Scanning electron microscopy of the tegumental surface of Heterobilharzia americana (Trematoda; Schistosomatidae).

An attempt is made in this paper to define more clearly the tegumental microstructure of the schistosome, Heterobilharzia americana. The adult parasites were examined with scanning electron microscopy at 75-10000 magnifications. The morphology of the oral and ventral suckers, the tegument, and the gynecophoral canal with the in copula female were closely scrutinized. The tegument of the female is simple and uniform in structure, an adaptation which may allow for a more efficient mode of penetration through the smaller mesenteric venules. The male tegument, however, is characterized by papilla-like elevations of irregular size, shape, and distribution. These papillae may represent different kinds of sensory endings.