Rattus elaphinus

Descriptive notes. Head-body 128215 mm, tail 154 - 201 mm, ear 1822.5 mm, hindfoot 34 - 38 mm; weight 123 - 197 g. The Sula Archipelago Rat is medium-sized, with buff soft fur, buff grayish on belly and rufous-buff on back. It has dark tail 93 - 102 % of head-body length and short hindfeet in proportion to head-body length. Palatal bridge extends beyond M’ as inseveral other species of Rattus, postorbital ridge is slightly developed; temporal ridge is also developed toward back of skull; laterally, top of skull is nearly flat (slightly bowed) between nasal and occipital; zygomatic arch is laterally well upon level of upper molar row; posterior palatine foramina is placed in between M * and M ” orat front level of M?; jugular process is moderately developed; in palatal view, squamosal root of zygomatic arch position usually does not overlap with anterior part of tympanic bulla; in palatal view, zygomatic root of zygomatic arch overlaps at the level of M'; eustachian tube is short; post-glenoid vacuity is not fused with middle lacerate foramen in most specimens; basisphenoid seemsto be suspended in spheno-palatine vacuity; posteriorly, incisive foramina reach M' and are wide and long; there four pairs of mammae (one pectoral, one post-axillary, and two inguinal); angular process reaches or slightly extends beyond posterior part ofarticulation condyle and is well-developed; incisors are orange and opisthodont or orthodont; incisor bladeis wide, with size equal or superior to its longest basal width; cusp t 7 is absent on M'; postererocone is absent on M' or rarely forms slight bulge; cusp t 3 is present on M? but is absent on M? in all observed specimens; tl bis is absent on M'; cusp tl of M' is well-separated from cusps t 2 and t 3; antero-central cusplet is absent on M; anteroand postero-labial cusplets are present onM ,, and antero-labial cusplet might be absent; anteroand postero-labial cusplets are present on M,; and antero-labial cusplet on M, might disappearin older individuals.

Sumber: Muridae