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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 Abelisauridae. Show all posts
Showing posts with label Abelisauridae. Show all posts

Wednesday, March 20, 2019

[Paleontology • 2017] Chenanisaurus barbaricus • An Abelisaurid from the latest Cretaceous (late Maastrichtian) of Morocco, North Africa ---ScRaBBlE


Chenanisaurus barbaricus  
 Longrich, Pereda-Suberbiola, Jalil, Khaldoune & Jourani, 2017  


 Abstract
During the latest Cretaceous, distinct dinosaur faunas were found in Laurasia and Gondwana. Tyrannosaurids, hadrosaurids, and ceratopsians dominated in North America and Asia, while abelisaurids and titanosaurids dominated in South America, India, and Madagascar. Little is known about dinosaur faunas from the latest Cretaceous of Africa, however. Here, a new abelisaurid theropod, Chenanisaurus barbaricus, is described from the upper Maastrichtian phosphates of the Ouled Abdoun Basin in Morocco, North Africa on the basis of a partial dentary and isolated teeth. Chenanisaurus is both one of the largest abelisaurids, and one of the youngest known African dinosaurs. Along with previously reported titanosaurid remains, Chenanisaurus documents the persistence of a classic Gondwanan abelisaurid-titanosaurid fauna in mainland Africa until just prior to the end-Cretaceous mass extinction. The animal is unusual both in terms of its large size and the unusually short and robust jaw. Although it resembles South American carnotaurines in having a deep, bowed mandible, phylogenetic analysis suggests that Chenanisaurus may represent a lineage of abelisaurids that is distinct from those previously described from the latest Cretaceous of South America, Indo-Madagascar, and Europe, consistent with the hypothesis that the fragmentation of Gondwana led to the evolution of endemic dinosaur faunas during the Late Cretaceous.

Keywords: Dinosauria; Theropoda; Ceratosauria; Abelisauridae; Gondwana; Biogeography

Fig. 3. Holotype of Chenanisaurus barbaricus, left dentary OCP DEK-GE 772.
A, lateral view, B, medial view, C, dorsal view.

Abbreviations: gr, vascular grooves; idp, interdental plates; nvf, neurovascular foramina; sd, supradentary bone; sym, symphysis; vas, vascular grooves.
DOI: 10.1016/j.cretres.2017.03.021 

Systematic paleontology
Dinosauria Owen (Owen, 1842)
Saurischia Seeley (Seeley, 1888)

Theropoda Marsh (Marsh, 1881)
Ceratosauria Marsh (Marsh, 1884)

Abelisauridae Bonaparte and Novas (Bonaparte and Novas, 1985)

Chenanisaurus barbaricus new genus and species

Etymology. The genus name refers to the Sidi Chennane phosphate mines, the type locality, and Greek ‘sauros, ‘lizard’. The species name is derived from the Greek barbaros, “savage” or “barbaric” and also refers to Barbary, a name historically used for Morocco and the northwest coast of Africa.

Diagnosis. Large abelisaurid characterized by a proportionately deep mandible, dentary bowed in lateral view, lateral groove and associated foramina located high on dentary; anterodorsal margin of dentary downturned in lateral view; massive symphysis, with anterior margin of symphysis vertical in lateral view; tip of jaws broad, with dentaries meeting at an obtuse angle.

Holotype. OCP DEK-GE 772, anterior end of the left dentary ( Fig. 3 ;  Fig. 4).


Horizon and Locality. The type specimen is reported as coming from the upper Maastrichtian (Couche III) of Sidi Chennane; the pale white color of the bone and the color of the associated matrix are consistent with the preservation seen in other material recovered from this locality. The isolated premaxillary teeth come from the upper Maastrichtian (Couche III) of Sidi Daoui. The maxillary tooth is of unknown provenance but likely comes from either Sidi Chennane or Sidi Daoui. All specimens come from the Ouled Abdoun Basin, Morocco North Africa (Fig. 1).



Fig. 9. Chenanisaurus barbaricus shown to scale with the Couche III titanosaur. 



Nicholas R. Longrich, Xabier Pereda-Suberbiola, Nour-Eddine Jalil, Fatima Khaldoune and Essaid Jourani. 2017. An Abelisaurid from the latest Cretaceous (late Maastrichtian) of Morocco, North Africa. Cretaceous Research. In Press. DOI: 10.1016/j.cretres.2017.03.021

  
             

"Chenanisaurus barbaricus" ....by lythronax-argestes lythronax-argestes.deviantart.com/art/Chenanisaurus-barbaricus-671571810

New moderately-sized abelisaur. I thought the silhouette in the paper was too majungasaurine, so I made my own with blackjack and hookers.
Dentary line drawing from Longrich et al. (2017), silhouette from Rugops by Crizz30 on Commons, human from Andrew Farke on Phylopic as usual.
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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 • 2019] Thanos simonattoi • A New Abelisauridae (Dinosauria: Theropoda) from São José do Rio Preto Formation, Upper Cretaceous of Brazil and Comments on the Bauru Group Fauna ---ScRaBBlE


Thanos simonattoi 
Delcourt & Iori, 2019

 DOI: 10.1080/08912963.2018.1546700 
Art by Deverson da Silva (Pepi).

