Gallancyra gen. nov. (Phthiraptera: Ischnocera), with an overview of the geographical distribution of chewing lice parasitizing chicken

The geographical range of the typically host-specifi c species of chewing lice (Phthiraptera) is often assumed to be similar to that of their hosts. We tested this assumption by reviewing the published records of twelve species of chewing lice parasitizing wild and domestic chicken, one of few bird species that occurs globally. We found that of the twelve species reviewed, eight appear to occur throughout the range of the host. This includes all the species considered to be native to wild chicken, except Oxylipeurus dentatus (Sugimoto, 1934). This species has only been reported from the native range of wild chicken in Southeast Asia and from parts of Central America and the Caribbean, where the host is introduced. Potentially, this discontinuous distribution is due to a low tolerance for dry environments, possibly exacerbated by competitive exclusion by Cuclotogaster heterographus (Nitzsch, 1866). Our examinations of O. dentatus also revealed that this species differs significantly from other species of
Oxylipeurus in the male and female genitalia, head structure and chaetotaxy, and other morphological characters. We therefore here erect the monotypic genus Gallancyra gen. nov. for O. dentatus, and redescribe the type species.