Character states listed here pertain to British Columbia specimens and are not necessarily diagnostic for a given taxon worldwide. If accurate diagnosis is required for legal or research purposes, an expert should be consulted. Distinctions among skulls based only upon the characters listed here may not always be reliable due to the presence of outliers, mutations, tooth wear, immaturity, and unsampled geographic variation. Skulls found in the field may be damaged due to the effects of predators, scavengers, gunfire, and weathering. For example, most deer skulls lack premaxillae, and mandibles may be widely separated from crania. Skulls harvested from raptor pellets may be incomplete, and specimens retrieved from carnivore feces may include only bone fragments.

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Order DIDELPHIMORPHIA (Opossums)

5134/4134 Palatine fenestrated; five upper incisors and four lower incisors per side (ten upper and eight lower in total); angular process inflected; nasals expanded caudally; jugal contributes to mandibular fossa.

Family Didelphidae (Opossums)

Didelphis virginiana (Virginia Opossum)

Order LAGOMORPHA (Rabbits, Hares and Pikas)

Total of two prominent anterior grooved upper incisors overlapping a pair of small peg-like incisors; diastema between incisors and cheek-teeth; maxillae fenestrated; mandibular coronoid process united with condyle.

Family Ochotonidae (Pikas)

Supraorbital process absent; five upper cheek-teeth; jugal extends as a long spur caudally beyond zygomatic arch almost to external auditory meatus.

Ochotona collaris (Collared Pika)

2132/1023 Tympanic bulla usually > 25% skull length.

Ochotona princeps (American Pika)

2132/1023 Tympanic bulla usually < 25% skull length.

Family Leporidae (Rabbits and Hares)

Maxilla latticed; supraorbital process present; six upper cheek-teeth.

Genus Lepus (Hares and Jackrabbits)

Interparietal not distinct.

Lepus americanus (Snowshoe Hare)

2033/1023 Upper row of cheek-teeth < 16.0 mm. Lepus townsendii (White-tailed Jackrabbit)

2033/1023 Upper row of cheek-teeth > 16.0 mm; lateral flange on jugal prominent.

Genus Sylvilagus (Cottontails)

Interparietal distinct.

Sylvilagus floridanus (Eastern Cottontail)

2033/1023 Upper row of cheek-teeth > 14.0 mm; external auditory meatus diameter < combined length of last three upper cheek-teeth.

Sylviligus nuttallii (Mountain Cottontail)

2033/1023 Upper row of cheek-teeth < 14.0 mm; external auditory meatus diameter > combined length of last three upper cheek-teeth.

Order RODENTIA (Rodents)

Total of two prominent upper and two prominent lower incisors; significant diastema between incisors and cheek-teeth.

Family Aplodontidae (Mountain Beavers)

1023/1023 First cheek-tooth a small peg; remaining upper cheek-teeth round with projections on labial side; lower cheek-teeth with projections on lingual side; Bulla with long neck; frontals constricted at rostral zygomatic root; zygomata widest caudally; mandibular angle wide and inflected; postorbital processes absent.

Aplodontia rufa (Mountain Beaver)

Family Sciuridae (Squirrel Family)

Postorbital processes distinct; infraorbital foramen tiny; jugals long, usually in contact with lacrimals; palatines ridged.

Genus Sciurus (Tree Squirrels)

Zygomata nearly parallel; zygomatic plate ascends at angle of about 50 degrees; interorbital breadth about equal to postorbital breadth; rostral border of orbit opposite third-to-last upper cheek-tooth; two bullar septa; mandibular coronoid process short.

Sciurus carolinensis (Eastern gray Squirrel)

1023/1013 Usually 5 upper cheek-teeth.

Sciurus niger (Eastern Fox Squirrel)

1013/1013 Usually 4 upper cheek teeth.

Genus Marmota (Marmots)

Cranium dorsally-flattened; postorbital processes robust and perpendicular to long axis of cranium; temporal lines distinct, V-shaped, union may form mid-sagittal crest; upper row of cheek-teeth > 18.5 mm.

