Family: Frontal cirri differ in size and/or pattern from ventral ones of files; "collar" extends short distance along right edge of body; oral area not U-shaped (Illustrated Guide, 1985). Genus: Many species; usually ovoid or elongate in shape; AZM 1/4 of the body length; two rows of ventral cirri; frontal cirri present (Carey, 1992). Frontventral cirri in zig-zag files; rear rounded, body oval to long (Illustrated Guide, 1985). Species: A common species; anterior rounded, posterior blunted; 300 μm long; peristome 1/4 body length; coloured red or yellow; many macronuclei small & ovoid (Carey, 1992).

50 μm 100 μm 150 μm; x 400

Holosticha polystylata, x 400, x 640, October 1999, Saitama Pref., stained by A. Kihara, photo by Y. Tsukii