A new genus for the Andean mice Akodon latebricola and A. bogotensis(Rodentia: Sigmodontinae)

Abstract

Akodontini is the 2nd most diverse tribe of Sigmodontinae, which in turn is one of the most speciose groups of muroid rodents. This tribe is among the most poorly understood Neotropical taxa, with most taxonomic problems concentrated in Andean species, especially those inhabiting the northern Andes. Here, applying morphological, morphometric, and phylogenetic analyses (based on 1 mitochondrial and 1 nuclear gene), we review the systematic and taxonomic status of the Bogotá akodont, Akodon bogotensis Thomas, 1895, and the Ecuadorean akodont, A. latebricola (Anthony, 1924) (Cricetidae: Sigmodontinae). Morphometric and morphological analyses give evidence of the morphological distinctiveness of A. latebricola and A. bogotensis. Specifically, these small-sized species present a unique combination of characters that includes soft, grizzled to dark chestnut dorsal fur; dark brown manus, pes, and tail; slender and proportionally long rostra; indistinct zygomatic notches; narrow, backward-sloping zygomatic plates; wedge-shaped infraorbital foramina; proportionally short incisive foramina; inflated braincase and auditory bullae; and opposite molar cusps. In agreement with these morphological results, phylogenetic analyses placed latebricola outside the tribe Akodontini. Based on these results, we propose and describe a new genus for latebricola and bogotensis.