Abstract
We studied the holotype and only known specimen of the rodent Calomys anoblepas Winge, 1887, an enigmatic and putatively extinct pentalophodont sigmodontine found in the limestone caves of Lagoa Santa, Minas Gerais, Brazil. Comparisons with other sigmodontines suggest that anoblepas can be allocated under the genus Juliomys González, 2000 and probably represents an extinct form within it. Cranial characters that support our generic hypothesis include the combination of an interlacrymal depression behind nasals, anterior portion of interfrontal suture with incomplete fusion, zygomatic plate nearly vertical with almost nonexistent upper free border, anterior border of the mesopterygoid fossa located at the level of third molar hypoflexus, and brachyodont molars with crested coronal topography. Juliomys includes three living species of sylvan and arboreal mice endemic of the Atlantic forests. This genus is absent in contemporaneous rodent assemblage from Lagoa Santa area, suggesting different environmental conditions during Pleistocene deposition times.References
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