Lophomonas

Flagellate (20-60 µm) with an apical tuft of flagella and an axostyle forming an anterior calyx enveloping the flagellar area, the nucleus, and a part of the parabasal bodies. The calyx is opened along a longitudinal slit, and the trunk of the axostyle is slender and points posteriorly. When the cell divides by a typical pleuromitosis, flagella and axostyle regress and 2 new flagellar areas reform. Ultrastructural studies have shown the 4 privileged basal bodies on one side of the flagellar area; several longitudinal rows of microtubules form the wall of the calyx and the axostylar trunk; in L. blattarum a ring of sausage-shaped dense bodies surround the calyx and correspond to the extracalycial bodies observed by light microscopy; endocommensal parasites in the colon of omnivorous roaches such as Blatta, Periplaneta, and Blatella; form resistant cysts insuring host-to-host transmission; type species P. topocola living in Cryptocercus punctulatus.