Morphological studies on the microfilariae of Onchoceca Gibsoni cleland & Johnston and Onchocerca gutturosa Neumann (nematodaL Filaroidea).

Abstract

Studies have been made on the morphology of the microfilariae of Onchocerca gibsoni Cleland & Johnston, and 0. gutturosa Neumann. Examinations were initially made on larvae emerging from dissected female worms, and later, on larvae recovered from the skin. No differences in either morphology or body length measurements were detected between the skin-inhabiting and freshly emerged larvae of each species. The form, size, and arrangment of the caudal and cephalic nuclei were found to vary widely within each species. Of the many measurements investigated only that of body length had any taxonomic value. Skin-inhabiting microfilariae of 0. gibsoni had a body length of 240- 280 � (mean 266 �), whereas those of 0. gutturosa measured only 200-260 � (mean 224.5 � ), the difference between the means being highly significant.