Demodex canis

Demodex are tiny, wormlike mites, with short, stubby legs ending in small blunt claws. 
Demodex mites are a specialized group of parasitic mites that live in the hair follicles and sebaceous glands of various mammals. The Demodex canis  is a normal inhabitant of the skin of most dogs and the researches have led to the hypothesis that generalized demodicosis results from hereditary immunologic  defects that allows mites to proliferate.
Skin scraping. 
In addition to the adult forms, fusiform eggs, six-legged larvae, and eight-legged nymphs are visible in skin scrapings.