Chiyoumeryx, Mennecart & Aiglstorfer & Li & Li & Wang, 2021

Mennecart, Bastien, Aiglstorfer, Manuela, Li, Yikun, Li, Chunxiao & Wang, ShiQi, 2021, Ruminants reveal Eocene Asiatic palaeobiogeographical provinces as the origin of diachronous mammalian Oligocene dispersals into Europe, Scientific Reports 1, pp. 1-12 : 4-5

Chiyoumeryx nov. gen.

ZooBank LSID. urn:lsid:zoobank.org:act:464C46E0-5A69-4AC1-A9DD-8A7DF76D5CC0.

Etymology. Chiyou is a tribe leader of the ancient China, about 5–4 k years ago. Chiyou’s tribe was believed to be in relation with the peoples in southern China; - meryx means ruminant in Greek.

Diagnosis. Chiyoumeryx nov. gen. differs from Zhailimeryx and Krabimeryx notably by the absence of the entoconidian groove. Te lower teeth are more laterally compressed in Chiyoumeryx nov. gen. and the metaconid is linguo-labiallly more central than in the two other genera. Te posthypoconulidcristid in the lower molars of Chiyoumeryx nov. gen. is longer than in Krabimeryx and its p4 is posteriorly extended, while this part is reduced in Krabimeryx . Chiyoumeryx nov. gen. differs from Lophiomeryx by the shape of the mandible. In Chiyoumeryx nov. gen. there is no diastema between p1 and p2 and the diastema between c and p1 is extremely reduced. Te outline of the mandible in occlusal view is relatively straight in this species. Lophiomeryx possesses a long diastema between c and p1 and a small one between p1 and p2, as well as a regularly curved occlusal outline of the corpus. Te lower premolars of Chiyoumeryx nov. gen. are laterally compressed giving a more elongated aspect to these teeth than in Lophiomeryx . Te trigonid is smaller than the talonid in m1 and m2

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in Chiyoumeryx nov. gen. and the preprotocristid terminates centrally and does not reach the lingual side. In Lophiomeryx the trigonid and talonid are of similar size and the preprotocristid is longer and reaches the lingual side. Moreover, in Chiyoumeryx nov. gen., the posthypoconulidcristid is longer than in Lophiomeryx . Te shape of the P4 in Chiyoumeryx nov. gen. differs from the one in Lophiomeryx : the posterolingual crista does not meet the posterolabial crista.

Type species. Chiyoumeryx nov. gen. shinaoensis (Miao, 198220).

Included species. Chiyoumeryx nov. gen. flavimperatoris nov. sp.;? Chiyoumeryx nov. gen. turgaicus (Flerow 193838).