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[Ornithology • 2017] Myzomela irianawidodoae • A Colourful New Species of Myzomela Honeyeater from Rote Island in eastern Indonesia ---ScRaBBlE

Myzomela irianawidodoae Prawiradilaga, Baveja, Suparno, Ashari, Ng, Gwee, Verbelen & Rheindt, 2017  photo:   Philippe Verbelen  e-journ...

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Showing posts with label Durophagy. Show all posts
Showing posts with label Durophagy. Show all posts

Wednesday, March 20, 2019

[PaleoMammalogy • 2017] Anatoliadelphys maasae • Skeleton of An Unusual, Cat-sized Marsupial Relative (Metatheria: Marsupialiformes) from the middle Eocene (Lutetian) of Turkey ---ScRaBBlE


Anatoliadelphys maasae  Maga & Beck, 2017


Abstract

We describe a near-complete, three-dimensionally preserved skeleton of a metatherian (relative of modern marsupials) from the middle Eocene (Lutetian: 44–43 million years ago) Lülük member of the Uzunçarşıdere Formation, central Turkey. With an estimated body mass of 3–4 kg, about the size of a domestic cat (Felis catus) or spotted quoll (Dasyurus maculatus), it is an order of magnitude larger than the largest fossil metatherians previously known from the Cenozoic of the northern hemisphere. This new taxon is characterised by large, broad third premolars that probably represent adaptations for hard object feeding (durophagy), and its craniodental morphology suggests the capacity to generate high bite forces. Qualitative and quantitative functional analyses of its postcranial skeleton indicate that it was probably scansorial and relatively agile, perhaps broadly similar in locomotor mode to the spotted quoll, but with a greater capacity for climbing and grasping. Bayesian phylogenetic analysis of a total evidence dataset comprising 259 morphological characters and 9kb of DNA sequence data from five nuclear protein-coding genes, using both undated and “tip-and-node dating” approaches, place the new taxon outside the marsupial crown-clade, but within the clade Marsupialiformes. It demonstrates that at least one metatherian lineage evolved to occupy the small-medium, meso- or hypo-carnivore niche in the northern hemisphere during the early Cenozoic, at a time when there were numerous eutherians (placentals and their fossil relatives) filling similar niches. However, the known mammal fauna from Uzunçarşıdere Formation appears highly endemic, and geological evidence suggests that this region of Turkey was an island for at least part of the early Cenozoic, and so the new taxon may have evolved in isolation from potential eutherian competitors. Nevertheless, the new taxon reveals previously unsuspected ecomorphological disparity among northern hemisphere metatherians during the first half of the Cenozoic.


Systematic palaeontology

Mammalia; Theria
Metatheria; Marsupialiformes

Anatoliadelphys gen. nov.  
Anatoliadelphys maasae sp. nov.  

Etymology: Anatolia (Greek): the geographic name for the Asian part of Turkey; delphys (Greek): uterus, a common suffix for marsupials and their fossil relatives; maasae: in honour of Dr. Mary Maas and her contributions to Paleogene mammalian palaeontology, particularly in Turkey.

Holotype: Ankara Üniversitesi Jeoloji Müzesi (AÜJM) specimen 2002–25, which comprises a fragmented partial cranium, both dentaries, and associated postcranial elements, including most of the vertebral column, partial pectoral and pelvic girdles, all of the long limb bones, both calcanei, two metapodials, and a few phalanges.

Locality and age: AÜJM 2002–25 was collected from the Lülük member of the Uzunçarşıdere Formation (UCF), which is part of the small Orhaniye-Güvenç sedimentary basin located at the northwestern edge of the city of Ankara, approximately 5 km southwest of the town of Kazan, in central Turkey. The Lülük member is the lowest of the three members currently recognised within the UCF (together with the Gökdere [middle], and Sarıbeyler [upper] members), and is the source of all fossil mammals known from the UCF to date. AÜJM 2002–25 is from locality AK33, which is approximately 90m above the base of the UCF, at Memlik village. Until recently, the age of the UCF was poorly constrained, but a combination of U-Pb dating of zircons and magnetostratigraphy now support a date of 44–42 MYA (= Lutetian) for the formation as a whole, and 44–43 MYA for the Lülük member.

