New data on Abrawayaomys chebezi (Rodentia, Cricetidae), a poorly known South American sylvan rodent

ULYSES F.J. PARDIÑAS, PABLO TETA , MARCELA LARESCHI AND CARLOS A. GALLIARI

MAMMALIA

WALTER DE GRUYTER & CO

Lugar: Berlin; Año: 2015

0025-1461

Abrawayaomys chebezi is a spiny sigmodontine believed endemic to the Atlantic Forest of Misiones Province, Argentina. The available knowledge is largely restricted to the holotype, the only fully vouchered specimen. Here, we detail a second specimen, a subadult male obtained in the Parque Provincial Urugua- í (Misiones). The morphology of this animal confirms several diagnostic traits of A . chebezi , such as its smaller size relative to Abrawayaomys ruschii , the type species of the genus, and the simplified occlusal structure of its molars. New data on soft anatomy indicate that chebezi has a unilocularhemiglandular stomach, no gall bladder, and a complex tridigitate penis with an external surface covered by rounded spines. A rich parasite assemblage including fleas and mites was recorded from this animal. A preliminary review of the alpha taxonomy of Abrawayaomys suggests the possible existence of three different species in the genus, one still unnamed.