Family: Colonies of a fixed number of cells or reticulated bag in shape; chloroplasts plate-like or reticulated, with one or many pyrenoids; asexual reproduction by zoospores, sexual reproduction by fertilization (Illustrations of The Japanese Fresh-water Algae, 1977).
Genus: Colonies large, reticulated bag in shape (Illustrations of The Japanese Fresh-water Algae, 1977).

H. reticulatum 10 clips μm Fujimi Saitama, 1999	H. reticulatum 3 clips μm Fujimi Saitama, 1999	H. reticulatum 3 clips μm Fujimi Saitama, 1999
H. reticulatum 4 clips μm Torinome Kasen p. Nasu-shiobara Tochigi, 1999?