Marmota caligata (Hoary Marmot)

1023/1013 Upper row of cheek-teeth > 21.2 mm; frontonasal suture does not form rostrad-V.

Marmota flaviventris (Yellow-bellied Marmot)

1023/1013 Row of upper cheek-teeth < 21.2 mm.

Marmota monax (Woodchuck)

1023/1013 Upper tooth rows parallel, not diverging rostrad.

Marmota vancouverensis (Vancouver Marmot)

1023/1013 Upper row of cheek-teeth > 21.2 mm; frontonasal suture forms rostrad-V.

Genus Spermophilus (Ground Squirrels)

Zygomata not parallel; dorsal surface of cranium caudally arched downward; zygomatic plate ascends at angle of about 40 degrees; postorbital width > interorbital width; five upper cheek-teeth; mandibular coronoid process prominent.

Spermophilus columbianus (Columbian Ground Squirrel)

1023/1013 Upper row of cheek teeth >10.0 mm.

Spermophilus lateralis (Golden-mantled Ground Squirrel)

1023/1013 Upper row of cheek teeth <10.0 mm.

Spermophilus parryii (Arctic Ground Squirrel)

1023/1013 Upper row of cheek teeth >10.0 mm.

Spermophilus saturatus (Cascade Golden-mantled Ground Squirrel)

1023/1013 Upper row of cheek teeth <10.0 mm.

Genus Tamias (Chipmunks)

Infraorbital foramen, not canal, present.

Tamias amoenus (Yellow Pine Chipmunk)

1013/1013 Upper row of cheek teeth < 6.0 mm; skull usually < 32.5 mm; mandible >17.5 mm.

Tamias minimus (Least Chipmunk)

1013/1013 Upper row of cheek teeth < 6.0 mm; skull usually < 32.5 mm; mandible <17.5 mm.

Tamias ruficaudus (Red-tailed Chipmunk)

1013/1013 Upper row of cheek teeth < 6.0 mm; skull usually <32.5 mm; mandible >17.5 mm.

Tamias townsendii (Townsend's Chipmunk)

1013/1013 Upper row of cheek-teeth > 6.0 mm; skull>37.0 mm.

Genus Tamiasciurus (Red Squirrels)

usually 1013/1013 Zygomata parallel; zygomatic plate ascends at angle of about 50 degrees; interorbital breadth about equal to postorbital breadth; three bullar septa visible; rostral border of orbit rostrad to third-to-last upper cheek-tooth.

Tamiasciurus douglasii (Douglas's Squirrel)

Tamiasciurus hudsonicus (Red Squirrel)

Glaucomys sabrinus (Northern Flying Squirrel)

1023/1013 Zygomata not parallel; interorbital margin V-shaped when viewed from below; zygomatic plate ascends at an angle of about 65 degrees.

Family Castoridae (Beavers)

1013/1013 A large rodent skull; basioccipital has depression when viewed from ventral side; infraorbital foramen smaller than incisive foramen; bulla with elongated neck; jugal expanded rostrad and in contact with lacrimal; mandible has distinct process on ventral border behind symphysis.

Castor canadensis (American Beaver)

Family Dipodidae (Jumping Mice)

Large oval infraorbital foramen, about as large as external narial cavity; nasals project beyond incisors; first upper cheek-tooth minute; upper incisors grooved.

Zapus hudsonius (Meadow Jumping Mouse)

1013/1003 Small, narrow skull, first upper cheek-tooth small, cheek-tooth row < 3.7 mm; incisive foramen < 4.2 mm.

Zapus princeps (Western Jumping Mouse)

1013/1003 First upper cheek-tooth small, cheek-tooth row > 3.7 mm; incisive foramen > 4.2 mm.

Zapus trinotatus (Pacific Jumping Mouse)

1013/1003 Broad skull, large angle between condyle and coronoid; first upper cheek-tooth large, with labial re-entrant fold forming crescent-shaped loop (unreliable).

