Trinema Dujardin 1841

Two types of tests are common in this genus: a) pouch-shaped, ends round, oval in cross-section, dorsum arched, ventrum flat or concave. (e.g. T. enchelys) and b) in ventral view broad oval, sides parallel, in lateral view tapering sharply towards the aperture. (e.g. T. complanatum). Always two sizes of body scales, large circular plates with smaller circular or broad elliptical scales in between, overlapping. Pseudostome: sub terminal, ventral, round or oval, invaginated, with rows of toothed apertural plates, apertural rim with oval small scales. Vesicular nucleus. Feeding: herbivore. Habitat: common in freshwater, moss and soil. This genus houses more than two dozen species, a similar number of subspecies, varieties and forms. Most of the descriptions are insufficient and should be taken as nomina nuda. Large variability observed in clonal cultures suggest others may be synonyms. Most species are size polymorphic. Type species: Trinema enchelys (Ehrenberg, 1838).

Trinema is a genus of testate amoeba in the phylum Cercozoa. It includes the species Trinema lineare. Species of Trinema are common in freshwater and terrestrial habitats.