Genus: Cell body short cylindroid in shape, slightly constricted at the center; semicells trapezoid or rectangular in shape, lateral margins smooth or slightly convex; cells firmly attached with each other forming elongate filaments; colonies sometimes covered with thick gelatinous coats (Illustrations of The Japanese Fresh-water Algae, 1977).

H. dissiliens ? 1 clip μm Higashi-hiroshima Hiroshima, 1998	H. dissiliens 1 clip μm Higashi-hiroshima Hiroshima, 1998	H. dissiliens or Cosmarium ? 1 clip μm Higashi-hiroshima Hiroshima, 1998
H. dissiliens 2 clips μm Higashi-hiroshima Hiroshima, 1998	H. dissiliens 4 clips μm Higashi-hiroshima Hiroshima, 1998	H. dissiliens 2 clips μm Higashi-hiroshima Hiroshima, 1998
H. dissiliens 1 clip μm Higashi-hiroshima Hiroshima, 1998