CLASS CHYTRIDIOMYCETES

• Zoospore with a rumposome (a barren basal body parallel to and attached to the active basal body); flagellar roots do not attach to the nucleus; ribosomes aggregated near the nucleus but do not form a nuclear cap; main part of life history is haploid.

• ORDER CHYTRIDIALES
  • Holocarpic or eucarpic with rhizoidal system; zoospore with anterior nucleus, single large lipid droplet, single mitochondrion around the flagellar base, and microtubules in bundle connecting active basal body to the rumposome; zoosporangium spherical or pyriform; germination monopolar; gametes variable.
  • Chytria, Batrachochytridium, Cylindrochytrium, Chytridiomyces, Polyphagus, Synchytrium.

• ORDER RHIZOPHIDIALES
  • Generally holocarpic; nucleus
  • Rhizophidium, Kappamyces, Terramyces, Boothiomyces, Batrachochytrium.

• ORDER SPIZELLOMYCETALES
  • Holocarpic; zoospore with ribosomes dispersed in the cell and basal bodies connected to the nucleus by a striated rhizoplast.
  • Spizellomyces, Powellomyces, Kochiomyces.

CLASS MONOBLEPHARIDIOMYCETES

• ORDER MONOBLEPHARALES
  • Species are eucarpic and filamentous; zoospore with central nucleus; many small lipid bodies, mitochondria and microtubules radiating from the active basal body but not from rumposome; zoosporangia cylindrical or pyriform; oogamous.
  • Monoblepharis, Harpochytridium, Oedogoniomyces, Monoblepharella, Gonapodya.

INCERTAE SEDIS

• Caulochytridium, Olpidium, Rozella, Rhizophlyctis