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[dinosaur] Theropod limb lengthening + Vitakrisaurus + titanosaurs + more (free pdfs)




Ben Creisler
bcreisler@gmail.com

Some recent papers with free pdfs:


T. Alexander Dececchi, Aleksandra Mloszewska, Hans Larsson, Thomas R Holtz Jr. & Michael Bruce Habib (2019)
The fast and the frugal: Divergent locomotory strategies drive limb lengthening in theropod dinosaurs
bioRxiv (preprint)
doi: https://doi.org/10.1101/785238
https://www.biorxiv.org/content/10.1101/785238v1.abstract?%3Fcollection=
Free pdf:
https://www.biorxiv.org/content/early/2019/09/27/785238.full.pdf



Limb length, cursoriality and speed have long been areas of significant interest in theropod paleobiology as locomotory capacity, especially running ability, is critical in not just in prey pursuit but also to avoid become prey oneself. One aspect that is traditionally overlooked is the impact of allometry on running ability and the limiting effect of large body size. Since several different non-avian theropod lineages have each independently evolved body sizes greater than any known terrestrial carnivorous mammal, ~1000kg or more, the effect that such larger mass has on movement ability and energetics is an area with significant implications for Mesozoic paleoecology. Here using expansive datasets, incorporating several different metrics to estimate body size, limb length and running speed, Âto calculate the effects of Âallometry Ârunning We test both on traditional metrics used to evaluate cursoriality in non-avian theropods such as distal limb length, relative hindlimb length as well as comparing the energetic cost savings of relative hindlimb elongation between members of the Tyrannosauridae and more basal megacarnivores such as Allosauroids or Ceratosauridae. We find that once the limiting effects of body size increase is incorporated, no commonly used metric including the newly suggested distal limb index (Tibia + Metatarsus/ Femur length) shows a significant correlation to top speed. The data also shows a significant split between large and small bodied theropods in terms of maximizing running potential suggesting two distinct strategies for promoting limb elongation based on the organismsâ size. For small and medium sized theropods increased leg length seems to correlate with a desire to increase top speed while amongst larger taxa it corresponds more closely to energetic efficiency and reducing foraging costs. We also find, using 3D volumetric mass estimates, that the Tyrannosauridae show significant cost of transport savings compared to more basal clades, indicating reduced energy expenditures during foraging and likely reduced need for hunting forays. This suggests that amongst theropods while no one strategy dictated hindlimb evolution. Amongst smaller bodied taxa the competing pressures of being both a predator and a prey item dominant while larger ones, freed from predation pressure, seek to maximize foraging ability. We also discuss the implications both for interactions amongst specific clades and Mesozoic paleobiology and paleoecological reconstructions as a whole.

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Some short conference papers more like expanded abstracts rather than full articles.


Malkani has also recently posted additional material on pterosaurs and dinosaurs up on Research Gate that I sorting through. I'm not sure if they count as formally published (although they have doi designations) and they may appear elsewhere at some point. I will do a post about that material when I can.

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Muhammad Sadiq Malkani (2019)
Vitakrisaurus saraiki Theropod from South Asia.
Open Journal of Geology 9(10): 643-645
DOI: 10.4236/ojg.2019.910063 Â
https://www.scirp.org/journal/paperabs.aspx?paperid=95289
Free pdf:
https://www.scirp.org/pdf/OJG_2019092316001486.pdf

Vitakrisaurus saraiki abelisauroid theropod dinosaurs reported from Pakistan and extended distribution into India. Vitakrisaurus saraiki is medium to large sized theropod which is represented by associated vertebral and limb elements and especially hand elements. Out of 14 small to large bodied theropods from Indo-Pakistan subcontinent, only less than half of these are restricted to some common elements. Vitakrisaurus saraiki theropod of Pakistan is based on associated vertebral and limb elements especially hand including articulated carpals, metacarpals, phalanges and claws which are significant for Gondwanan paleobiogeographic link, comparisons and systematic.


