The classification of Spizellomyces, Gaertneriomyces, Triparticalcar, and Kochiomyces (Spizellomycetales, Chytridiomycetes)

Abstract

A classification is given for those Chytridiomycetes with monocentric and eucarpic growth forms, endogenous sporangium development, and multipapilliated sporangia that are now known in culture. These belong to six genera which are classified on unique ultrastructural characteristics of the zoospore; however, for convenience of routinely distinguishing these genera, a key is given based on characters detectable by light microscopy. Eight species are described for Spizellomyces, which include S. punctatus (Koch) D. Barr; S. plurigibbosus (D. Barr) comb, nov.; S. kniepii (Gaertner) comb, nov.; S. palustris (Gaertner) comb. nov.; S. acuminatus (D. Barr) comb. nov.; S. dolichospermus sp. nov.; S. lactosolyticus sp. nov.; and S. pseudodichotomus sp. nov. There are two species in Gaertneriomyces: G. semiglobiferus (Uebelmesser) D. Barr and G. tenuis sp. nov. Triparticalcar arcticum (D. Barr) D. Barr and Kochiomyces dichotomus (Umphlett) D. Barr are monotypic genera. Criteria for classifying these fungi in culture are discussed. Rhizophydium and Karlingia are included in the generic key but are not treated at the specific level. This new classification is intended strictly for cultures and neither augments nor replaces earlier and more classical systems.