Character Irenomys Euneomys Neotomys Tail length >HBL <HBL <HBL Palate topography flat, ridged, ridged, uncomplicated foraminated foraminated Premaxillo-maxillary dorso-ventrally sharply sharply suture oriented angled angled Spinous process on absent absent present zygomatic plate Interfrontal present absent present fontanelles Alisphenoid
strut present present (a) absent Facial circulation complete complete incomplete Caecum complex single single Cornified stomach extensive extensive reduced epithelium 2n (FN) 64 (98) (b) 34-36-42 70 (68) (d) (62 to 66) (c) (a) Contrary to the condition noted by Steppan (1995:40), we recorded the alisphenoid
strut in Euneomys as present and bony.
emiliae due to the presence of all the diagnostic characters of the species: reddish-brown dorsal fur, pure white-colored ventral fur, tail (LT) much longer than body (HBL) with LT/HBL ratio of 1.77 (Table 1), the presence of an anteromedial alisphenoid
process on the auditory bullae, interorbital region with beaded supraorbital margins, and the absence of a maxillary fenestra (Fig.