作者：武云飞 陈宜瑜

摘要：In this paper a new genus and species of the Late Tertiary Cyprinid fish is described, based upon fossils collected from Lunbola basin of north Xizang in 1976-1978. The fossils were embedded in the gray-green shale which is found in the second zone of the Dingqing formation of the Tertiary sediments. According to data of the fossil spero-pollen analysis, the geological age of  the fish-bearing sediment is Late Miocene or Early Pliocene.
    Plesioschizothorax macrocephalus Wu et Chen, gen. et sp. nov.
    Type: A nearly complete individual, No. 78007, kept in Qinghai Institute of Biology, Xining.
    Paratype: Three nearly complete individuals with a number of imperfect fragments, No.78006, 78008, 78009, etc.
    Diagnosis: Fish of moderate size. D. 4,8-9;A. 3,5;P. 1,16;V. 1,8. Depth of body contained in standard length 4.7(4.3-5.7)，length of head 3.3 (3.1-3.4)，length of caudal peducle 8.3(7.8-9.0), its depth 11.3(11.0-12.0). Body elongate and compressed. Mouth terminal, arched. The dentary elongate, lower jaw without horny structure. The skull provided with preethmoid, without quadrate-metapterygoid foramen. Pharyngeal teeth in 3 row, 2,3,5,-5,3,2, conical, pointed and hooked at tip. ,
  Vertebrae 4+42-44; the 2nd, and 3rd. centra fused, transverse processes of the 4th vertebra pointed at tip. The dorsal branch of the cleithrum provided with an anterior lamina. The anterior forked portion of the pelvic bone deep. The simple dorsal ray slender and weak, without serrature.  Origin of ventral beneath the 4th branched ray of the dorsal. Anal short. Caudal forked.
    Remarks: From the characters described above, this new genus is closely related to Schizothorax, Barbus, Varicorhinus and Barbodes, but it differs distinctly from all known genera.  Comparison in characteristics has been made.

卷期：18卷 01期

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