ABSTRACT
Abelisaurid theropods are well-know from the Cretaceous of several parts of the Southern Hemisphere, including South America, Madagascar, and Africa, but also in India and Europe. Abelisaurids are high-diverse among other theropods with several cervicocephalic specializations reaching medium/large sizes. In the present contribution, we describe a new abelisaurid (Thanos simonattoi, gen. et sp. nov.) from the São José do Rio Preto Formation, Bauru Group, Brazil (Upper Cretaceous). Thanos differs from other theropods by having a well-developed keel becoming wider and deeper posteriorly on the ventral surface; two lateral small foramina separated by a relative wide wall on each lateral surface of the centrum, and well-developed and deep prezygapophyseal spinodiapophyseal fossae. The closed sutures between the axis and odontoid suggest that Thanos had reached a subadult/adult stage before death. Thanos is phylogenetically related to Brachyrostra abelisaurid. The keel on the ventral axial centrum in abelisauroids is here interpreted as a homoplastic condition that became more pronounced towards the phylogeny. The presence of well-developed keel in Thanos suggests that this taxon could be more derived than other abelisaurids. Finally, even though abelisaurids could reach large sizes, Thanos shared the environment with a larger theropod that was probably close to Megaraptora.

KEYWORDS: Theropods, Brachyrostra, vertebra, axis, Thanos simonattoi

Figure 4. An interpretative picture of the paleoenvironment of São José do Rio Preto Formation (Santonian, Upper Cretaceous). The picture shows two specimens of Thanos simonattoi (on the right side) and titanosaur sauropods (on the mid and left sides).
 Art by Deverson da Silva (Pepi).

Systematic palaeontology 
Dinosauria Owen, 1842 
Theropoda Marsh, 1881 
Ceratosauria Marsh 1884 

Abelisauroidea Bonaparte and Novas, 1985 
Abelisauridae Bonaparte and Novas, 1985 

Brachyrostra Canale et al. 2009 

Thanos simonattoi gen. et sp. nov. 

Etymology: Genus name from the Greek thánato, meaning death and from the Marvel’s character Thanos, the Conquer, created by Jim Starlin. Species name in honor of Sérgio Simonatto, the discoverer of the specimen.

.....

Conclusion:
In the present contribution, we have described a new abelisaurid from the São José do Rio Preto Formation, Upper Cretaceous of Brazil. Thanos simonattoi is distinguished from other abelisaurids by having a combination of features: a well-developed keel on the ventral surface becoming wider and deeper posteriorly; two lateral small foramina separated by a relative wide wall and two welldeveloped and deep prezygapophyseal spinodiapophyseal fossae. The keel on the ventral axial centrum of Thanos is interpreted as a homoplastic condition that became more pronounced towards the phylogeny, suggesting that this taxon could be more derived than other abelisaurids. The presence of a medium-sized abelisaurid in the São José do Rio Preto Formation increases the record of theropods, suggesting a complex carnivorous fauna during the Upper Cretaceous of Bauru Group. More findings are needed to better understand the morphology and the internal relationships of Thanos simonattoi.


Rafael Delcourt and Fabiano Vidoi Iori. 2019. A New Abelisauridae (Dinosauria: Theropoda) from São José do Rio Preto Formation, Upper Cretaceous of Brazil and Comments on the Bauru Group Fauna. Historical Biology: An International Journal of Paleobiology. DOI: 10.1080/08912963.2018.1546700 
Méndez AH, Novas FE and Iori FV. 2014. New Record of Abelisauroid Theropods from the Bauru Group (Upper Cretaceous), São Paulo State, Brazil. Revista Brasileira de Paleontologia. 17(1). Citeseer: 23–32.

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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 • 2018] Ceratosaur Palaeobiology: New Insights on Evolution and Ecology of the Southern Rulers ---ScRaBBlE


 The hypothetical phylogenetic relationships of ceratosaurs based on current topologies. 
The main source is from Wang et al. (2016).

Hypothetical reconstruction of two abelisaurids showing the soft tissues on the head inferred from osteological morphology of the skull. On the top, Carnotaurus; on the bottom, PycnonemosaurusArt by Maurilio Oliveira. 

in Delcourt, 2018. 

Abstract
Ceratosaur theropods ruled the Southern Hemisphere until the end of the Late Cretaceous. However, their origin was earlier, during the Early Jurassic, a fact which allowed the group to reach great morphological diversity. The body plans of the two main branches (Noasauridae and new name Etrigansauria: Ceratosauridae + Abelisauridae) are quite different; nevertheless, they are sister taxa. Abelisaurids have lost the ability to grasp in the most derived taxa, but the reduced forelimb might have had some display function. The ontogenetic changes are well known in Limusaurus which lost all their teeth and probably changed the dietary preference at maturity. The results presented here suggest that abelisaurids had different soft tissues on the skull. These tissues might have been associated with evolution of a strong cervicocephalic complex and should have allowed derived taxa (e.g. Majungasaurus and Carnotaurus) to have low-displacement headbutting matches. The ability to live in different semi-arid environment plus high morphological disparity allowed the ceratosaurs to become an evolutionary success.


Figure 1 The hypothetical phylogenetic relationships of ceratosaurs based on current topologies. The main source is from Wang et al. (2016). The phylogenetic position of Chenanisaurus is from Longrich et al.(2016) and the Ligabueino, Austrocheirus, Majungasaurinae and Brachyrostra are from Filippi et al.(2011).

 Figure 4 Skin structures inferred for abelisaurids. Dorsal surface of the skull of (A) Rugops (MNN IGU1), (C) Carnotaurus (MACN-CH 894) and dorsal surface of the fused nasal of (B) Abelisaurus (MPCA 11908). Scales bar: 5 cm. 


Figure 6 Hypothetical reconstruction of two abelisaurids showing the soft tissues on the head inferred from osteological morphology of the skull. On the top, Carnotaurus; on the bottom, Pycnonemosaurus.
Art by Maurilio Oliveira.

Rafael Delcourt. 2018. Ceratosaur Palaeobiology: New Insights on Evolution and Ecology of the Southern Rulers. Scientific Reports. 8, 9730.  DOI:   10.1038/s41598-018-28154-x 

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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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