This animal would look much like other chalicotheriid species: an odd-looking herbivore with long clawedforelimbs and stouter weight-bearing hindlimbs.
Chalicotherium, like many members of Perissodactyla, was adapted to browsing, though the chalicotheres were uniquely adapted to do so among ungulates. Its arms were long and heavily clawed, allowing them to walk on their knuckles only. The arms were used to reach for the branches of large trees and bring them close to its long head to strip them clean of leaves. The horse-like head itself shows adaptation to a diet of soft vegetation, since, as the animal reached sexual maturity, the incisors and upper canines were shed, suggesting that its muscular lips and the resulting gum pads were enough to crop fodder which was then processed by squarish, low-crowned molars.
Callosities on the ischium imply that these animals would sit on their haunches for extended periods of time, probably while feeding. Pad-supporting bony growth on the dorsal side of the manual phalanges is interpreted as evidence of knuckle-walking, which would probably be useful to avoid wearing down the claws, preserving them for use either as a forage-collecting rake or as a formidable defensive weapon, or both.
The type specimens for Chalicotherium goldfussi were found in the Upper Miocene strata of the Dinotherien-sande beds near Eppelsheim, in the Grand Duchy of Hesse, Germany. Johann Jakob Kaup, when describing this new animal in 1833, found the teeth to be pebble-like and named the creature accordingly. Later on, limbs found in strata located at Sansan in the department of Gers, Southwestern France, were first described as Macrotherium by Édouard Lartet in 1837. Further study of these fossil remains and subsequent finds by Filhol warranted a referral of the material described as Macrotherium to Chalicotherium.[2]
Referral history for each species is detailed in the species list below along with morphological and geographical data where available.
Species
Valid:
Chalicotherium goldfussi J. J. Kaup, 1833.
The type species, it was found in Upper Miocene beds located in Germany. It weighed around 1500 kg and was 2.6 m high at the shoulder.[citation needed]
Chalicotherium brevirostris Colbert, 1934
First described as Macrotherium brevirostris, this species hails from the Upper Miocene Tung Gur Formation, Inner Mongolia, China.
Invalid:
Chalicotherium antiquum J. J. Kaup, 1833.
Found at the same locality as the type species, it was later found wanting of diagnostic features and sunk into the type species.
Misassigned specimens:
Chalicotherium cf. C. brevirostris Wang et al., 2001.
^Anquetin,J.,Antoine,P.-O.,Tassy,P.,2007.Middle Miocene Chalicotheriinae(Mammalia, Perissodactyla)from France, with a discussion on chalicotheriine phylogeny. Zoological Journal of the Linnean Society 151, 577–608.
Further reading
Grande Enciclopédia Portuguesa e Brasileira, vol. 5. (1936-1960). Editorial Enciclopédia, Lda, Lisbon.
Butler, P. M., 1978: Chalicotheriidae. 368–370. in Maglio, V. J. & Cooke, H. B. S., (eds.) 1978: Evolution of African mammals. – Harvard University Press, Cambridge, Massachusetts & London, England, 1978, xiv-641
Carroll, R. L., 1988: Vertebrate paleontology and evolution. – W. H. Freeman and company, New York, 1988, 698.
Carroll, R. L., 1988: Appendix. 594–648. in Carroll, R. L., 1988: Vertebrate paleontology and evolution. – W. H. Freeman and company, New York, 1988, 698.
Coombs, M. C., 1989: Interrelationships and diversity in the Chalicotheriidae. 438–457. in Prothero, D. R. & Schoch, R. M., (eds.) 1989: The Evolution of Perissodactyls. – Oxford University Press, New York, New York & Oxford, England, 1989, ix-537
Coombs, M. C., Hunt, Jr, R. M., Stepleton, E., Albright III, L. B. & Fremd, T. J., 2001: Stratigraphy, chronology, biogeography, and taxonomy of Early Miocene small chalicotheres in North America. – Journal of Vertebrate Paleontology: Vol. 21, #3, pp. 607–620
Geraads, D., Spassov, N. & Kovachev, D., 2001: New Chalicotheriidae (Perissodactyla, Mammalia) from the Late Miocene of Bulgaria. – Journal of Vertebrate Paleontology: Vol. 21, #3, pp. 569–606
Hooker, J. J. & Dashzeveg, D., 2004: The origin of chalicotheres (Perissodactyla, Mammalia) – Palaeontology: Vol. 47, #6, pp. 1363–1386
Lucas, S. G. & Schoch, R. M., 1989: Taxonomy and biochronology of Eomoropus and Grangeria, Eocene chalicotheres from the western United States and China. 422–437. in Prothero, D. R. & Schoch, R. M., (eds.) 1989: The Evolution of Perissodactyls. – Oxford University Press, New York, New York & Oxford, England, 1989, ix-537
McKenna, M. C. & Bell, S. K., (eds.) 1997: Classification of mammals – above the species level. – Columbia University Press, New York, 1997, xii-631
Prothero, D. R. & Schoch, R. M., 1989: Classification of the Perissodactyla. 530–537. in Prothero, D. R. & Schoch, R. M., (eds.) 1989: The Evolution of Perissodactyls. – Oxford University Press, New York, New York & Oxford, England, 1989, ix-537
Remy, J.-A., Jaeger, J.-J., Chaimanee, Y., Soe, U. A. N., Marivaux, L., Sudre, J., Tun, S. T., Marandat, B. & Dewaele, E., 2005: A new chalicothere from the Pondaung Formation (late Middle Eocene) of Myanmar. – Comptes Rendus de l'Académie des Sciencies, Paris: Palevol: Vol. 4, pp. 341–349
The America Heritage Dictionary of English Language. 2004, 2000. Houghton Mifflin Company.
Wang, Xiaoming; Wang, Banyue (2001): New material of Chalicotherium from the Tsaidam Basin in the northern Qinghai-Tibetan Plateau, China. Paläontologische Zeitschrift, Vol 75, Fascicle 2. Pages 219–226.
