ORDER ARTIODACTYLA

EVEN-TOED UNGULATES

Worldwide, this order contains 10 families and over 240 species.  Members of this order are 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 foot.  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, large upper incisors, a simple stomach, no horns, and four hoofed toes.  This group is composed of two families -- the pigs (Suidae) and peccaries (Tayassuidae).  The "cow group" has rasping cheek teeth, no upper incisors, two or four hoofed toes on each foot, a complex stomach, and horns or antlers in most species.  This group includes the deer, elk, and allies (Cervidae); cows and allies (Bovidae); and the pronghorn (Antilocapridae). 

Seven species of artiodactyls are native to Texas, although three of these (the bighorn sheep, bison, and elk) were extirpated.  Recent reintroductions of the big-game animals, by private individuals and captive breeding programs sponsored by the Texas Parks and Wildlife Department (TPWD), account for their current presence in the state.  In addition, at least 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, 11 species have escaped, reproduced, and now exist in parts of Texas as free-ranging, feral populations that constitute a part of the local fauna.  As the possibility of sighting or finding the remains of these unusual animals increases yearly in Texas, accounts for the most common exotics have been included in this revision.  Accounts of exotics are adapted from the book Exotics on the Open Range, by Elizabeth Cary Mungall and William J. Sheffield (Texas A&M University Press, College Station, 1994).  At least three exotics, the scimitar-horned oryx, addax antelope, and dama gazelle, are native to North Africa where they are considered endangered.

 

KEY TO THE EVEN-TOED UNGULATES OF TEXAS

1. Medium size; body form stocky and barrel-like; head long and pointed with very short neck; legs short; snout with terminal nasal disk (pig-like); upper incisors present .......................................................................... 2

Large size; body form slender or cow-like; head with well-developed neck; legs long; snout never pig-like; upper incisors absent ............................ 3

2. 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, while 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 hog).

Pelage thick and 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).

3. Two toes on each foot; males with prominent, forked horns; horn sheaths shed annually; females usually with smaller horns that do not shed annually.  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.  Family Bovidae .................................... 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 nearly 90-degree angle with main beam.  Axis axis (axis deer).

Antlers 28-48 cm in length; normally with three or four tines branching from main beam.  Cervus nippon (sika deer).

8. Large size (cow size); conspicuous white or cream-colored rump patch; upper canine teeth normally present.  Cervus canadensis (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 midpoint 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 <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 (cow-like); conspicuous hump dorsally over shoulder.  Bos bison (American 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 corkscrew pattern; but in all cases rising straight above head in a V-shaped pattern ........................................................................... 12

Horns massive (in males), curving out and back from head and then inward to form a curl at side of head; females with smaller horns that do not curl; 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 or aoudad).

Ventral mane absent; coloration light brown to gray; white rump patch large and prominent.  Ovis canadensis (bighorn sheep).

 

Family Antilocapridae

Pronghorn

The pronghorn is the only member of this family.  It is endemic to North America and represents the only surviving member of a group of about a dozen species that occurred during the Pleistocene of North America.  Pronghorns are adapted to open country, where they use their speed and endurance to escape predators. 

 

Family Bovidae

Cattle, Antelope, Sheep, Goats, and African Exotics

The bovids are the largest group of artiodactyls, with 143 species worldwide.  Five species occur in North America, only two of which are native to Texas.  However, several exotic species have been introduced to the state from Europe, Asia, and Africa.  Accounts are provided for the two native species.  Additional accounts are provided for introduced species that are free-ranging and common in parts of the state.

 

Family Cervidae

Deer and Allies

The family Cervidae comprises 51 species and 19 genera worldwide.  Three species (white-tailed and mule deer and elk) are native to Texas.  Several species native to Europe, Asia, and Africa have been introduced as game animals, however, and at least three species are free-ranging and populous enough to be considered a permanent component of the state's fauna. 

 

Family Tayassuidae

Peccaries

This family comprises three genera, each with only a single species.  All are found in South America; only the collared peccary ranges northward to the United States.  The peccaries have a pig-like body form, but the legs are long and slim and the hooves are small.  They inhabit grasslands, desert scrub communities, and arid woodlands.  These are highly social and territorial animals.  They are omnivorous but feed primarily on fruits, seeds, roots, tubers, and cacti. 

 

From The Mammals of Texas, Seventh Edition by David J. Schmidly and Robert D. Bradley, copyright © 1994, 2004, 2016.  Courtesy of the University of Texas Press.