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Muhammad Sadiq Malkani (2019)
Large Titanosaur from Indo-Pakistan Peninsula.
Open Journal of Geology 9(10): 635-638
DOI: 10.4236/ojg.2019.910061 Â
https://www.scirp.org/journal/paperabs.aspx?paperid=95286
https://www.scirp.org/pdf/OJG_2019092315520771.pdf


Indo-Pakistan subcontinent is lucky to host the smallest, medium and large sized titanosaurian sauropod dinosaurs. Saraikimasoom is the smallest sized, and Gspsaurus is the medium sized transversely stocky, Pakisaurus and Isisaurus are the large sized titanosaurs of South Asia. Pakisaurus balochistani is a slender type of pakisaurid titanosaurian based on associated vertebral and appendicular skeletons. Pakisaurus balochistani includes key elements like transversely thin or narrow tibia and ventrally not reduced tall caudal vertebrae, along with other elements which are significant for cladistic analysis.

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Muhammad Sadiq Malkani (2019)
Medium Sized Stocky Titanosaur from South Asia.
Open Journal of Geology 9(10): 631-634
DOI: 10.4236/ojg.2019.910060
https://www.scirp.org/journal/paperabs.aspx?paperid=95285

Recently, four coexisted titanosaurs from latest Maastrichtian Vitakri Lameta Formation of Indo-Pakistan are recognized as Isisaurus and Pakisaurus of large-sized slender pakisaurids, Saraikimasoom and Gspsaurus of the smallest and medium sized transversely stocky gspsaurids. Gspsaurus pakistani based on associated skull (with conical teeth tapering gradually from base to tip), vertebral and appendicular elements found from Alam 19 locality of Vitakri area, Barkhan district, Balochistan, Pakistan, South Asia. Gspsaurus bears sufficient skeletal elements and can be used for evolutionary studies.
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Muhammad Sadiq Malkani (2019)
Smallest Titanosaur from Indo-Pakistan Landmass.
Open Journal of Geology 9(10): 627-630
DOI: 10.4236/ojg.2019.910059
https://www.scirp.org/journal/paperabs.aspx?paperid=95282
https://www.scirp.org/pdf/OJG_2019092315433230.pdf

Almost complete skulls of most derived titanosaurs which provide complete teeth row are rare. Saraikimasoom vitakri is the smallest sized, the most derived titanosaurian sauropod based on very small sized 15 - 18 cm long and 7 - 9 cm high partial skull. Dorsal profile of skull inclined 40Â anteriorly. It provides full teeth row with dental formula 4, 13/9-13. Saraikimasoom is the smallest titanosaur so far found from Indo-Pakistan subcontinent. Its height is about 2 meter, length 8 - 10 meter and weight about 5 tons. Saraikimasoom vitakri shows Gondwanan paleobiogeographic link with some endemic elements.

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Muhammad Sadiq Malkani (2019)
Induszalim bala Mesoeucrocodile from Pakistan.
Open Journal of Geology 9(10): 623-626
DOI: 10.4236/ojg.2019.910058 Â
https://www.scirp.org/journal/paperabs.aspx?paperid=95281
https://www.scirp.org/pdf/OJG_2019092315395635.pdf


Induszalim bala is the first diagnostic mesoeucrocodile from Indo-Pakistan subcontinent having rostrum articulated with dentary symphysis and associated vertebrae and limb bones and provides facility for comparison with other mesoeucrocodiles. Induszalim is a medium to large sized mesoeucrocodile found in the latest Maastrichtian Vitakri Lameta Formation of Fort Munro Group just below Cretaceous-Paleogene boundary line. Induszalim has sufficient skeletal elements and can be used for phylogenetic studies. Induszalim shows Gondwanan paleobiogeographic affinity with some endemic elements.