Family Muridae (Rats, Mice, Voles)

Infraorbital canal widest dorsally, pear-shaped or V-shaped or key-hole shaped; zygomatic plate wide.

Neotoma cinerea (Bushy-tailed Woodrat)

1003/1003 Zygomatic plate extending rostrad, creating distinct zygomatic notch; cheek-teeth semiprismatic.

Genus Peromyscus (Deer Mice)

1003/1003 Cheek-teeth cuspidate in two rows; zygomatic plate extending rostrad, creating zygomatic notch; coronoid process usually as low or lower than condyle, lower border of mandibular ramus straight or convex.

Peromyscus keeni (Columbian Mouse)

Peromyscus maniculatus (Deer Mouse)

Reithrodontomys megalotis (Western Harvest Mouse)

1003/1003 Upper incisors grooved; cheek-teeth cuspidate; zygomatic notch very prominent; bullae moderately inflated.

Genus Microtus (Meadow Voles)

Cheek-teeth prismatic; labial and lingual re-entrant angles similar in depth; nasals do not project beyond incisors; caudal edge of palate with median ridge, not plate.

Microtus longicaudus (Long-tailed Vole)

1003/1003 Nasals hide incisiors when viewed from above; incisive foramina tapered gradually if at all.

Microtus montanus (Montane Vole)

1003/1003 Incisive foramina constricted caudally.

Microtus oeconomus (Tundra Vole)

1003/1003 First lower cheek-tooth has four closed angles.

Microtus oregoni (Creeping Vole)

1003/1003 First lower cheek-tooth with five closed triangles, third upper cheek-tooth with three lingual salient angles.

Microtus pennsylvanicus (Meadow vole)

1003/1003 Second upper cheek-tooth has 4-enclosed sections plus rounded posterior loop.

Microtus richardsoni (Water Vole)

1003/1003 Incisors protrude well-beyond nasals; first lower cheek-tooth with five closed triangles, thrird upper cheek-tooth with four lingual salient angles.

Microtus townsendii (Townsend's Vole)

1003/1003 Incisive foramina tapered caudally but not constricted to narrow slits; third upper cheek-tooth has four lingual salient angles; incisors visible beond nasals when viewed dorsally.

Ondatra zibethicus (Muskrat)

1003/1003 Cheek-teeth prismatic; labial and lingual re-entrant angles similar in depth; incisors protrude somewhat beyond nasals; interorbital region strongly constricted; greatest length of skull > 52 mm.

Phenacomys intermedius (Western Heather Vole)

1003/1003 Cheek-teeth prismatic; caudal edge of palate with spinous process; lingual re-entrant angles of lower cheek-teeth disproportionately large.

Genus Myodes (red-backed Voles)

Cheek-teeth prismatic; caudal edge of palate a shelf; lingual re-entrant angles of lower cheek-teeth similar in depth to labial re-entrant angles.

Myodes gapperi (Southern Red-backed Vole)

1003/1003 Palatal shelf bridges postnarial cavity.

Myodes rutilus (Northern-Red-backed Vole)

1003/1003 Palatal shelf incomplete laterally.

Synaptomys borealis (Northern Bog Lemming)

1003/1003 Cheek-teeth prismatic; upper incisors grooved; re-entrant angles disproportionately deep on labial side of upper cheek teeth and on lingual side of lower cheek teeth.

Lemmus trimucronatus (Brown Lemming)

1003/1003 Cheek-teeth prismatic; skull robust; interorbital region narrow; zygomata flared; tooth rows divergent rostrad; re-entrant angles disproportionately deep on labial side of upper cheek teeth and on lingual side of lower cheek teeth.

Mus musculus (House Mouse)

1003/1003 Cheek-teeth cuspidate in three rows; incisors with caudal subapical notch; first upper cheek-tooth longer than combined length of next two; palate terminates well behind cheek-teeth; zygomatic notch present; angular process is caudal-most part of mandible, coronoid process higher than condyle; lower border of mandibular ramus below cheek-teeth concave.

