A new specimen (CAGS V 382)(Figs. 1～2) was described and a new species, Parakannemeyeria chengi , was erected based on this specimen. This material was found in the lower part of the Kelamayi Formation (Middle Triass...A new specimen (CAGS V 382)(Figs. 1～2) was described and a new species, Parakannemeyeria chengi , was erected based on this specimen. This material was found in the lower part of the Kelamayi Formation (Middle Triassic) of Jimusar, Xinjiang by Professor Cheng Zhengwu. It was identified as Parakannemeyeria by: skull curved, long, narrow and high; preorbital length more than 45% of skull length; the width between orbits less than 40% of the skull length; occipital plate high and narrow. But it also has some characters used to be thought as the diagnosis of Sinokannemeyeria such as broad intertemporal region, reduced nasal middle ridge; these two characters are enough to distinguish this specimen from all other Parakannemeyeria . A cladistic analysis was done for the phylogenetic relationship of Parakannemeyeria chengi among all known species of Sinokannemeyeria, Parakannemeyeria and Xiyukannemeyeria using the characters and data matrix of Liu and Li (2003), only adding the character states of P. chengi (Table 1). A shortest tree was obtained, it is nearly the same as the tree of Liu and Li (2003), other than P. chengi is the sister group of P. shenmuensis . The autopomorphies of P. chengi are indistinct mid nasal ridge, wide intertemporal region mainly formed by parietal (and interparietal), the posterior part of jugal arch nearly triangular in cross section.展开更多
文摘A new specimen (CAGS V 382)(Figs. 1～2) was described and a new species, Parakannemeyeria chengi , was erected based on this specimen. This material was found in the lower part of the Kelamayi Formation (Middle Triassic) of Jimusar, Xinjiang by Professor Cheng Zhengwu. It was identified as Parakannemeyeria by: skull curved, long, narrow and high; preorbital length more than 45% of skull length; the width between orbits less than 40% of the skull length; occipital plate high and narrow. But it also has some characters used to be thought as the diagnosis of Sinokannemeyeria such as broad intertemporal region, reduced nasal middle ridge; these two characters are enough to distinguish this specimen from all other Parakannemeyeria . A cladistic analysis was done for the phylogenetic relationship of Parakannemeyeria chengi among all known species of Sinokannemeyeria, Parakannemeyeria and Xiyukannemeyeria using the characters and data matrix of Liu and Li (2003), only adding the character states of P. chengi (Table 1). A shortest tree was obtained, it is nearly the same as the tree of Liu and Li (2003), other than P. chengi is the sister group of P. shenmuensis . The autopomorphies of P. chengi are indistinct mid nasal ridge, wide intertemporal region mainly formed by parietal (and interparietal), the posterior part of jugal arch nearly triangular in cross section.
