Genus: Postoral kineties usually to left of oral poykinetids (Illustrated Guide, 1985).
Left edge is more curved than right edge; cytopharynx with numerous strong fibrils; ectoplasm with
numerous fusiform trichocysts; macronucleus oval; one to several micronulei (Kudo, 1966).
Species: Ovoid, 60-100 μm long; cytostome ovoid; a single macronucleus and single micronucleus anterior; a single contractile vacuole central; numerous large trichocysts (Carey, 1992). Cell body 60-150 μm long (Kahl, 1930).
F. acuminata var. angusta: Cell body 80-100 μm long (Kahl, 1930).
Frontonia acuminata, stock Kgy-2, stained with Azure C,
cell body μm long, μm wide,
x 640, Yaku island, Kagoshima Pref., Japan, 2001, collected by N. Kinoshita, photo by Y. Tsukii
16 μm 32 μm 63 μm; x 640