Family: Trichome (filamentous structure) lacks heterocysts; with equal diameter throughout whole length;
no hair-like structure; no branching.
(Illustrations of The Japanese Fresh-water Algae, 1977).
Spirulina laxa G.M. West,
cell body μm long, 2 μm wide,
x 640, river bank of Arakawa, near Doman-green Park, Nishi-Urawa, Saitama Pref., Japan, November 2003 by Y. Tsukii
94 μm; x 640