Abrawayaomys

Pardiñas, Ulyses F. J., Teta, Pablo & D’Elía, Guillermo, 2009, Taxonomy and distribution of Abrawayaomys (Rodentia: Cricetidae), an Atlantic Forest endemic with the description of a new species, Zootaxa 2128, pp. 39-60 : 41

Abrawayaomys Cunha and Cruz, 1979

Type species. Abrawayaomys ruschii Cunha and Cruz, 1979:2.

Included species. Currently, Abrawayaomys is considered monotypic (see Musser and Carleton, 2005). However, as discussed below, we found morphological differences that allow describing a new species for Argentinean populations. In addition, specimens from Minas Gerais ( Brazil) display a unique set of morphological traits that suggests the existence of a third species.

Emended diagnosis. Medium sigmodontine rodents (total length range 200 ~ 290 mm, condilobasal length range 27 ~ 29 mm) with robust head, rounded small ears, and tail from slightly shorter to moderately larger than combined head and body length; dorsal pelage fully intermixed with grooved spiny hairs; dorsal and ventral pelage colors weakly delimited; rigid tail hairs arranged in sets composed by 5 hairs per scale; short apical tail tuft normally present; pes long with dense ungual tufts longer than claws, short claws, and six plantar pads; skull robust, rounded in outline with short and blunt rostrum, flared zygomatic arches, and inflated braincase; short nasals tapering distally; interorbital region hourglass to partially anteriorly convergent; coronal suture U-shaped; reduced interparietal; large foramen magnum; short incisive foramina; short palate; anterior margin of mesopterygoid fossa rounded, typically without sphenopalatine vacuities; carotid circulatory pattern complete (pattern 1; Voss, 1988); broad and high zygomatic plate; upper incisors narrow but noticeably deep and varying from slightly opisthodont to proodont; small brachyodont molars with main cusps slightly alternate; M1 pentalophodont type with anteromedian flexus barely present and reduced mesoloph fused with paracone; M3 reduced, uniradiculate, and cylindrical in outline; dentary with retromolar fossa enlarged and short angular process; stomach hemiglandular-unilocular.

Distribution ( Fig. 1 ). Abrawayaomys is known from the Brazilian coastal forests, from northeastern to southeastern regions, from Bahia to Rio de Janeiro and from Paraná-Paraíba interior forest in northeastern Argentina. No fossil of Abrawayaomys is known.

Figures

FIGURE 1. Recording localities of Abrawayaomys: A. Argentina: 1, Conjunction arroyo Mbocai and route 12; 2, Eldorado; 3, Montecarlo; 4, Campo Ramón. B. Brazil: 5, Parque Estadual do Rio Doce; 6, São Sebastião das Águas Claras; 7, Reserva Biológica de Forno Grande (type locality of A. ruschii); 8, 6 km SW Viçosa; 9, Aldea Sapucai; 10, Caldas da Imperatriz. Main phytogeographic units recognized for Misiones are indicated: a. Rosewood and Assai Palm Forest; b. Laurel and Guatambu Forest; c. Montaine Araucaria Forest; and d. Montane Forest.