Species diagnosis

General Characteristics

• zygomatic width more than � the length of the skull
• usually lacking a prominent interorbital keel or depression
• zygomatic arches comparitively broad
• m1usually with 5 closed triangles
• length of upper tooth row less than 7mm
• third alternating triangle of M3 usually closed
• anterior loop of m1 more crescent shaped with its labially-directed lobe often forming an incipient sixth triangle

Alaska subspecies