Xenorhinotherium

Xenorhinotherium is an extinct genus of macraucheniine macraucheniids, closely related to Macrauchenia of Patagonia. The type species is X. bahiense.

Taxonomy
Some authors consider the genus Xenorhinotherium a synonym of Macrauchenia, while all others consider it a distinct genus. The name Xenorhinotherium means "Strange-Nosed Beast" and bahiense refers to the Brazilian state of Bahia, where the first fossils were found.

Xenorhinotherium was a rather derived representative of the Macraucheniidae, a group of litopterns with camel-like appearances. Probably derived from lower Miocene forms such as Cramauchenia and Theosodon, this animal probably closely related to the large macraucheniids of the Pliocene and Pleistocene, such as Macrauchenia and Windhausenia.

Below is a phylogenetic tree of the Macraucheniidae, based on the work of McGrath et al. 2018, showing the position of Xenorhinotherium.

Characteristics
X. bahiense was a megafaunal herbivore that probably looked very much like Macrauchenia, weighing about 940 kg. In life, X. bahiense would have vaguely resembled a tall, humpless camel with three toes on each foot and either a saiga-like proboscis or a moose-like nose. Pictographs from the Serranía de La Lindosa rock formation of Guaviare, Colombia, show what might possibly be Xenorhinotherium with three toes and a trunk, though the claims are highly controversial, and it is uncertain whether they even date to the last Ice Age.

Paired δ13C and δ18O measurements from fossils in the Brazilian Intertropical Region indicate that X. bahiense was primarily a browser.

Distribution
Fossils of Xenorhinotherium, dating from the Late Pleistocene to the Early Holocene, have been found in the states of Bahia, the Jandaíra Formation of Rio Grande do Norte, and Minas Gerais in modern Brazil, and also in Venezuela, in the localities of Muaco, Taima-Taima and Cuenca del Lago.

Though not known from other countries, computer modelling suggests that the habitat in the western Andean slopes of Colombia, Ecuador, and Peru would have been suitable for this animal, particularly in areas that have not been extensively excavated yet.