Genus Rattus (Old World Rats)

1003/1003 Cheek-teeth cuspidate in three rows; incisors lacking caudal subapical notch; first upper cheek-tooth shorter than combined length of next two; zygomatic notch present.

Rattus norvegicus (Brown Rat)

1003/1003 Temporal ridges parallel along parietals, parietal length along ridge > distance between ridges.

Rattus rattus (Black Rat)

1003/1003 Temporal ridges curved along parietals; parietal length along ridge < distance between ridges.

Family Geomyidae (Pocket Gophers)

1013/1013 First upper cheek-tooth largest in row and 8-shaped; last cheek-tooth larger than previous; temporal ridges prominent; two pits in palate opposite last cheek tooth; interorbital width < width of rostrum; palatopterygoid plate on each side of internal nares; mandible with incisor root process between angular process and condyle.

Thomomys talpoides (Northern pocket Gopher)

Family Heteromyidae (Pocket Mice)

1013/1013 upper incisors grooved; infraorbital canal pierces rostrum; zygomata delicate; bullae inflated, almost meeting rostrad; premaxillae form basal shelf anterior to incisors; interorbital width > width of rostrum; nasals long and narrow.

Perognathus parvus (Great Basin Pocket Mouse)

Family Erethizontidae (Porcupines)

Erethizon dorsatum (North American Porcupine)

1013/1013 Large rodent skull; infraorbital foramen larger than foramen magnum; jugal not in contact with lacrimal; mandibular condyle higher than coronoid process.

Order EULIPOTYPHLA (Moles and Shrews)

Small delicate pointed elongate triangular skull; first upper incisor prominent; complete tooth row; zygomata may be absent.

Family Talpidae

Teeth not pigmented; delicate zygomata present; tympanic bulla present; molars dilambdodont.

Genus Scapanus (Western American Moles)

Bulla complete.

Scapanus orarius (Coast Mole)

3143/3143 Palatal length < 16 mm.

Scapanus townsendii (Townsend's Mole)

3143/3143 Palatal length > 16 mm.

Neurotrichus gibbsii (American Shrew Mole)

3123/3123 Bulla only a partial ring.

Family Soricidae (Shrews)

Tips of teeth pigmented reddish-brown; zygomata absent; bulla absent; tympanic annular; first upper incisor large and hooked.

Sorex arcticus (Arctic Shrew)

1513/1113 Five upper unicuspids, third > fourth; skull length > 18.5 mm.

Sorex bendirii(Marsh Shrew)

1513/1113 Five upper unicuspids, third < fourth; skull length > 19 mm; rostrum shallow and downcurved.

Sorex cinereus (Cinereus Shrew)

1513/1113 Five upper unicuspids, third > fourth; skull length >14.6 mm, <17.0 mm.

Sorex hoyi (Pigmy Shrew)

1513/1113 Three upper unicuspids easily visible laterally (third and fifth tiny).

Sorex merriami Merriam's Shrew)

1513/1113 Five upper unicuspids, third > fourth; first upper incisor lacking a medial tine.

Sorex monticolus (Montane Shrew)

1513/1113 Five upper unicuspids, third < fourth; skull length < 19 mm; medial side of upper incisor curved outward; upper unicuspids usually pigmented as far as cingulum; medial tine on upper incisor large and below pigment line.

Sorex palustris (Water Shrew)

1513/1113 Five upper unicuspids, third < fourth; skull length > 19mm; rostrum short and straight or downcurved only slightly in comparison to Sorex bendirii.

Sorex preblei (Preble's Shrew)

1513/ 1113 Five upper unicuspids, third > fourth; skull length < 14.6 mm.

Sorex rohweri(Olympic Shrew)

1513/1113 Five upper unicuspids, first two about equal in length, third and fourth similar in length or third < fourth; upper incisors diverge at about 45 degrees and their medial tines are above or near pigment line. Postero-lingual ridge absent from lower premolar 4. Patent foramina usually present in madibular rami. Pigment may extend to the lingual cingulum of the first four unicuspids as light bands or may be absent.

