产自中国云南下禄丰组(下侏罗统)的爬行动物不完美硕鳄的再研究(英文)

一般认为植龙类在三叠纪末期灭绝,但有研究显示它们可能在欧洲和亚洲延续到了侏罗纪最早期。来自亚洲的证据是产自中国云南下禄丰组(?赫唐阶-锡内穆阶)的不完美硕鳄(Pachysuchus imperfectus)。重新研究显示不完美硕鳄正型标本和植龙类存在许多不同点,它可能属于一个保存较差的、分类位置无法确定的蜥脚型类恐龙头骨。这一属种的归入标本也无法明确归入某一类群,因此亚洲没有可靠的晚于三叠纪的植龙类化石记录。欧洲的侏罗纪植龙类化石也存在着同样的问题。因而认为,植龙类的化石记录仅限于三叠纪晚期。

THE ENIGMATIC REPTILE PACHYSUCHUS IMPERFECTUS YOUNG, 1951FROM THE LOWER LUFENG FORMATION ( LOWER JURASSIC )OF YUNNAN, CHINA

Phytosaurs are generally considered to have become extinct at the end of the Triassic Period,but several records have suggested that they survived into the basal Jurassic in Europe and Asia.The Asian record consists of Pachysuchus imperfectus from the Lower Lufeng Formation(?Hettangian-Sinemurian) of Yunnan,China.However,this specimen differs from phytosaurs in numerous respects and is more likely a poorly preserved,indeterminate sauropodomorph dinosaur skull.The referred specimens of this species are also regarded as indeterminate,thereby removing the post-Triassic record of phytosaurs from Asia.The European records of Jurassic phytosaurs are also shown to be doubtful,suggesting that this clade was restricted to the Late Triassic.