UCLA

Well adapted to extremely cold winters (hypothermia) and low oxygen (hypoxia), the Tibetan antelope (or chiru), Pantholops hodgsonii Abel, is an iconic species in the Tibetan Plateau. Its extinct relative, Qurliqnoria Bohlin, represents the earliest endemic Tibetan mammal going back to the late Miocene, suggesting a long process of adaptations within Tibetan Plateau for ~ 10 million years. We reexamine holotype materials of Q. hundesiensis (Lydekker) from the British Museum, originally discovered by British explorers in the Himalayas in the early 1800s, and new materials recently discovered in the Pliocene strata of Zanda Basin, southwestern Tibet. We refer additional horncore and dental materials from the Kunlun Pass Basin at 4,700–4,900 m asl, and leverage these new data to place Q. hundesiensis within modern biostratigraphic and paleoenvironmental frameworks. Although Qurliqnoria remains the best candidate of a distant sister-group of living Pantholops, the Pliocene representatives offer no sign of transitions to living chiru. We infer that the Qurliqnoria lineage has persisted throughout late Miocene and Pliocene of the Tibetan Plateau in a chronospecies succession, i.e., Q. cheni to Q. hundesiensis. The Pliocene Qurliqnoria probably did not directly give rise to Pantholops, suggesting that a direct ancestor of Pantholops is yet to be found. We discuss the paleoenvironmental and paleoelevational implications of the new Qurliqnoria materials and analysis for Tibetan Plateau faunal evolution.