Protosporangium: a New Genus of Protostelids*

Protosporangium is described as a new genus of the mycetozoan order Protosteliida, with 3 new species: P. bisporum, P. fragile , and P. articulatum . The genus is characterized by minute, mostly 2-4-spored sporangia borne on long, slender, flexuous stalks. The spores produce flagellate cells (typically 8 per sporangium) during germination. The trophic stage is holozoic and uninucleate to plurinucleate but never reticulate. Plurinucleate protoplasts segment into uninucleate (sometimes binucleate) prespore cells that culminate to form sporocarps in the manner characteristic of protostelids.