Family: Unicells or cells loosely attached forming hyphae; cell body varied in shape, a constriction at the center in most species; cell walls consisting of two or more parts, with small pores and various ornaments (Illustrations of The Japanese Fresh-water Algae, 1977).
Genus: cell body flat, constricted at the center; semicell ellipsoidal or subtriangular, central area of the apex slightly elevated, cells connected with each other at their central area of apex forming filament.
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Similar genus -->> Sphaerozosma; Onychonema;
S. javanicum
31 x 24 μm
Kasuga
Fukuoka, 2001
S. javanicum
26 x 21 μm
Kabuto-yama
Nishi-no-miya
Hyogo, 2004
S. javanicum
30 x 25 μm
water reservoir
Yamaguchi Univ.
Yamaguchi, 2004
S. planum ?
12.5 x 15 μm
Nishi-nasuno
Tochigi, 2001
Spondylosium sp. ?
15 x 12 μm
Sanda
Hyogo, 2001
S. pulchellum ?
or Cosmarium ?
14 x 11 μm
Kayoicho-ike
Fukuoka, 2001