A revision of the Macrocheles glaber species group (Acari: Macrochelidae) using phylogenetic systematics

Graduation date: 1985The Macrocheles glaber species group contains many\ud of the common mites which are associated with the dung\ud of domestic animals. Species in the glaber group have\ud been investigated for their use as biological control\ud agents of synanthropic flies.\ud Over 10,000 slide-mounted specimens of Macrocheles\ud in the OSU Acarology Collection and numerous other\ud specimens loaned from around the world, were examined.\ud Twenty-one species described in the literature were\ud reviewed for inclusion in the glaber group. As a\ud result, eight previously described species are\ud redescribed, 11 new species are proposed, and one\ud species is excluded. One misidentification in the\ud literature is corrected. One new synonymy is proposed.\ud The 30 resultant species in the glaber group are divided\ud into ten species complexes arranged in three subgroups\ud defined by shared derived characters.\ud The distributions and phoriont hosts of these 30\ud species are tabulated and anayized. The glaber group\ud has its center of diversity in the Old World Tropics and\ud is distributed in all biogeographic realms except the\ud Neotropical and Antarctic. Populations of Macrocheles\ud perglaber from Oregon and France are interfertile.\ud The species of the glaber group occupy an\ud intermediate position between the primitive free-living\ud members of Macrocheles and the extensive radiation of\ud derived phoretic species. Most species in the glaber\ud group show no specificity in their phoresy on scarab\ud beetles. The paganus-rhodesi cluster, however,is\ud restricted to the tribe Scarabaeini. The dominant\ud morphological trend in the glaber group is the reduction\ud in the degree of sclerotization and ornamentation