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''Tetrameryx'' is an extinct 
One member of the genus, ''T. shuleri'', survived until about 12,000 years ago, and was present when Paleo-Indians reached North America. Although approximately the same size as the living pronghorn, the limb bones are somewhat more robust, suggesting that its running speed was slower than living pronghorn.
genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...
of the North American artiodactyl
The even-toed ungulates (Artiodactyla , ) are ungulates—hoofed animals—which bear weight equally on two (an even number) of their five toes: the third and fourth. The other three toes are either present, absent, vestigial, or pointing poster ...
family Antilocapridae, known from Mexico, the western United States, and Saskatchewan
Saskatchewan ( ; ) is a province in western Canada, bordered on the west by Alberta, on the north by the Northwest Territories, on the east by Manitoba, to the northeast by Nunavut, and on the south by the U.S. states of Montana and North Dak ...
. The name means "four ornedruminant", referring to the division of each horn near its base into two prongs; in ''T. shuleri'', the rear prong is much longer.
One member of the genus, ''T. shuleri'', survived until about 12,000 years ago, and was present when Paleo-Indians reached North America. Although approximately the same size as the living pronghorn, the limb bones are somewhat more robust, suggesting that its running speed was slower than living pronghorn.
References
Prehistoric pronghorns Prehistoric even-toed ungulate genera Extinct mammals of North America Taxa named by Richard Swann Lull Fossil taxa described in 1921 Pleistocene mammals of North America {{paleo-eventoedungulate-stub