Leptobos
Leptobos is an extinct genus of large bovines, known from the Late Pliocene and Early Pleistocene of Eurasia, extending from the Iberian Peninsula and Britain to the Indian subcontent and northern China. It is widely posited to be the ancestor of bison.
Description
Species of Leptobos weighed on average, and have been described as being medium-sized bovines that had relatively slender limbs. The skulls of Leptobos species are relatively long and narrow and have proportionally elongate molar teeth Females lack horn cores. In males, the horn cores vary from being straight to somewhat curved, and generally diverge at an angle between 65° and 80° from each other. In a number of species, the horn cores are curved outward, upwards and forwards.Distribution and ecology
The genus is known from fossils found across the mid-latitudes of Eurasia, from Britain, the Nertherlands, and the Iberian Peninsula in the west, eastwards towards the northern Indian subcontinent and northern China. Species likely inhabited both open grasslands, forests and mixed forest-grassland environments. The dietary preference across the genus includes species that were browsers, grazers and mixed feeders. Damage to a lower jaw of Leptobos brevicornis from the Early Pleistocene of Longdan, Northern China indicates that this individual was predated upon by a big cat, likely Sivapanthera linxiaensis or Panthera palaeosinensis. Other likely potential predators include sabertooth cats.Taxonomy and evolution
The genus was first named in 1878 by Swiss paleontologist Ludwig Ruetimeyer, with the type species being Leptobos falconeri, named in the same publication based on remains found in the Siwalik hills of the Indian Subcontinent. The taxonomy of Leptobos is contentious. Authors have often accepted L. stenometopon–L. merlai–L. furtivus and L. etruscus–L. vallisarni as two distinct lineages within Leptobos. Duvernois in a 1992 publication alternatively suggested that Leptobos should be divided into two subgenera based on the shape of their horn cores: Leptobos containing the species L. elatus and L. furtivus and Smertiobos, containing L. etruscus and potentially L. bravardi, though this scheme is controversial has not been accepted by all authors.Species
- Leptobos brevicornis Hu and Qi, 1978
- Leptobos crassus Jia and Wang, 1978
- Leptobos falconeri Ruetimeyer, 1878
- Leptobos stenometopon Sismonda, 1846
- Leptobos merlai DeGiuli, 1987
- Leptobos furtivus
- Leptobos etruscus Falconer, 1859
- Leptobos vallisarni Merla, 1949