Genus: Ovoid, firm; dorsal side convex, ventral side flattened; dorsal surface ridged;
adoral zone reduced or rudimentary; macronucleus U-shaped or in two rounded parts (Kudo, 1966).
Species: |
A. costata (Dujardin, 1842 ?) Kahl, 1932 (synonym: A. cicada ?): Ovoid; 25-40 μm long, 17-28 μm wide; outline smooth but posterior swell; 6 longitudinal dorsal ridges; 7 frontoventral, 5 transverse cirri; macronucleus horseshoe-shaped; fresh water (Gensei-dobutu-zukan, 1981).
A. cicada (Müller, 1786) Claparède and Lachmann, 1858 (Syn. Aspidisca costata (Dujardin, 1841 ?) Stein, 1859; Aspidisca sulcata Kahl, 1930-5): Ovoid; 45 μm long; outline smooth but posterior swell; longitudinal dorsal ridges vary in shape and number; 7 frontoventral, 5 transverse cirri; macronucleus C-shaped (Carey, 1992).
A. polypoda (Dujardin, 1841) Kahl, 1930-5: Ovoid; 55 μm long; outline smooth but 7-8 dorsal ribs; 7 frontoventral, 6 transverse cirri; macronucleus horseshoe-shaped (Carey, 1992).