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[dinosaur] Captorhinid from Upper Permian of Mallorca + turtle skull variation + scavenging + more





Ben Creisler
bcreisler@gmail.com


Some recent non-dino papers that may be of interest:



Torsten Liebrecht, Josep Fortuny, Àngel Galobart, Johannes Müller & P. Martin Sander (2016)
A large, multiple-tooth-rowed captorhinid reptile (Amniota: Eureptilia) from the upper Permian of Mallorca (Balearic Islands, western Mediterranean).
Journal of Vertebrate Paleontology: e1251936 
DOI: 10.1080/02724634.2017.1251936.
http://www.tandfonline.com/doi/full/10.1080/02724634.2017.1251936

MORADISAURINAE incertae sedis

Excerpt:

A specimen referred to Moradisaurinae incertae sedis (MBCN 15730) is the first record of a vertebrate body fossil from the Permo-Triassic of the island of Mallorca (Balearic Islands, western Mediterranean) that can be identified on a relatively low taxonomic level. The material consists of a partial maxillary tooth plate and adhering parts of the palate. The maxilla bears three rows of deeply implanted teeth that are subparallel to each other and to the margins of the tooth plate. The teeth are bulbous-conical, and those in the posterior part of the middle tooth row have a rounded anterior (mesial) and a straight posterior (distal) margin in occlusal view and show a distinctive wear pattern of deep grooves running vertically down the lingual and/or labial sides of the crown. The teeth in the lingual and labial tooth rows are elliptical or teardrop-shaped in cross-section, with the long axis forming an angle of about 45° to the midline of the tooth plate. Because the available anatomical information is almost exclusively restricted to dental characters, an assignment of the specimen to a distinctive species or genus is not possible at this time. Based on dentition, size, and stratigraphy, it nevertheless can be clearly considered as a representative of the Captorhinidae. The cladistic analysis reveals that it probably belongs to the captorhinid subclade Moradisaurinae, even though statistical support for its relationship to other moradisaurines is weak.


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Christian Foth, Márton Rabi and Walter G. Joyce (2016)
Skull shape variation in extant and extinct Testudinata and its relation to habitat and feeding ecology.
Acta Zoologica (advance online publication)
DOI: 10.1111/azo.12181
http://onlinelibrary.wiley.com/doi/10.1111/azo.12181/full

Turtles (Testudinata) are a diverse group of reptiles that conquered a broad set of habitats and feeding ecologies over the course of their well-documented evolutionary history. We here investigate the cranial shape of 171 representatives of the turtle lineage and the relationship of shape to different habitat and diet preferences using two-dimensional geometric morphometrics. The skull shape of extant turtles correlates with both ecological proxies, but is more affected by habitat than diet. However, the application of these correlations to extinct turtles produces mostly flawed results, as least when compared to external data such as sedimentary environment, highlighting that the morphospace held by extant turtles is not necessarily the optimal location in tree space for a particular ecology. The inability of this study to correctly predict the ecology of extinct turtles is likely related to the fact that the shape of turtle skulls is dominated by the emarginations and jaw closure mechanisms, two shape features unrelated to habitat or feeding ecology. This indicates that various specializations that are apparent in the skull only contribute little to overall shape.


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Adam Kane, Kevin Healy, Thomas Guillerme, Graeme D. Ruxton and Andrew L. Jackson (2016)
A recipe for scavenging in vertebrates – the natural history of a behaviour.
Ecography (advance online publication)
DOI: 10.1111/ecog.02817
http://onlinelibrary.wiley.com/doi/10.1111/ecog.02817/full


Despite its prevalence, the importance of scavenging to carnivores is difficult to ascertain in modern day forms and impossible to study directly in extinct species. Yet, there are certain intrinsic and environmental features of a species that push it towards a scavenging lifestyle. These can be thought of as some of the principal parameters in optimal foraging theory namely, encounter rate and handling time. We use these components to highlight the morphologies and environments that would have been conducive to scavenging over geological time by focusing on the dominant vertebrate groups of the land, sea and air. The result is a synthesis on the natural history of scavenging. The features that make up our qualitative scale of scavenging can be applied to any given species and allow us to judge the likely importance of this foraging behaviour.


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Source of many tetrapod fossils....

Sharane S.T. Simon and Martin R. Gibling (2016)
Fine-grained meandering systems of the Lower Permian Clear Fork Formation of north-central Texas, USA: Lateral and oblique accretion on an arid plain.
Sedimentology (advance online publication)
DOI: 10.1111/sed.12322
http://onlinelibrary.wiley.com/doi/10.1111/sed.12322/full


Facies models that adequately represent the diverse range of fine-grained fluvial systems are currently lacking from the literature. In this paper, the spectrum of these systems on the arid plains of western equatorial Pangea is explored, as well as the source and nature of the fine-grained sediments. Eight fluvial elements in the Early Permian Clear Fork Formation of north-central Texas represent channel systems up to 7 m deep with coarse basal deposits, three types of lateral-accretion deposits and sandstone sheets, with laminated, disrupted and massive mudstones laid down in abandoned channels and on floodplains. The three fine-grained fluvial styles represent a continuum between two end-members: sustained lateral accretion of bedload composed of quartzose sediments and mud aggregates on point bars, and oblique accretion of suspended sediment on steep accretionary benches and banks with limited lateral migration. This spectrum is controlled, in part, by grain size and the proportion of suspended to bedload sediments. The presence of rarely documented swept ripples on exhumed accretion surfaces is attributed to rapid decline in water levels and downstream re-entry of overbank floodwaters into the channel. Rill casts, roots and disrupted mudstones low down in channel bodies indicate periods of near-dryness. Laterally extensive sheet sandstones were formed by episodic flows in broad, sandbed channels. The fluvial sediments were primarily intrabasinally sourced with extrabasinal sediments brought in during major floods from upland source areas or reworked from local storage in the basin, representing a supply limited system. The upward change in cement composition from mainly calcite and ankerite to dolomite and gypsum with minor celestine implies increasingly saline groundwater and progressive aridification, supporting Late Palaeozoic palaeoclimatic models. By integrating petrographic data with sedimentology, a plethora of information about ancient landscapes and climate is provided, allowing a fuller comparison between the Clear Fork Formation and modern dryland alluvial plains.



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The official English version of a paper posted earlier from the original Russian source:


N. V. Zelenkov (2016) 
Revision of non-passeriform birds from Polgárdi (Hungary, Late Miocene): 2. Galliformes
Paleontological Journal 50(6): 623–634
DOI: 10.1134/S0031030116060162
http://link.springer.com/article/10.1134/S0031030116060162

A taxonomic revision of Galliformes (Aves) from the Upper Miocene of Polgárdi has confirmed the presence of five taxa. A large pheasant originally described as Pavo aesculapi phasianoides Jánossy, 1991 is referred to the genus Syrmaticus as a valid species, S. phasianoides (Jánossy, 1991), comb. nov. Small phasianids are represented in Polgárdi by four taxa: Mioryaba magyarica gen. et sp. nov., Eurobambusicola turolicus gen. et sp. nov., Plioperdix hungarica (Jánossy, 1991), and a form similar in size to Mioryaba magyarica, but having a more primitive structure of the tarsometatarsus and carpometacarpus.