Hyaenodon

Taxobox
name = "Hyaenodon"


image_width = 220px
image_caption = Skull of "Hyaenodon cayluxi", Muséum national d'Histoire naturelle, Paris.
fossil_range = Late Eocene to Early Miocene
regnum = Animalia
phylum = Chordata
classis = Mammalia
ordo = Creodonta
familia = Hyaenodontidae
genus = "Hyaenodon"
genus_authority = Leidy, 1869
subdivision_ranks = Species [http://www.fmnh.helsinki.fi/users/haaramo/Metazoa/Deuterostoma/Chordata/Synapsida/Eutheria/Creodonta/Hyeanodontinae.htm Mikko's Phylogeny Archive — Hyaenodonts] ]
subdivision = "H. bavaricus" "H. brevirostris" "H. chunkhtensis" "H. crucians" "H. eminus" "H. exicuus" "H. gigas" "H. horridus" "H. incertus" "H. leptorhynchus" "H. megaloides" "H. microdon" "H. milloquensis" "H. mongoliensis" "H. montanus" "H. mustelinus" "H. pervagus" "H. raineyi" "H. venturae" "H. vetus" "H. weilini" "H. yuanchensis"

"Hyaenodon" ("hyaena-toothed") is an extinct genus of Hyaenodonts, a group of Creodonts. Some species of this genus were amongst the largest terrestrial carnivorous mammals of their time, others were only of the size of a marten. "Hyaenodon" was one of the latest genera of the Hyaenodonts and is known from the Late Eocene to Early Miocene. Remains of many species are known from North America, Europe, Asia and Africa (In 1993 42 species were distinguished)Wang, Xiaoming, Qiu, Zhanxiang, and Wang, Banyue, 2005. Hyaenodonts and Carnivorans from the Early Oligocene to Early Miocene of Xianshuihe Formation, Lanzhou Basin, Gansu Province, China, Palaeontologia Electronica Vol. 8, Issue 1; 6A: 14p, [http://palaeo-electronica.org/paleo/2005_1/wang6/issue1_05.htm online] ] .

Range and species

In North America the last "Hyaenodon" disappeared along with species like "H. brevirostris" in the late Oligocene. In Europe they had already vanished earlier in the Oligocene. From the Miocene in Africa there are three species ("H. andrewsi", "H. matthewi" und "H. pilgrimi") known, but none of these reached the dimensions of Asian species like "H. gigas" and "H. weilini"Wang, Xiaoming, Qiu, Zhanxiang, and Wang, Banyue, 2005. Hyaenodonts and Carnivorans from the Early Oligocene to Early Miocene of Xianshuihe Formation, Lanzhou Basin, Gansu Province, China, Palaeontologia Electronica Vol. 8, Issue 1; 6A: 14p http://palaeo-electronica.org/paleo/2005_1/wang6/issue1_05.htm]

Description

Typical of early carnivorous mammals, they had very massive skulls but only small brains. It had a long skull with a narrow snout - much larger in relation to the length of the skull than in canine carnivores, for instance. Its neck was shorter than its skull, while its body was long and robust and terminated in a long tail.

The average weight of adult or subadult "H. horridus", the largest North American species, is estimated to about 40 kg and may not have exceeded 60 kg. "H. gigas", the largest "Hyaenodon" species was much larger. "H. crucians" from the early Oligocene of North America is estimated to only 10 bis 25 kg. "H. microdon" and "H. mustelinus" from the late Eocene of North America were even smaller and weighed probably about 5 kg [Naoko Egi (2001) Body Mass Estimates in Extinct Mammals from Limb Bone Dimensions: the Case of North American Hyaenodontids _Palaeontology 44 (3) , 497–528 doi:10.1111/1475-4983.00189] .
[
Heinrich Harder, c.1920]

References

*Haines, Tim & Chambers, Paul. (2006) The Complete Guide to Prehistoric Life. Canada: Firefly Books Ltd.

ee also

* List of apex predators