Oncocerca volvulus

Onchocerca volvulus. Microfilaria teased from skin snip (hematoxylin stain, high power). This large microfilaria lacks a sheath. The column of nuclei may be densely packed and deeply stained. The cephalic space is larger than it is wide, and the nerve ring space is well-demarcated. The column of nuclei does not extend to the end of the body; the terminal portion of the tail, which is devoid of nuclei, is usually flexed but may be difficult to see in some preparations.