The flagellate family Peranemidae contains a number of genera which are characterized by the fact that in locomotion the flagellum is held straight anteriorly for about two-thirds of its length and beats only near the tip, thereby giving rise to a smooth "gliding" or "creeping" motion of the organism without rotation or gyration. This type of locomotion is readily noted in the common type genus Peranema. Other characteristics of the genera ordinarily placed in the family are varied (review, Jahn, 1946). Some genera have a rigid body; others are plastic. Some have one or more rod-like structures, the so-called "pharyngeal rods" in the region of the gullet; others do not. Some are holozoic; others are saprozoic. There are even two genera (Distigma and Sphenomonas) ordinarily placed in the family in which the flagellum is not held directly anterior during locomotion. However, this type of flagella activity has not been described in other orders of flagellates, and any flagellate possessing such activity may, at least for the present, be assigned to the family.
Proceedings of the Iowa Academy of Science
©1947 Iowa Academy of Science, Inc.
Shawhan, Fae. M. and Jahn, Theodore L.
"Paraperanema longicauda, n. g., n. sp. (Protozoa; Euglenida; Peranemidae),"
Proceedings of the Iowa Academy of Science, 54(1), 369-371.
Available at: https://scholarworks.uni.edu/pias/vol54/iss1/57