Sorex trowbridgii (Trowbridge's Shrew)

1513/1113 Five upper unicuspids, third < fourth; skull length < 19 mm; medial side of upper incisor curved outward; upper unicuspids usually not pigmented as far as cingulum.

Sorex tundrensis (Tundra Shrew)

1513/1113 Five upper unicuspids, third > fourth; skull length > 17.0 mm, < 18.5 mm.

Sorex vagrans (Vagrant Shrew)

1513/1113 Five upper unicuspids, third < fourth; skull length < 19 mm; medial side of upper incisor curved outward; upper unicuspids usually pigmented as far as cingulum; medial tine on upper incisor is small and is at or above pigment line.

Order CHIROPTERA (Bats)

Premaxillae unfused; molars dilambdodont.

Family Vespertilionidae (Vesper Bats)

Genus Myotis (Little Brown Bats)

Two upper incisors and six upper postcanine teeth per side, including two tiny premolars between the canine and third (large) premolar.

Myotis californicus (California Myotis)

2133/3133 Postorbital breadth < 3.4 mm; frontal slope abrupt.

Myotis ciliolabrum (Western Small-footed Myotis)

2133/3133 Postorbital breadth < 3.4 mm; frontal slope gradual.

Myotis evotis (Long-eared Myotis)

2133/3133 Postorbital breadth > 3.4 mm; postorbital width/upper toothrow length < 0.7; width between labial sides of last upper cheektooth < 6.2 mm; length of last four upper cheek-teeth > 4.2 mm; length of row of last seven teeth > 5.8 mm.

Myotis keenii (Keen's myotis)

2133/3133 Postorbital breadth > 3.4 mm; postorbital width/upper toothrow length < 0.7; width between facial sides of last upper cheektooth < 6.2 mm; length of last four upper cheek-teeth > 4.2 mm; length of row of last seven teeth < 5.8 mm; abrupt frontal slope.

Myotis lucifugus (Little Brown Bat)

2133/3133 Postorbital breadth > 3.4 mm; postorbital width/upper toothrow length >0.7; gradual frontal slope; skull length usually < 14.0 mm.

Myotis septentrionalis (Northern Myotis)

2133/3133 Postorbital breadth > 3.4 mm; postorbital width/upper toothrow length < 0.7; width between facial sides of last upper cheek-tooth < 6.2 mm; length of last four upper cheek-teeth > 4.2 mm; length of row of last seven teeth < 5.8 mm; gradual frontal slope.

Myotis thysanodes (Fringed Myotis)

2133/3133 Postorbital breadth > 3.4 mm; postorbital width/upper toothrow length < 0.7; width between facial sides of last upper cheek-tooth > 6.2 mm.

Myotis volans(Long-legged Myotis)

2133/3133 Postorbital breadth > 3.4 mm; postorbital width/upper toothrow length >0.7; occiput elevated.

Myotis yumanensis (Yuma Myotis)

2133/3133 Postorbital breadth > 3.4 mm; postorbital width/upper toothrow length >0.7; abrupt frontal slope; skull length usually < 14.0 mm.

Lasionycteris noctivagans (Silver-haired Bat)

2123/3133 Dorsal profile flattened; dorsal concavity on each side of rostrum; two upper incisors and five upper postcanine teeth per side; skull length < 18.0 mm; postorbital breadth > 4.0 mm.

Euderma maculatum (Spotted bat)

2123/3123 Frontal bulge; elongate cranium; supraorbital ridges; large bullae; distinct mid-zygomatic process; two upper incisors and five upper postcanine teeth per side; skull length > 18.0 mm.

Plecotus townsendii (Townsend's Big-eared Bat)

2123/3133 Curved braincase; large bullae; mandible shallow; two upper incisors and five upper postcanine teeth per side; skull length < 18.0 mm; postorbital breadth < 4.0 mm.

Eptesicus fuscus (Big Brown Bat)

2113/3123 Skull broad and flattened; mandible deep; two upper incisors and four upper postcanine teeth per side.

