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通过对贵州关岭上三叠统卡尼阶法郎组瓦窑段地层中的两件关岭鱼龙属标本的观察、测量,并与早侏罗世鱼龙标本对比研究,发现晚三叠世的关岭鱼龙尾椎中部存在一定数量形态发生变化的侧视呈梯形的椎体,已经具有了传统观点认为只在侏罗纪和白垩纪鱼龙中出现的尾弯,弯角为15°左右(侏罗纪鱼龙尾弯弯角可达60°)。这一衍生性状的出现表明晚三叠世关岭鱼龙已经在一定程度上具有了鼎盛时期鱼龙所拥有的尾鳍,并已获得了较强的游泳能力,开始成为完全适应远洋快速游泳的生物,并将以前认为截然分离的三叠纪的早期鱼龙类群与侏罗纪-白垩纪鼎盛时期特化的鱼龙类群联系起来,是鱼龙目单系起源的又一例证。
Through the observation and measurement of two specimens of the genus Ichthyosaur from the Upper Triassic Carni Fonglang Formation in the Guanling Formation, Guanling, Guizhou, and comparison with the Early Jurassic specimens, we found that the Late Triassic Of the Guanling fish tail caudal vertebra in the middle there are a certain number of morphological changes in the lateral trapezoidal vertebra, already has the traditional view that appears only in the Jurassic and Cretaceous cichlid fish tail bend, the angle of 15 ° (Jurassic fish tail bend angle of up to 60 °). The emergence of this derivative trait indicates that the Late Triassic Guanling crayfish had, to some extent, the caudal fin possessed by the lizard during its heyday and had acquired a strong ability to swim and became a creature fully adapted to rapid ocean-going swimming , And linking earlier Triassic early-stage Ichneumonidae, previously thought to be distinct from that of the Jurassic-Cretaceous-characterized Ichthyosaur, is yet another example of the origin of the Monoceras.