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[dinosaur] Tyrannosaur walking speed + archosauriform teeth from Triassic of Brazil + more





Ben Creisler
bcreiser@gmail.com


Some recent papers:



Javier Ruiz (2017)
Comments on “A tyrannosaur trackway at Glenrock, Lance Formation (Maastrichtian), Wyoming” (Smith et al., Cretaceous Research, v. 61, pp. 1–4, 2016).
Cretaceous Research (advance online publication)
https://doi.org/10.1016/j.cretres.2017.05.033
http://www.sciencedirect.com/science/article/pii/S0195667117301891

The paper by Smith et al. (2016) included speed calculations performed from a tyrannosaur trackway at Glenrock, Lance Formation, Wyoming. These authors concluded that tyrannosaurs walked in speeds similar to those obtained for other large theropod, but faster than proposed for hadrosaurids, a potential prey. However, the calculations performed by Smith et al. (2016) suffered from methodological and computational errors, which greatly affected the reported results. Here I show that when speeds are correctly calculated from the Glenrock trackway, the obtained values are clearly (about 50–80 percent) higher than the wrong values quoted by these authors. This support even more a significant speed capability for tyrannosaurs that claimed by Smith et al. (2016).

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Free pdf:

Tiane Macedo de Oliveira & Felipe L. Pinheiro (2017)
Isolated archosauriform teeth from the Upper Triassic Candelária Sequence (Hyperodapedon Assemblage Zone, Southern Brazil).
Revista Brasileira de Paleontologia 20(2): 155-162
doi: 10.4072/rbp.2017.2.01
http://www.sbpbrasil.org/assets/uploads/files/rbp20-2/01_Oliveira_%26_Pinheiro_RBP_v20_n2_COR.pdf



We describe isolated teeth found in the locality “Sítio Piveta” (Hyperodapedon Assemblage Zone, Candelaria Sequence, Upper Triassic of the Paraná Basin). The material consists of five specimens, here classified into three different morphotypes. The morphotype I is characterized by pronounced elongation, rounded base and symmetry between lingual and labial surfaces. The morphotype II presents serrated mesial and distal edges, mesial denticles decreasing in size toward the base, distal denticles present until the base and asymmetry, with a flat lingual side and rounded labial side. The morphotype III, although similar to morphotype II, has a greater inclination of the posterior carinae. The conservative dental morphology in Archosauriformes makes difficult an accurate taxonomic assignment based only on isolated teeth. However, the specimens we present are attributable to “Rauisuchia” (morphotype II and III) and, possibly, Phytosauria (morphotype I). The putative presence of a phytosaur in the Carnian Hyperodapedon Assemblage Zone would have impact in the South American distribution of the group. The taxonomic assignments proposed herein contribute to the faunal composition of the Hyperodapedon Assemblage Zone, a critical unit on the study of the Upper Triassic radiation of archosaurs.


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Free pdf:

Only one vertebrate, Cretaceogekko (p. 358) , but may be of interest:


Guo, M.X., Xing, L.D., Wang, B., Zhang, W.W., Wang, S., Shi, A.M., Bai, M. 2017.

A catalogue of Burmite inclusions.

Zoological Systematics 42(3): 249–379. 

DOI: 10.11865/zs.201715

http://www.zootax.com.cn/EN/abstract/abstract183.shtml



Burmite (Burmese amber) from the Hukawng Valley in northern Myanmar is a remarkable valuable and obviously the most important amber for studying terrestrial diversity in the mid-Cretaceous. The diversity of Burmite inclusions is very high and many new taxa were found, including new order, new family/subfamily, and new genus. Till the end of 2016, 14 phyla, 21 classes, 65 orders, 279 families, 515 genera and 643 species of organisms are recorded, which are summized and complied in this catalogue. Among them, 587 species are arthropods. In addtion, the specimens which can not be identified into species are also listed in the paper. The information on type specimens, other materials, host and deposition of types are provided.



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Free pdf:


HE Jinrui, JIAO Runcheng, NAN Yun, HAO Chunyan, ZHANG Lingling, RAN Shuhong, SONG Qingwei, ZHANG Yichao, ZHAO Danning & CHENG Suzhen (2017)

Tuchenzi fossils and paleoclimate sedimentary environment in Qianjiadian basin of Yanqing County: Suspected dinosaur bones discovered for the first time in Yanqing, Beijing.

Geological Bulletin of China 36(8): 1319-1329

http://dzhtb.cgs.cn/ch/reader/view_abstract.aspx?file_no=20170802&flag=1


Free pdf:

http://dzhtb.cgs.cn/ch/reader/create_pdf.aspx?file_no=20170802&flag=1&journal_id=gbc&year_id=2017



The Tuchengzi Formation in Qianjiadian Basin of Yanqing County is composed of three lithologic members:the first member mainly consists of polymictic gravel and glutenite, the second member mainly consists of purplish red shale and argillaceous sandstone, and the third member mainly consists of compound gravel and gravel-bearing grit sandstone. A lot of fossils found in the second member have been reported, such as bivalves, conchostracans,Palaeontologists, plant fossils and dinosaur footprint. Neverthe-less, no relevant reports on the fossils of ostracods, sporopollen and dinosaur bones are found. In this study, the suspected dinosaur bone fossils were discovered for the first time in the second member of the Tuchengzi Formation in Qianjiadian Basin of Yanqing County, and LA-ICP-MS zircon U-Pb dating of the argillaceous sandstone was carried out. According to the age values of the low-er part of the first member (15.762±0.69Ma,) and the upper part of the second member (157.13±0.96Ma), the formation age of the Tuchengzi should be early Late Jurassic. On the basis of previous studies, the ancient climate and sedimentary environment of the Qianjiadian basin are discussed.


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