|The Mammals of Texas
This Order is characterized by either two or four (usually) hoofed toes on each foot, with the exception of the peccary which has four toes on each forefoot, but only three on the hind. The American forms of the order are readily divisible into two groups on the basis of structure of the teeth, presence or absence of horns, and structure of the stomach and feet. The pig group has crushing cheek teeth, upper incisors, a simple stomach, no horns, four hoofed toes, and includes the peccaries. The cow group has rasping cheek teeth, no upper incisors, two or four hoofed toes on each foot, complex stomach, and horns or antlers in most species. It includes the deer, elk and allies; cows and allies; and the pronghorn.
Seven species of artiodactyls are native to Texas although three of these — the mountain sheep, bison, and American elk have been extirpated. Recent reintroductions of these big game animals account for their current presence in the state. In addition, 123 species of ungulates not native to Texas have been imported into the state since 1930. For the most part, these "exotic" animals have been confined on private ranches; however, seven species have escaped, reproduced, and now exist in parts of Texas as free-ranging, feral populations that comprise a part of the local fauna. As the possibility of sighting, or for finding the remains of, these unusual animals mounts yearly in Texas, accounts for the most common exotics have been included in this revision. Accounts of exotics are adapted from the book, Texotics, by Elizabeth Cary Mungall and William J. Sheffield, Texas A&M University Press, College Station, Texas.
KEY TO THE EVEN-TOED UNGULATES OF TEXAS
Medium size; body form stocky and barrel-like; head long and pointed with very short neck; legs short; snout with terminal nasal disc (pig-like); upper incisors present: 2
Large size; body form slender or cowlike; head with well-developed neck; legs long; snout never piglike; upper incisors absent: 3
Sparsely covered with coarse bristly hair; some individuals with a scantily haired dorsal mane; tail approximately 300 mm in length; each foot with four toes (the middle two are flattened and have hooves, whereas the lateral toes are higher up on the limb and do not normally touch the ground); adult weight up to 350 kg: Sus scrofa (feral pig).
Pelage thick, bristly; well-developed dorsal mane of long, stiff hairs extending along back from crown to rump; tail length 15-55 mm; front feet with four toes, hind feet with three toes; adult weight 14-30 kg: Pecari tajacu (collared peccary).
Two toes on each foot; males with prominent, forked horns; horn sheaths shed annually; females usually with smaller horns that do not shed: Antilocapra americana (pronghorn).
Four toes on each foot; horns or antlers present: 4
4. Males (rarely females) with branching antlers that are shed annually. Family Cervidae: 5
Males and females (except in nilgai) with backward curving, unbranched horns no part of which is shed: 10
5. Adults with reddish, brown, or dark brown pelage generally heavily speckled with white spots: 6
Adults with unspotted pelage (juveniles often spotted): 8
6. Antlers flattened, palmate, and with numerous points: Dama dama (fallow deer).
Antlers not palmate: 7
7. Antlers 75-100 cm in length along outer curve; normally with only three tines; brow tines project outward to form a nearly 90° angle with main beam: Axic axis (axis deer).
Antlers 28-48 cm in length; normally with 3 or 4 tines branching from main beam: Cervus nippon (sika deer).
8. Large (cow size); conspicuous white or cream colored rump patch; upper canine teeth normally present: Cervus elaphus (wapiti or elk).
Medium size; white rump patch reduced; upper canine teeth absent: 9
9. Antlers usually equally branched (dichotomous) and normally with five or more tines per side, including brow tine; metatarsal gland on hind leg narrow and elongate, 75-125 mm long, and situated above mid-point of shank; tail narrow at base: Odocoileus hemionus (mule deer).
Antlers with all tines branching off the main beam in a nearly vertical position; metatarsal gland on hind leg nearly circular and about ≤ 25 mm in diameter; tail broad at base, when alarmed held erect to show conspicuous white "flag." Odocoileus virginianus (white-tailed deer).
10. Large size; body form stocky and compact ("cowlike"); conspicuous hump dorsally over shoulder: Bos bison (bison).
Medium size; body form slender and "deer-like"; dorsal hump absent: 11
11. Horns short and smooth; or tall, marked with strong transverse wrinkles, and twisted in a "corkscrew" pattern; but in all cases rise straight above head in a V-shaped pattern: 12
Horns massive (in males), curve out and back from head and then inward to form a "curl" at side of head; females with smaller horns that do not curl, but horns in both sexes marked with strong transverse wrinkles: 13
12. Large size; height at shoulder greater than height at rump, giving a backward sloping appearance to profile; males with short, straight horns seldom exceeding 18 cm in length; coloration uniform light brown to iron gray: Boselaphus tragocamelus (nilgai).
Medium size; height at shoulder equal to height at rump, no backward slope to profile; males with long, twisted horns up to 79 cm in length; coloration tan to black dorsally with striking white eye rings, chin, chest, belly, and inner legs: Antilope cervicapra (blackbuck).
13. Conspicuous ventral mane of long hairs hanging from throat and chest; coloration light rufous-brown; whitish rump patch small and inconspicuous: Ammotragus lervia (Barbary sheep).
Ventral mane absent; coloration light brown to gray; white rump patch large and prominent: Ovis canadensis (Bighorn sheep).
Family Suidae (pigs)
Feral Pig, Sus scrofa*
Family Tayassuidae (peccaries)
Collared Peccary, Pecari tajacu
Family Cervidae (cervids)
Axis Deer (Chital), Cervus axis*, now Axis axis*
Fallow Deer, Cervus dama*, now Dama dama*
Wapiti or Elk, Cervus elaphus
Sika Deer, Cervus nippon*
Mule Deer, Odocoileus hemionus
White-tailed Deer, Odocoileus virginianus
Family Antilocapridae (pronghorn)
Pronghorn, Antilocapra americana
Family Bovidae (bovids)
Nilgai, Boselaphus tragocamelus*
Bison, Bos bison
Bighorn Sheep, Ovis canadensis
Mouflon, Ovis aries* (formerly O. musimon) the wild ancestor of domestic sheep
Barbary Sheep, Ammotragus lervia*
Blackbuck, Antilope cervicapra*