Description of Trepomonas

Hexamatine diplomonads, ovoid, bilaterally compressed cells (5-30µm) with 2 lateral locomotory flagella, 2 anterior nuclei and 2 posterior grooves opening on opposed sides of the cell; nuclei crescent shaped and abutting; posterior half of the cell is grooved by 2 largely opened cytostomal depressions or pockets each containing 3 recurrent flagella, 1 of them being longer than others; 2 locomotory flagella beat on each side and propel the cell, which generally move by step-wise rotation; food mostly bacteria ingested at bottom of cytostomal pockets; one contractile vacuole forms in the cell centre and discharges at the posterior end; cysts have been described; free-living but T. agilis also occurs in intestine of amphibia, a marine fish and tortoises.