It's been quiet here lately as I finish the coelurosaur phylogeny. But those of you who are fans of Microvenator? "chagyabi", "Tyrannosaurus" lanpingensis, Prodeinodon? "tibetensis" and "Megacervixosaurus tibetensis" will have cause to rejoice, since I'll soon have Zhao 1986 in my hands.
Zhao, 1986. The Cretaceous biota of China: Reptilia. in Hao, Su, Yu, Li, Li, Wang, Qi, Guan, Hu, Liu, Yang, Ye, Shou and Zang (eds.). The Cretaceous System of China. Stratigraphy of China. 12, 67-73, plates XI, XII.
To me is very useful article by Zhao 1986.
ReplyDeleteI sent the work where the dinosaurs come from Brazil. I hope and I give away a diagnosis in your blog.
regards
Rexisto
Thanks for the Brazilian articles Freire et al. (2007) and Medeiros et al. (2007).
ReplyDeleteThe eleven Alcantara teeth that are said to resemble Malawisaurus are not actually referred to that genus by Freire et al., and no Malawisaurus synapomorphies are listed. The characters ("spatulated but rather tongue-shaped, with a well defined D outlining the cross-section at the median portion of the crown") are found in other basal tiranosauriforms.
The ten Alcantara teeth that are said to resemble iguidiensis are again not united with it based on synapomorphies, but are instead only said to be "quite similar in size and morphology." They are also described very poorly, without mention of serration density or serration shape, for instance. Medeiros et al. only call them Theropoda indet.. Of course, iguidiensis' teeth are described even worse by Lapparent (1960), with the total description being "Forty-nine theropod teeth, smaller, more elongate, clearly more curved, and thinner
than the large teeth of Carcharodontosaurus." Wow. And since they're only illustrated in labial/lingual view, all we can compare are basic outlines. And those outlines differ greatly between teeth, with some (plate V, figure 11) being slender and highly recurved, while others (plate V, figure 13) are stout with an almost straight distal edge. This isn't surprising since they come from at least four localities across Africa, so there could easily be multiple taxa involved. In short, iguidiensis teeth are too varied and poorly described for any material to be said to resemble it more closely than other theropods.
The assignment of Brazilian teeth to Carcharodontosaurus is not defended, but the cited paper (Vilas Boas et al., 1999; which I don't have) calls Carcharodontosaurus a tyrannosaurid, so I'm not very hopeful they compared the teeth to Giganotosaurus and Mapusaurus.
Apparently in a thesis Zhao originally created after the names mentioned but not described publicly in an article!
ReplyDeleteYup. As the Database says, Olshevsky (DML, 1999) reported the IVPP rejected Zhao's thesis as unpublishable. It was originally supposed to be the "Zhao, 1983. The Mesozoic vertebrate remains of Xizang (Tibet), China. The Series of the Scientific Expeditions to the Qinghai-Xizang Plateau. Palaeontology of Xizang. 2, 1-200." listed in Zhao's 1983 APP paper.
Delete