Genus Lasiurus (Hairy-tailed Bats)

A broad rugged skull with a short wide rostrum and wide palatal emargination; one upper incisor and five upper postcanine teeth per side.

Lasiurus blossevillii (Western Red Bat)

1123/3123 Skull length <15 mm.

Lasiurus cinereus (Hoary bat)

1123/3123 Skull length > 15 mm; third-to-last lower tooth single-rooted.

Antrozous pallidus (Pallid Bat)

1113/2123 One upper and two lower incisors per side; four upper postcanine teeth.

Order CARNIVORA (Dogs, Cats, Bears, etc.)

Prominent pair of canines in upper and lower jaw; mandibular condyle transverse.

Family Felidae (Cats)

Skull arched; rostrum short; bullae inflated; maximum 4 upper postcanine teeth; most cheek-teeth blade-like; alisphenoid canal absent.

Felis concolor (Mountain Lion)

3131/3121 Four upper postcanine teeth; last upper cheek-tooth minute.

Felis canadensis (Canada Lynx)

3121/3121 Three upper postcanine teeth; presphenoid usually wide; hypoglossal foramen usually separate from posterior lacerate foramen; angle of infraorbital canal usually projects dorsal to nasals; choanal border of palate circular.

Felis rufus (Bobcat)

3121/3121 Three upper postcanine teeth; presphenoid usually narrow; hypoglossal foramen usually confluent with posterior lacerate foramen; angle of infraorbital canal usually transects nasals.

Family Canidae (Dogs)

Rostrum long relative to cranial length; mastoid process < paroccipital process; toothrow flares posterolaterally; cheek-teeth blade-like; alisphenoid canal present.

Vulpes vulpes (Red Fox)

3142/3143 Postorbital width < interorbital width; postorbital processes concave on dorsal surface; incisors not strongly lobed.

Genus Canis (Wolves and Coyotes)

Postorbital width similar or > interorbital width; postorbital processes convex on dorsal surface.

Canis latrans (Coyote)

3142/3143 Rostrum narrow; upper canines often protrude beyond (apical) mental foramen (on anterior face of mandible); anteroposterior diameter of upper canine < 11 mm; spaces common between premolars; cusps on heel of lower carnassial more trenchant than in wolf and metaconid distinct; crown length of second lower premolar may be less than distance between second and third mental foramina.

Canis lupus (Gray Wolf)

3142/3143 Rostrum broad; upper canines generally don't protrude beyond (apical) mental foramen (on anterior face of mandible); anteroposterior diameter of upper canine > 11 mm; teeth wide and robust; mandible broad and deep; cusps on heel of lower carnassial less trenchant than in coyote and metaconid small or indistinct; crown length of second lower premolar often greater than distance between second and third mental foramina.

Family Ursidae (Bears)

Alisphenoid canal present; cheek-teeth bunodont; last upper cheek-tooth longest in row; mastoid large relative to paroccipital process; tooth row does not flare posterolaterally.

Ursus americanus (American Black Bear)

3142/3143 Last upper cheek-tooth generally broadest in mid-section, and length < 30mm.

Ursus arctos (Grizzly Bear)

3142/3143 Last upper cheek-tooth generally broadest rostrally and length > 31mm.

Family Otariidae (Sea Lions)

Two lower incisors per side; postcanine teeth nearly homodont; vacuity between frontal and palatine; alisphenoid canal present; postorbital processes present.

Callorhinus ursinus (Northern Fur-seal)

3142/2141 Rostrum very short, < 25% skull length; blunt profile; postorbital processes triangular; mandibular coronoid process bluntly pointed.

Eumetopias jubatus (Steller Sea Lion)

3141/2141 Disproportionate gap between last upper cheek-tooth and rest of tooth row, >five percent of skull length; postorbital process quadrate, far anterior; caudal margin of palate truncate.

Zalophus californianus (California Sea Lion)

3141-2/3141 Postorbital processes triangular; sagittal and occipital crests prominent.

