Genus: Trichome without mucous sheath; straight, long, consisting of numerous cells (Illustrations of The Japanese Fresh-water Algae, 1977).
Species:
O. jovis
3.5-7 x 5 μm
L/W=0.7-1.4
Konuma
Sakado
Saitama, 2004
O. jovis
3 x 4 μm
L/W=0.75
Sukawa-highland
Ichinoseki
Iwate, 2007
O. jovis ?
3-4 x 3-4 μm
L/W=1.0
Hasuda
Saitama, 2002