(Rees, 1883)
Kahl, 1932
Body elongate ellipsoidal, posteriorly broadly rounded. Two macronuclei, 2 micronuclei. Contractile vacuole in mid-body on left. One buccal, 3 frontal, 2 frontoterminal and 6-9 (11) transverse cirri in J-shaped row. Two midventral rows (midventral cirral pairs) extend almost to transverse cirri, composed of about 7-15 obliquely arranged cirral pairs. One right and 1 left marginal cirral row, the latter with oblique anterior portion. Caudal cirri lacking. Adoral zone extending over about 40% of body length, composed of 25-28 membranelles of which about first 7 are slightly separated from others. Undulating membranes about 20 µm long. Movement jerking to and fro. Size 45-140 x 20-55 µm. This species differs by the position of the contractile vacuole (in mid-body) from the very similar Holosticha pullaster (in posterior 1/3), with which it is often confused.
Ref.: Kahl (1932), Borror (1963), Borror and Wicklow (1983), Wilbert (1986).