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Most life stages of D. cyonis, including eggs, were found in earwax, whereas juvenile and adult mites were only detected in the outer ear during periods other than the peak infestation period, suggesting that the original habitat site of D. cyonis is the external auditory canal but it can expand to the outer skin in aggravated cases.
References
^ Tatsushi Morita, Aki Ohmi, Akihito Kiwaki, Kazunori Ike, and Katsuyuki Nagata. 2018. A New Stubby Species of Demodectic Mite (Acari: Demodicidae) from the Domestic Dog (Canidae), Journal of Medical Entomology, tjx226, https://doi.org/10.1093/jme/tjx226.