Genus: Flask-shaped; elongate, flattened; anterior region neck-like; cilia only on right side;
without trichocyst-borders; cytostome with trichocysts; two macronuclei (Kudo, 1966).
Species: Long, thin and contractile; cell body is 200 μm long with a very long and thin neck region and pointed tail; laterally compressed; two macronuclei; a large contractile vacuole with small satellites (Carey, 1992). 500 μm long (Kahl, 1931).
Litonotus cygnus, a dividing cell, x 200, x 400, by Y. Tsukii