Sarcoptes

Sarcoptes
Phylum	Arthropoda
Class	Arachnida
Order	Sarcoptiformes
Family	Sarcoptidae
Genus	Sarcoptes
Species	S.scabei

Sarcoptes scabei - Kalumet 2004,Wikimedia Commons

Sarcoptes scabei - Kalumet 2004,Wikimedia Commons

Scabies on human skin resulting in pruritus - Geary 2006,Wikimedia Commons

Sarcoptes mites are burrowing mites of dogs and foxes. They Cause Sarcoptic Mange. The mites prefer hairless skin and so begin on the hocks, elbows and pinnae. The mites are usually spread by direct host to host contact.

Identification

Sarcoptes mites are small, round mites. They have short legs that project only a short distance from the body margin. They have dorsal spines arranged in rows and a terminal anus. The male mites are about 250μm in length and the females are about 400-430μm in length.

Life cycle

Sarcoptes mites have a 3 week life cycle. The female lays eggs in the epidermis in an egg laying pocket. The female feeds on liquid oozing from damaged tissue. The eggs then hatch in 1 week and 6 legged larvae are released. They crawl to skin surface and then burrow back into the epidermis into moulting pockets. The larvae moult to become 8 legged nymphs. The nymphs moult twice before becoming adults. Adult males then emerge and look for females to mate.

Diagnosis

Mite infection can be diagnosed with a skin scrape of a 'non-scratched' region. The presence of one Sarcoptes mite is diagnostic.