The status of Demodex cornei: description of the species and developmental stages, and data on demodecid mites in the domestic dog Canis lupus familiaris.

Abstract

Demodecosis canina is one of the most important dog parasitoses, but its aetiology is still not well known. There are currently two known species of demodecid mite specific to the domestic dog Canis lupus familiaris Linnaeus, 1758 (Carnivora: Canidae). These are Demodex canis Leydig, 1859 (Acariformes: Demodecidae) and Demodex injai Desch & Hillier, 2003. There have also been many reports of the so-called 'short form', considered to be a separate species functioning under the name Demodex cornei nomen nudum, for which, however, no formal valid description has been documented. Taxonomic analysis of short forms of dog demodecid mites, associated with the stratum corneum, was performed, in line with the taxonomic criteria of Demodecidae systematics. This form was found to be a distinct species with features that differ from those of the other known species of this family. The species, including the adult and immature stages, is described. It is likely that different Demodex species parasitizing the domestic dog may be responsible for differentiated symptoms and different courses of demodecosis. However, the basis for clarifying this issue should be the correct, unambiguous identification of the species causing parasitosis.