''Tylocephalonyx'' (Greek: "knob" (tylos), "head" (kephalos), "claw/hoof" (onyx)) is an
extinct
Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...
chalicothere
Chalicotheres (from Greek '' chalix'', "gravel" and '' therion'', "beast") are an extinct clade of herbivorous, odd-toed ungulate (perissodactyl) mammals that lived in North America, Eurasia, and Africa from the Middle Eocene until the Early Plei ...
from the
Miocene of
North America
North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...
.
Description
''Tylocephalonyx'' specimens are notable for a dome-shaped skull, a feature found in some other schizotheriine chalicotheres but most developed in this genus. Adequate fossil material is lacking to tell whether both sexes had domed heads, but sexual dimorphism was common in the group. ''Tylocephalonyx'' may have used its "dome" in the same way as the
pachycephalosaurs, though there is no clear evidence to link either
pachycephalosaurs nor ''Tylocephalonyx'' to using their domes to crash together in high-impact head-to-head contests, as in modern
bighorn sheep. Such contests require special cranial adaptations to protect the brain and cervical spine, not shown in chalicotheres. The dome of ''Tylocephalonyx'' may have been used for visual display or in butting or head-to-body battering contests.
''Tylocephalonyx'' is a perrisodactyl, related to the modern
horse,
rhino, and
tapir and to the extinct
brontotheres.
See also
*''
Moropus''
*''
Chalicotherium''
*''
Ancylotherium''
*''
Kalimantsia
''Kalimantsia'' is an extinct chalicothere from the Miocene of Bulgaria, Europe. It contains one species, ''K. bulgarica''.
Description
''Kalimantsia'' is named for the area in which it was discovered in 2001 by Geraads, Spassov, and Kovachev. ...
''
References
Sources
*''National Geographic Prehistoric Mammals'' (
National Geographic
''National Geographic'' (formerly the ''National Geographic Magazine'', sometimes branded as NAT GEO) is a popular American monthly magazine published by National Geographic Partners. Known for its photojournalism, it is one of the most widely ...
) by Alan Turner
*''After the Dinosaurs: The Age of Mammals'' (Life of the Past) by Donald R. Prothero
*''Classification of Mammals'' by Malcolm C. McKenna and Susan K. Bell
*''Late Cretaceous and Cenozoic Mammals of North America: Biostratigraphy and Geochronology'' by Michael O. Woodburne
*''Colbert's Evolution of the Vertebrates: A History of the Backboned Animals Through Time'' by Edwin H. Colbert, Michael Morales, and Eli C. Minkoff
*
Chalicotheres
Miocene odd-toed ungulates
Miocene mammals of North America
Fossil taxa described in 1979
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