Myotis keaysi J.A. Allen, 1914

Novaes, Roberto Leonan M., Claudio, Vinicius C., Diaz, M. Monica, Wilson, Don E., Weksler, Marcelo & Moratelli, Ricardo, 2022, Argentinean Myotis (Chiroptera, Vespertilionidae), including the description of a new species from the Yungas, Vertebrate Zoology 72, pp. 1187-1216 : 1187

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Myotis keaysi J.A. Allen, 1914


Myotis keaysi J.A. Allen, 1914


Medium to large-sized species (FA 38.7-42.0 mm, body mass 6-8 g; Table 6 View Table 6 , Fig. 13 View Figure 13 ), with wooly long fur (LDF 7-8 mm, LVF 5-6 mm). Ears comparatively short (length 11-14 mm). Dorsal fur slightly bicolored, ranging from Mummy Brown and Cinnamon Brown to Ochraceous Tawny, with darker bases. Ventral fur strongly bicolored, with Clove Brown bases, and tips ranging from Ivory Yellow to Light Drab. Membranes and ears are Mummy Brown. Legs and dorsal surface of uropatagium covered by a dense pelage that extends to the knees (or just beyond). A fringe of hairs along the trailing edge of the uropatagium absent. Plagiopatagium attached to feet on the level of the base of the toes by a wide band of membrane. Skull moderate in size (GLS 13.5-13.8 mm, BCB 6.7-6.9 mm), and the rostrum comparatively elongated. The P3 is smaller than P2 and aligned in the toothrow and visible in labial view. Sagittal crest present and varying from low to medium; lambdoidal crests present and ranging from medium to high. Parietal subtly inclined forward in most individuals; posterior region of the braincase rounded and projected beyond the limit of the occipital condyles in most individuals; braincase is narrow in dorsal view; the postorbital and interorbital constrictions are comparatively wide. Specimens from Argentina are smaller and have darker fur than those of the Central Andes.

Endemic to South America and strongly associated with highlands in the Andes, from Venezuela to northern Argentina, where it is present in habitats formed by Dense Ombrophylous Forest, Montana Nebular Forest and, in the areas of higher altitude, in Seasonal Forests dominated by shrubby vegetation and with sparse patches of arboreal vegetation ( LaVal 1973; Moratelli et al. 2019a; Novaes et al. 2021b). In Argentina, it is recorded in Jujuy, Salta, Tucumán, and Catamarca, in Yungas Forest (450-1,700 m; Barquez and Díaz 2020)