PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASfflNGTON 109(4):73 1-743. 1996 Systematics, distribution, and host specificity of Edrabius Fauvel (Insecta: Coleoptera: Staphylinidae) James S. Ashe, Robert M. Timm, and Milton H. Gallardo (JSA) Division of Entomology, Natural History Museum, Snow Hall, University of Kansas, Lawrence, Kansas 66045, U.S.A.; (RJMT) Division of Mammals, Natural History Museum, Dyche Hall, University of Kansas, Lawrence, Kansas 66045-2454, U.S.A.; (MHG) Instituto de Ecologia y Evolucion, Universidad Austral de Chile, Casilla 567, Valdivia, Chile Abstract. — Systematics, distribution, and host relations of the amblyopinine genus Edrabius (Coleoptera: Staphylinidae) are reviewed. Herein, we recognize 1 1 species in the genus Edrabius, all of which are obligate associates of South American caviomorph rodents of the families Caviidae, Ctenomyidae, and Oc-todontidae (Mammalia: Rodentia), and restricted to the southern cone of the continent. Three new species are described: Edrabius grandis (host: Ctenomys coyhaiquensis and C. haigi); Edrabius australis (host: Ctenomys maulinus mau-linus); and Edrabius chilensiformis (host: Octodon degus). New distribution and host records are given for E. alticolus Seevers, E. argentinus Seevers, E. chilensis Scheerpeltz, E. peruanus Seevers, E. philippianus Fauvel, and E. weiseri Seevers. Occurrence of Edrabius on octodontid rodents is reported for the first time {E. chilensis from Aconaemys and E. chilensiformis from Octo-don). The genus Edrabius was formerly known to occur in association with various species of Ctenomys, with the exception of one species, E. kuscheli, associated with Galea musteloides (Caviidae). Resumen. — Se presenta una revision de la sistematica, la distribucion y las relaciones de los hospederos de los amblyopininos del genero Edrabius (Co-leoptera: Staphylinidae). Se reconocen 1 1 especies de Edrabius, todas parasitos obligados de roedores caviomorfos sudamericanos de las familias Caviidae, Ctenomyidae y Octodontidae (Mammalia: Rodentia). Se describen tres nuevas especies: Edrabius grandis, hospedador: Ctenomys haigi); Edrabius australis, hospedador: Ctenomys maulinus maulinus); y Edrabius chilensiformis, hospe-dador: Octodon degus). Se entregan nuevos registros distribucionales y de hos-pederos para E. alticolus Seevers, E. argentinus Seevers, E. chilensis Scheer-peltz, E. peruanus Seevers, E. philippianus Fauvel y E. weiseri Seevers. Por primera vez se reporta la presencia de Edrabius en roedores octodontidos {E. chilensis en Aconaemys y E. chilensiformis en Octodon). El genero Edrabius anteriormente se conocia solamente asociado a diferentes especies de Cteno-mys, con la excepcion de una especie, E. kuscheli, asociada a Galea musteloides (Caviidae). Perhaps the most interesting and enig-are unique members of the family Staphy-matic of all insect-vertebrate interactions linidae because of their obligate association are those of rove beetles of the tribe Am-with mammals; most of the 40,000 de-blyopinini (Coleoptera: Staphylinidae) and scribed species of staphylinids are free-liv-their mammal hosts. Amblyopinine beetles ing predators (Ashe & Timm 1987b). All
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