Family Phocidae (Hair Seals)

Cheek-teeth nearly homodont; vacuity between frontal and palatine; alisphenoid canal absent; postorbital process absent; one or two lower incisors per side.

Phoca vitulina (Harbor Seal)

3141/2141 Premaxillae in contact with nasals; three upper and two lower incisors per side; most postcanine teeth double-rooted and lobed.

Mirounga angustirostris (Northern Elephant Seal)

2141/1141 Premaxillae not in contact with nasals; two upper and one lower incisor per side; postcanine teeth single-rooted and unlobed.

Family Procyonidae (Racoons)

3142/3142 Skull with arched profile; bullae inflated; 40 teeth; cheek-teeth bunodont; caudal border of mandibular coronoid process strongly concave.

Procyon lotor (Northern Raccoon)

Family Mustelidae (Weasels, Otters, etc,)

Skull dorsoventrally flattened; rostrum short; alisphenoid canal absent; palate extends well caudad of cheek teeth. maximum 38 teeth; bullae rarely inflated.

Lutra canadensis (Northern River otter)

3141/3132 Infraorbital foramen large; rostrum very short; five cheek teeth in each jaw.

Enhydra lutris (Sea Otter)

3131/2312 Posterior lacerate foramen large; rostrum very short; two lower incisors; four upper postcanine teeth, five lower.

Genus Martes (Martens)

Five upper postcanine teeth, six lower.

Martes americana (American Marten)

3141/3142 Second to last lower cheek-tooth <11 mm; total length < 90 mm; male may have mid-sagittal crest.

Martes pennanti (Fisher)

3141/3142 Second to last lower cheek-tooth >11 mm, total length usually >90 mm; male may have prominent mid-sagittal crest; fourth upper cheek-tooth may have show median rootlet on lateral side.

Genus Mustela (Weasels)

Four upper cheek teeth and five lower; mandibular coronoid process pointed and triangular.

Mustela erminea (Ermine)

3131/3132 Upper tooth row length < 20 mm in males and < 17.8 mm in females; postglenoid length > 47 percent condylobasal length;

Mustela frenata (Long-tailed Weasel)

3131/3132 Upper tooth row length < 20 mm in males and < 17.8 mm in females; postglenoid length < 47 percent condylobasal length.

Mustela nivalis (Least Weasel)

3131/3132 Upper tooth row length < 20 mm in males and < 17.8 mm in females; postglenoid length > 47 percent condylobasal length.

Neovison vison (American Mink)

3131/3132 Upper tooth row length >20 in males and > 17.8 in females.

Taxidea taxus (American Badger)

3131/3132 Skull triangular; bullae inflated; mandibular coronoid process angular, not smooth curve.

Gulo gulo (Wolverine)

3141/3142 Five upper and six lower postcanine teeth; massive rugged skull > 130 mm; zygoma plate-like, least width generally > 50 percent of gap in postorbital rim; postorbital process of zygoma pointed; maxillary flare over canine roots may result in maxillary notch when viewed from above.

Family Mephitidae (Skunks)

Skull dorsoventrally flattened; rostrum short; alisphenoid canal absent; bullae flattened; palate extends little beyond toothrows; caudal border of mandibular coronoid process straight or concave.

Spilogale putorius (Eastern Spotted Skunk)

3131/3132 Postorbital process present; first upper cheek-tooth prominent.

Mephitis mephitis (Striped Skunk)

3131/3132 Postorbital process lacking; first upper cheek-tooth tiny.

Order CETARTIODACTYLA: RUMINANTIA (Deer, Sheep, etc.)

Upper incisors absent; postcanine diastema; postorbital bar present; postcanine teeth selenodont.

Family Cervidae (Deer)

Vacuity between lacrimal and nasal; lacrimal orifice a double opening.

Cervus elaphus (Elk)

0133/3133 Post-narial aperture not divided by vomer; upper canines rounded; incisive foramina broad; premaxillae in contact with nasals; lacrimals as long or longer than orbits, nasals often extend as far posterior as antorbital margin. caudal margin of nasals usually V-shaped.

