Leptauchenia

Leptauchenia
Leptauchenia
Temporal range: Late Oligocene
Leptauchenia decora skull
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Artiodactyla
Family: †Merycoidodontidae
Subfamily: Leptaucheniinae
Tribe: Leptaucheniini
Genus: Leptauchenia
Leidy, 1856
Type species
Leptauchenia decora
Leidy, 1856
Species

see text

Synonyms
  • Brachymeryx
  • Cyclopidius
  • Hadroleptauchenia
  • Pithecistes
  • Pseudocyclopidius

Leptauchenia is an extinct goat-like genus of terrestrial herbivore belonging to the oreodont family Merycoidodontidae, and the type genus of the tribe Leptaucheniini. The genus was endemic to North America during the Late Oligocene (33.9—16.3 mya) and lived for approximately 17.6 million years.[1]

Contents

Morphology

Artist's reconstruction of Leptauchenia decora

Because the eyes and nostrils were placed high on the head, it was long assumed that Leptauchenia was an aquatic, or semi-aquatic animal. However, because their fossils have never been found in floodplain deposits or river channels, and their abundance in fossil sand dunes, Donald Prothero suggests that they were desert-dwelling animals.[2] According to Prothero's interpretation, the high-placed eyes and nostrils served to filter out sand while burrowing.

A single specimen was examined by M. Mendoza for body mass and estimated to have a weight of 39.3 kilograms (87 lb). [3]

Fossil distribution

Skeletons of Leptauchenia have been found by the thousands and in greater numbers than the related genus Sespia, it is often quoted as being the most numerous mammal in North America during the Late Oligocene.[4] It had high-crowned, hypsodont teeth which were used to chew gritty vegetation.

Species

  • L. brevifacies (syn. Pithecistes decedens)
  • L. decora (type species) (syn. Hadroleptauchenia primitiva, Leptauchenia harveyi, Pithecistes breviceps, Pithecistes facies, Pithecistes tanneri, Pseudocyclopidius frankforteri)
  • L. eiselyi
  • L. major (syn. Brachymeryx feliceps, Cyclopidius emydinus, Cyclopidius incisivus, Cyclopidius lullianus, Cyclopidius simus, Hadroleptauchenia extrema, Hadroleptauchenia shanafeltae, L. densa, L. margeryae, L. martini, L. parasimus, Pithecistes altageringensis, Pithecistes copei)
  • L. orellaensis

References

  1. ^ PaleoBiology Database: Leptauchenia, basic info
  2. ^ Prothero, D. R., and F. Sanchez. 2005. Review of the leptauchenine oreodonts (Mammalia: Artiodacttyla). New Mexico Museum of Natural History and Science Bulletin.
  3. ^ M. Mendoza, C. M. Janis, and P. Palmqvist. 2006. Estimating the body mass of extinct ungulates: a study on the use of multiple regression. Journal of Zoology
  4. ^ Prothero, D.R. (2006). After the Dinosaurs: The Age of Mammals. Indiana University Press. ISBN 0253347335.