of Karlingiomyces, descriptions, illustrations, information on types, and discussions of taxa are provided. Based on probable endo-operculation and on what may be assessed of the zoospore, three other species of Karlingiomyces and one variety are excluded from the genus. Recent morphological and molecular data have cast doubt on the continued inclusion of Karlingiomyces in the Rhizophlyctis/Karlingia complex.