Family: Test usually more or less compressed; pseudostome narrowly oval or slit-like.
Genus:
(Illustrated Guide 2nd).
Species:
(Illustrated Guide 2nd).
Porosia bigibbosa (Archer 1867) Leidy,
test 280 μm long, 180μm wide, L/W=1.6, pseudostome 72 μm wide,
x 200, x 400, x 640, Kenashitai (marsh), Hakkoda mountain, Aomori city, Aomori Pref., Japan, July 17, 2005 by Y. Tsukii
31 μm
63 μm
94 μm; x 640