重庆万州盐井沟动物群首次发现小猪头骨化石  

The first discovery of Sus xiaozhu skulls from Yanjinggou fauna in Wanzhou,Chongqing

作　　者：胡海虔 余海东 魏光飚 熊璨 林雨 王荀仟 HU Haiqian;YU Haidong;WEI Guangbiao;XIONG Can;LIN Yu;WANG Xunqian(Chongqing Key Laboratory of Paleontology and Paleoenvironment Co-evolution(Sichuan-Chongqing Joint Construction),No.208 Hydrogeological and Engineering Geological Team,Chongqing Bureau of Geological and Mineral Resource Exploration and Development,Chongqing 400700;Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences,Institute of Vertebrate Paleontology and Paleoanthropology,Chinese Academy of Sciences,Beijing 100044;University of Chinese Academy of Sciences,Beijing 100049;Chongqing Institute of Geological Survey,Chongqing 401122)

机构地区：[1]重庆市地质矿产勘查开发局208水文地质工程地质队(重庆市地质灾害防治工程勘查设计院),川渝共建古生物与古环境协同演化重庆市重点实验室,重庆400700 [2]中国科学院古脊椎动物与古人类研究所,中国科学院脊椎动物演化与人类起源重点实验室,北京100044 [3]中国科学院大学,北京100049 [4]重庆市地质调查院,重庆401122

出　　处：《第四纪研究》2023年第3期793-802,共10页Quaternary Sciences

基　　金：重庆市规划和自然资源局《重庆市重要古生物化石资源保护研究》项目(批准号:ZC-2021018)资助。

摘　　要：重庆万州盐井沟是中国南方最经典的第四纪哺乳动物化石产地之一,因化石数量众多、种类多样和完整度极高而著名,但目前重庆万州盐井沟动物群已报道的猪科动物化石仅为野猪(Sus scrofa)和猪属未定种(Sus sp.)。现今可考证的化石点为建国以后发现的4个化石点,即大垭口化石点、平坝上洞、平坝下洞和媒人洞,而四方地化石点是重庆万州盐井沟地区新近发现的第5个化石点,出土了亚成年小猪(Sus xiaozhu)的2件不完整头骨和2件下颌骨化石,代表了迄今发现最完整且时代最晚(晚更新世)的小猪头骨和下颌骨化石,为盐井沟动物群中首次发现。经过与华南第四纪猪属(Sus)其他物种对比,小猪的鉴定特征可归纳为小型猪,面部和腭骨长度远不及李氏野猪(S.lydekkeri)和野猪(S.scrofa),牙齿尺寸小于裴氏猪(S.peii)、李氏野猪(S.lydekkeri)和野猪(S.scrofa),眶前孔位于DP4(P4)与M1界线之上,下颌骨联合部短且厚,终止于P2之前。雄性下犬齿横切面的形状介于“verrucose”型和“scrofa”型之间,属于一种过渡类型,臼齿低冠且呈丘型,结构简单,每个臼齿由4个主尖组成,前臼齿齿列比臼齿齿列长,m3跟座仅发育1~2个齿尖。小猪(S.xiaozhu)与野猪(S.scrofa)的同时出现,可作为华南中-晚更新世哺乳动物群的一个标志。The Yanjinggou area in Wanzhou District,Chongqing Municipality,has long been considered as one of the most typical localities of Quaternary mammalian fossils in South China,with numerous complete crania and postcranial skeletons serving as significant reference materials for classification and biochronology.However,most localities are difficult to trace due to a lack of geographical coordinates and horizons in historical excavations and acquisitions,with the exception of four later localities discovered after the founding of the People's Republic of China.On the other hand,the Dayakou site,the Upper Cave of Pingba,the Lower Cave of Pingba and the Meiren cave are the only four verifiable localities until now.The Sifangdi site(30°33′01″N,108°23′00″E;1256m a.s.l.)is near Laowu Village,Zouma Town in Wanzhou,Chongqing,approximately 8km northwest of the Upper Cave of Pingba in the Yanjinggou area.The Sifangdi site is a vertical pit with an azimuth angle of 305°,a maximum length of 5.5m,a maximum width of 2.9m,and a depth of about 7.5m,which lies on the hillside of limestone from the Jialingjiang Formation in the Lower Triassic.The deposits,with a thickness of 7.5m,can be divided into three layers from top to bottom based on the lithology and occurrences.The upper layer is a secondary clay without fossils,while the middle brownish-yellow clay layer(bearing Sus xiaozhu)and the lower brownish-red layer mixed up with limestone breccias contain rich fossil records.Fossil assemblages of larger mammals indicate a late Pleistocene fauna quite close to the extant mammalian fauna in South China,consisting of Trachypithecus sp.,Hystrix sp.,Ursus thibetanus,Dicerorhinus sumatrensis,S.xiaozhu,S scrofa,Bubalus sp.,Bos(Bibos)gaurus granger,Rusa unicolor,Muntiacus reevesi and Muntiacus muntjak.Two incomplete skulls and two incomplete mandibles of S.xiaozhu recovered from the Sifangdi site represent the best-preserved,the latest remains and the first discovery of S.xiaozhu in the Yanjinggou area,demonstrating that S.xiaozhu

关 键 词：小猪 形态分类学 晚更新世 四方地化石点 万州盐井沟动物群 

分 类 号：P534.631[天文地球—第四纪地质学] Q915.876[天文地球—古生物学与地层学]