Diagnosis: Anatoliadelphys maasae differs from all other metatherians in the following combination of features: comparatively large size (estimated body mass 3–4 kg); premolars increase markedly in size posteriorly (occlusal area of p1 less than one sixth that of p3); P3 and p3 very large (similar in occlusal area to M2 and m2 respectively) and also broad (labiolingual width:mesiodistal length ratio is 0.89 for P3 and 0.7 for p3); modified tribosphenic molar dentition, in which M1-3 and m1-4 increase markedly in size posteriorly (occlusal area of M1 approximately one third that of M3; occlusal area of m1 approximately one seventh that of m4); upper molars with cingula extending along the anterior and posterior margins; protocone large but conules indistinct or absent; metacone taller than the paracone on M3 but smaller than the paracone on M4; centrocrista v-shaped on M3, with the premetacrista extending labially to stylar cusp D; centrocrista straight on M4; parastylar lobe very large on M4; anterior cingulid weakly developed on m3-4; m4 trigonid dominated by enormous protoconid, with paraconid and metaconid both greatly reduced; preentocristid and cristid obliqua of m3-4 both with carnassial notch; posterior cingulid present but very faint on m3-4; strongly curved radius and tibia; femur with prominent third trochanter, well-marked trochlea and distal condyles of approximately equal width; calcaneus with medially-inflected tuber, large peroneal process with prominent groove for peroneus longus tendon, concave calcaneocuboid facet, and prominent pit (probably for plantar calcaneocuboid ligament) on ventral surface.

.....

Fig 1. Holotype skeleton of Anatoliadelphys maasae (AÜJM 2002–25). Scale bar = 5 cm. 

Reconstruction of the Anatoliadelphys maasae.
Illustration: Peter Schouten 


A. Murat Maga and Robin M. D. Beck. 2017. Skeleton of An Unusual, Cat-sized Marsupial Relative (Metatheria: Marsupialiformes) from the middle Eocene (Lutetian: 44-43 million years ago) of Turkey.  PLoS ONE. 12(8); e0181712.  DOI: 10.1371/journal.pone.0181712


Cenozoic carnivore from Turkey may have evolved without placental competitors  phy.so/422094230 via @physorg_com
Ancient Carnivorous Dread-Possum Is Upending The History Of Mammals | Gizmodo Australia (via @GizmodoAU)  www.gizmodo.com.au/2017/08/ancient-carnivorous-dread-possum-is-upending-the-history-of-mammals/

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روابط التحميل والمشاهدة، الروابط المباشرة للتحميل
او
شاهد هذا الفيديو القصير لطريقة التحميل البسيطة


كيف تحصل على مدونة جاهزة بآلاف المواضيع والمشاركات من هنا
شاهد قناة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على اليوتيوب لمزيد من الشرح من هنا
رابط مدونة منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات في أي وقت حــــتى لو تم حذفها من هنا
شاهد صفحة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على الفيس بوك لمزيد من الشرح من هنا
تعرف على ترتيب مواضيع منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات (حتى لا تختلط عليك الامور) من هنا

ملاحظة هامة: كل عمليات تنزيل، رفع، وتعديل المواضيع الجاهزة تتم بطريقة آلية، ونعتذر عن اي موضوع مخالف او مخل بالحياء مرفوع بالمدونات الجاهزة بآلاف المواضيع والمشاركات، ولكم ان تقوموا بحذف هذه المواضيع والمشاركات والطريقة بسيطة وسهلة. ــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــسلامـ.

[Paleontology • 2017] Owadowia borsukbialynickae • A New Pancryptodiran Turtle from the Late Jurassic of Poland and Palaeobiology of Early Marine Turtles ---ScRaBBlE


 Owadowia borsukbialynickae
Szczygielski, Tyborowski & Błażejowski, 2017


Abstract

Although Western Europe has yielded numerous Jurassic turtle taxa, several represented by cranial material or complete skeletons, the fossil record of the Jurassic turtles remains scarce to the north and east from Germany. Although some Late Jurassic testudinates were historically described from Poland, they were, thus far, represented by fragmentary remains that never were properly figured or described in detail. Therefore, very little is known about the mid-Mesozoic diversity of turtles in that region of the continent. A new pancryptodiran turtle genus and species, Owadowia borsukbialynickae, is described from the uppermost Jurassic (Tithonian, ca. 148 Ma) carbonate sediments of the Kcynia Formation in Owadów-Brzezinki Quarry, near Tomaszów Mazowiecki in central Poland. The lower jaw morphology and palaeoecological setting inhabited by the new genus and species, together with the trophic relationships of the Jurassic pancryptodiran turtles, are discussed in an attempt to determine the potential range of mode of life of O. borsukbialynickae. We propose that the new specimen belongs to a new durophagous pancryptodiran turtle taxon. O. borsukbialynickae might have spent considerable time in the marine environment and specialized on eating hard-shelled invertebrates like bivalves and decapod crustaceans, common to that setting.