Alces alces (Moose)

0033/3133 Length of nasals < maxillary tooth row; palatine keels strongly curved medially and enclosing deep groove; mandibular ramus anterior to row of cheek-teeth longer than tooth row.

Genus Odocoileus (Mule and White-tailed Deer)

Post-narial aperture divided by vomer; upper canines absent; length of incisive foramina less than distance between incisive foramina and cheek-tooth rows. .

Odocoileus hemionus (Mule Deer)

0033/3133 Antorbital depression deep; premaxillae broad.

Odocoileus virginianus (White-tailed Deer)

0033/3133 Antorbital depression shallow; premaxillae narrow, length of incisive foramen measured from lateral suture to tip usually >4.5 x width measured at lateral suture.

Rangifer tarandus (Caribou)

0133/3133 Post-narial aperture divided by vomer; upper canines small and pointed; nasal process of premaxilla shows steep profile; antorbital rim caudal to last cheek-tooth

Family Bovidae (Sheep, Goats, etc.)

0033/3133 nasolacrimal suture present; horn cores present; lacrimal orifice single.

Genus Ovis

Lacrimal depression present; horn cores oval in cross-section and project caudally; premaxillae usually in contact with nasals; parietal region steeply arched caudo-ventrally.

Ovis canadensis (Bighorn Sheep)

0033/3133 Male horn cores blunt; horn sheath lacking prominent keel, horns brown.

Ovis dalli (Thinhorn Sheep)

0033/3133 Male horn cores pointed; male horn sheath keeled; horns tend to amber.

Oreamnos americanus (Mountain Goat)

0033/3133 Lacrimal depression absent; pointed horn cores circular in cross-section and project caudally; horns black.

Bison bison (American Bison)

0033/3133 Horn cores project laterally.

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References - Books and Series

Cowan, I. McT., and C.J. Guiget. 1965. The Mammals of British Columbia. 2nd ed. Victoria: British Columbia Provincial Museum.

Gilbert, M. 1980. Mammalian Osteology. Missouri Archaeological Society.

Glass, B. 1958. A Key to the Skulls of North American Mammals. Oklahoma State University.

Hall, E.R. 1981. The Mammals of North America. New York: John Wiley and Sons.

Hayssen, Virginia (Editor) Mammalian Species Online. American Society of Mammalogists.

Inglis, L.G. 1965. Mammals of the Pacific States. Stanford University Press.

Jones, C. et al. 1997. Revised Checklist of North American Mammals North of Mexico, 1997. Occasional Papers 173, Texas Tech University.

Jones, J.K. and R.W. Manning. 1992. Illustrated Key to Skulls of North American Land Mammals. Texas Tech University Press: Lubbock.

McKenna, M.C., and S.K. Bell. 1997. Classification of Mammals above the Species Level. New York: Columbia University Press.

Murphy, W.J. et al. 2001. Resolution of the early placental mammal radiation using Bayesian phylogenetics. Science, 294:2348-2351.

Nagorsen, D.W. 1996. Opossums, Shrews and Moles of British Columbia. Vancouver: UBC Press.

­Nagorsen, D.W. 1998. A Checklist of Mammals of British Columbia by Order and Family. Victoria: Royal British Columbia Museum.

Nagorsen, D. W. 2002. An Identification Manual to the Small Mammals of British Columbia. Province of British Columbia, Ministry of Sustainable Resource Management.

Nagorsen, D.W., and R.M. Brigham. 1993. Bats of British Columbia. Vancouver: UBC Press.

Roest, A.I. 1991. A Key-Guide to Mammal Skulls and Lower Jaws. Mad River Press: Eureka, CA.

Shackleton, D. 1999. Hoofed Mammals of British Columbia. Vancouver: UBC Press.

Wilson, D.E., and F.R. Cole. 2000. Common Names of Mammals of the World. Washington, DC: Smithsonian Institution Press.

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Lexicon of British Columbia Mammals

Copyright 2004, including code, script, and images. Peter Ommundsen.
Salt Spring Island, Canada

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