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Yongqing Liu, Hongwei Kuang, Kemin Xu, Zhenguo Ning, Nan Peng, Shengxian Du & Jun Chen (2019)
Cretaceous Stratigraphy, Paleoenvironment and Terrestrial Biota in Shandong Province.
Open Journal of Geology 9(10): 650-653
DOI: 10.4236/ojg.2019.910065.
https://www.scirp.org/journal/paperabs.aspx?paperid=95292
https://www.scirp.org/pdf/OJG_2019092316111105.pdf

The terrestrial upper Jurassic-Cretaceous (upper and lower)-Cenozoic stratigraphic succession developed continuously in Shandong province. There are intact and continuous terrestrial paleoecosystems dominated by dinosaurs, including five vertebrate fauna (bone fossil assemblages) beds from the bottom to top in the Cretaceous successions of Shandong Province. There are multiple vertebrate footprints (group) bearing beds in the transition period between Jurassic-Cretaceous and Early Cretaceous, and multiple large-scale dinosaur burial bone beds in Late Cretaceous. In recent years, it has also been found that extraterrestrial impact geological event may occur in the K/Pg transition over a hundred meters (siliceous pellet and gamma element anomalies, etc.). Shandong has a well-developed terrestrial Cretaceous succession with perfect information on paleoenvironment and paleoecology, which is an ideal area to explore the co-evolutionary relationship between terrestrial biota and paleoenvironment.

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Dhananjay M. Mohabey & ÂBandana Samant (2019)
Cretaceous-Paleogene Transition of Reptilian Tetrapods across Deccan Volcanism in India.
Open Journal of Geology 9(10): 639-642
DOI: 10.4236/ojg.2019.910062 Â
https://www.scirp.org/journal/paperabs.aspx?paperid=95287
https://www.scirp.org/pdf/OJG_2019092315561402.pdf

Eruptions of lava flows of Deccan large igneous province straddled the Cretaceous-Palaeogene boundary (K-Pg). Sediments associated at different stratigraphic levels within the lava piles of Deccan volcanic sequences (DVS) are mainly terrestrial. We studied the sediments of Eastern and Central Deccan Volcanic Province, and the Malwa Plateau for tracking changes in reptilian tetrapods across the volcanism. The reptiles are mainly represented by abelisaurid-titanosaurid dinosaurs, Alethinophidia madtsoiia snakes, Notosuchian crocodylomorph Simosuchus, bothremydid Kurmademydinae turtles and Anguimorph and Scincomorphs lizards. The evidences suggest that the non-avian dinosaurs were adversely affected by the arrival of the first volcanic flows locally in the province either within C30N or C29R Maastrichtian. The abelisaurid theropods became extinct whereas a single or two species of titanosauriforme dinosaurs survived but eventually became extinct at least 350 ky before the K-Pg boundary with increasing volcanism. The madtsooid snakes and crocodylimorphs were also adversely affected with decline in their diversity and abundance, whereas the Bothremydid turtles survived the initial onslaught of Deccan volcanism and continued across the K-Pg boundary.

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Phornphen Chanthasit, Suravech Suteethorn, Wilailak Naksri, Haiyan Tong, Kamonlak Wongko, Teppei Sonoda (2019)
New Vertebrate Fossil Site from the Early Cretaceous Sao Khua Formation, Sakon Nakhon Province, Northeastern Thailand.
Open Journal of Geology 9(10): 619-622
DOI: 10.4236/ojg.2019.910057
https://www.scirp.org/journal/paperabs.aspx?paperid=95278
https://www.scirp.org/pdf/OJG_2019092315322908.pdf

A new vertebrate fossil site, "Phu Sung" in Sakon Nakhon Province was discovered. Various vertebrate fossils belonging to fresh water shark, bony fish, turtle, crocodile and dinosaur were found in reddish silty mudstone of the Early Cretaceous Sao Khua Formation of the Khorat Group. Crocodilian remains including a complete skull and partial articulated skeleton are very well preserved associated with turtle remains. Moreover, well preserved 19 turtle shells were found accumulated together. These discoveries will certainly fulfill our knowledge about these aquatic taxa from the Early Cretaceous Sao Khua Formation. The exceptional preservation of Phu Sung fossils could probably relate to the paleoenvironment in the Early Cretaceous of Thailand.