胡氏贵州龙新生个体形态学特征  

Characteristics of the newborns of Keichousaurus hui.(Reptilia Sauropterygia)from Xingyi Fauna(Ladinian,Middle Triassic),Guizhou Province

作　　者：温谦谦 张启跃[2] 闵筱 周长勇[2] 文芠[2,3] 胡世学 黄金元[2] WEN Qianqian;ZHANG Qiyue;MIN Xiao;ZHOU Changyong;WEN Wen;HU Shixue;HUANG Jinyuan(College of Earth Sciences and Engineering,Shandong University of Science and Technology,Qingdao 266590,China;Chengdu Center,China Geological Survey,Chengdu 610081,China;Nanjing university,Nanjing 210023,China)

机构地区：[1]山东科技大学地球科学与工程学院,山东青岛266590 [2]中国地质调查局成都地质调查中心,四川成都610081 [3]南京大学,江苏南京210023

出　　处：《沉积与特提斯地质》2022年第4期556-571,共16页Sedimentary Geology and Tethyan Geology

基　　金：中国地质调查局项目(DD20160020,DD20190054)资助。

摘　　要：本文观察并测量了中三叠世拉丁期兴义动物群中的12件包含胚胎的胡氏贵州龙化石及已产出的49个幼体胡氏贵州龙标本;对成年个体与新生个体的体长、肱骨长、股骨长与眼眶长径的特定性状比率关系进行了统计分析;展示了成年个体、胚胎及幼年个体的特征差异,首次描述了胡氏贵州龙新生个体形态学特征;定量刻画了胡氏贵州龙新生个体的头骨、颈椎、背椎、荐椎、尾椎和四肢,获得了更完整、精确的解剖学信息。新材料揭示胡氏贵州龙新生个体的头骨平均长度为8.56mm,肱骨明显短于股骨,肱股比例为1∶1.09。头部呈饱满的三角形,吻部短而钝,眼眶大而圆,具有独特的狭长型上颞孔。此外,研究发现胡氏贵州龙的生产方式为胎儿头部首先从母体产道产出,同时新生个体的吻—臀距稳定在31.04~32.26mm这个数值范围内,且该数值的变动与母体大小无直接联系。本次研究为胡氏贵州龙的生殖方式、个体发育、特别是异速生长研究提供了新的材料。In this paper,12 specimens with embryos and 49 newborns of the Keichousaurus hui from the Xinyi fauna of the Ladinian,the Middle Triassic are observed and measured.The ratio relationships of specific traits of body length,length of the humerus,femur and orbital length of the adult individuals and newborns have been carried on the statistical analysis.The characteristics of adult,embryo and young individuals are demonstrated,and the morphological characteristics of newborn of the Keichousaurus hui are described for the first time.The skull,cervical vertebra,dorsal vertebra,sacral vertebra,caudal vertebra and limbs of newborns of the Keichousaurus hui are quantitatively described.Besides,more complete and accurate anatomical information is obtained.The new materials show that the average length of the skull is 8.56 mm,the humerus is shorter than the femur,and the ratio of humerus/femur is 1∶1.09.The head is triangular,the snout is short and blunt,the orbit is large and round with a unique narrow superior temporal foramen.In addition,it is demonstrated that the fetal head of the Keichousaurus hui is firstly produced from the maternal birth canal.Meanwhile,the distance between snout and hip of the newborns keep stable with a range of 31.04~32.26 mm.Furthermore the change of this value is not directly related to the maternal size.This study provides new materials for the research of reproductive mode,ontogeny,especially allallic growth of the Keichousaurus hui.

关 键 词：胡氏贵州龙 新生个体 生殖方式 中三叠世 兴义动物群 

分 类 号：Q915.4[天文地球—古生物学与地层学]