Figure 5: Owadowia borsukbialynickae, life restoration during feeding on decapod crustacean.
Digital painting by T. Szczygielski 

SYSTEMATIC PALAEONTOLOGY

Order Testudinata Klein, 1760
Pancryptodira Joyce, Parham, & Gauthier, 2004
Incertae sedis

Genus Owadowia gen. nov.

Type species. Owadowia borsukbialynickae sp. nov.

Etymology. Owadowia, from Owadów-Brzezinki Quarry—the locality where remains of this new turtle were found.
Owadowia borsukbialynickae sp. nov.

Etymology. borsukbialynickae, in honour to the Polish palaeontologist, Prof. Magdalena Borsuk-Białynicka—a long time researcher of the Mesozoic reptiles.

Type specimen. ZPAL V/O-B/1959 (Figures 2-4), stored in the collections of the Institute of Palaeobiology, Polish Academy of Sciences in Warsaw, a fragment of the lower jaw, right coracoid, right ilium, and mostly complete right femur.

Type locality. Owadów-Brzezinki Quarry of Nordkalk GmbH, Sławno, close to Tomaszów Mazowiecki (Central Poland). 

Occurrence. Kcynia Formation, Tithonian, Upper Jurassic; the first lithofacial unit within Zaraiskites zarajskensis subzone.

Diagnosis. Relatively large Jurassic turtle (estimated carapace length around 50 cm) with narrow and V-shaped lower jaw, relatively short and wide but pronounced snout, massive, spoon-like symphysis, no symphyseal hook, well-developed triturating surface in the symphyseal area, moderately developed triturating surface with parallel lingual and labial ridges along the mandibular rami, the labial ridge much higher and sharper than the lingual ridge, the lingual ridge only present laterally and gradually disappearing towards the midline of the symphyseal area, splenial large. The triangular, symmetrical coracoid plate without anterior or posterior expansions, the coracoid neck without coracoid foramen. The slender and proximally and distally slightly curved femur with deep, U-shaped intertrochanteric fossa, small fibular condyle and prominent, well-developed tibial condyle. The ilium with expanded ventral end, constricted neck and well-developed, thin dorsal fan with posterior and no anterior expansion, no signs of sutural attachment to the carapace.


CONCLUSIONS
A new pancryptodiran turtle, Owadowia borsukbialynickae, is described from the Tithonian lagoon limestones of Owadów-Brzezinki Quarry, Poland. The most characteristic trait of this new taxon is its expanded triturating surface indicating a durophagous ecology. The morphology of O. borsukbialynickae mandible is unlike that any other Jurassic turtle known thus far, but rather resembles the Cretaceous protostegids and recent cheloniids, which suggests that this turtle might have inhabited a similar trophic niche. While it is possible that O. borsukbialynickae was a semiaquatic or freshwater turtle, the lower jaw morphology and its inferred feeding preferences make such assumption unlikely, and rather suggest that this animal spent a lot of time in a shallow water, possibly marine environment, like Owadów-Brzezinki lagoons. The taphonomic evidence (the quantitative dominance of marine vertebrates in the Owadów-Brzezinki bone-bed, lack of any brackish and freshwater taxa, and absence of transportation) suggests that O. borsukbialynickae was an inhabitant of these lagoons, rather than a terrestrial animal that inhabited the adjacent land. Such assumptions may be supported in the future by new finds and isotope data.


Tomasz Szczygielski, Daniel Tyborowski and Błażej Błażejowski. 2017. A New Pancryptodiran Turtle from the Late Jurassic of Poland and Palaeobiology of Early Marine Turtles. Geological Journal. DOI: 10.1002/gj.2952

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روابط التحميل والمشاهدة، الروابط المباشرة للتحميل
او
شاهد هذا الفيديو القصير لطريقة التحميل البسيطة


كيف تحصل على مدونة جاهزة بآلاف المواضيع والمشاركات من هنا
شاهد قناة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على اليوتيوب لمزيد من الشرح من هنا
رابط مدونة منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات في أي وقت حــــتى لو تم حذفها من هنا
شاهد صفحة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على الفيس بوك لمزيد من الشرح من هنا
تعرف على ترتيب مواضيع منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات (حتى لا تختلط عليك الامور) من هنا

ملاحظة هامة: كل عمليات تنزيل، رفع، وتعديل المواضيع الجاهزة تتم بطريقة آلية، ونعتذر عن اي موضوع مخالف او مخل بالحياء مرفوع بالمدونات الجاهزة بآلاف المواضيع والمشاركات، ولكم ان تقوموا بحذف هذه المواضيع والمشاركات والطريقة بسيطة وسهلة. ــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــسلامـ.

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