Redeskrypcje dinozaurów 2010

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Redeskrypcje dinozaurów 2010

Post autor: d_m »

Barapasaurus to nie euzauropod...
http://dx.doi.org/10.1111/j.1475-4983.2010.00933.x

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nazuul
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Re: Redyskrypcje dinozaurów 2010

Post autor: nazuul »

To, czy Barapasaurus jest euzauropodem czy nie, zaleĹźy od definicji filogenetycznej Eusauropoda. Wg pierwszej zaproponowanej (Salgado et al., 1997) - jest (zob. TaxonSearch).


Teraz z innej beczki - osteologia Magnosaurus:
Benson, R.B.J. (2010) "The osteology of Magnosaurus nethercombensis (Dinosauria, Theropoda) from the Bajocian (Middle Jurassic) of the United Kingdom and a re-examination of the oldest records of tetanurans". Journal of Systematic Palaeontology 8, 131-146. DOI: 10.1080/14772011003603515


Magnosaurus nethercombensis from the Lower Bajocian (Middle Jurassic) of Dorset, UK is a valid species, possessing a single autapomorphy: the presence of anteroposteriorly elongate foramina, inclined anterodorsally and located ventrally on the lateral surface of the dentary. It is the oldest known definite tetanuran dinosaur and shows two tetanuran features: a reduced ischial peduncle of the ilium and the presence of a marked femoral extensor groove. Other records of putative early tetanurans are reviewed: 'Zanclodon cambrensis' from the Rhaetian of Wales; remains from the Norian-Hettangian of Switzerland; Shuvosaurus and Protoavis from the Norian of Texas; Eshanosaurus from the Hettangian of China; theropod remains originally included in the syntype series of Scelidosaurus from the Hettangian-Sinemurian of England; a fragmentary skeleton from the Sinemurian of Italy; Cryolophosaurus from the Sinemurian-Pliensbachian of Antarctica; the partial skeleton of a small theropod from the Toarcian of Morocco; and the lost syntype material of 'Streptospondylus cuvieri' from the Toarcian of Whitby. None of these records can be confidently considered to be the earliest tetanuran record. An early Middle Jurassic age for the earliest-known tetanuran is more consistent with a restricted content of Ceratosauria, comprising Ceratosaurus, Elaphrosaurus, and abelisauroids, than with a wider content including coelophysoids, due to reduction in the length of phylogenetic ghost lineages.
PS Napisałem tu, gdyż: klik.

Opis Magnosaurus z ED zdecydowanie wymaga poprawy. EDIT - gotowe: http://www.forum.dinozaury.com/viewtopic.php?f=6&t=3573


EDIT


Kolejna praca z cyklu hadrozauroidy wg Prieto-Márqueza, tym razem redeskrypcja Gilmoreosaurus mongoliensis:
Prieto-Márquez, A. & Norell, M. (2010) "Anatomy and relationships of Gilmoreosaurus mongoliensis (Dinosauria, Hadrosauroidea) from the late Cretaceous of Central Asia" American Museum novitates 3694, 1-49.

The osteology of the hadrosauroid dinosaur Gilmoreosaurus mongoliensis is redescribed in detail based on the disarticulated cranial and postcranial elements of at least four individuals. These together constitute the lectotype and hypodigm of this species. The diagnosis is emended to include two autapomorphies (paddle-shaped postacetabular process that is less than 70% of the length of the iliac central plate and manual phalanx III-1 with greatly asymmetrical distal surface) and the unique combination of two iliac characters (presence of ischial tuberosity and supraacetabular process with apex located posterodorsal to ischial peduncle). The distinction of G. mongoliensis from B. johnsoni is confirmed on the basis of characters of the maxilla, dentition, ilium, ischium, and pubis. Maximum parsimony analysis places G. mongoliensis as a closely related outgroup to the Hadrosauridae, the sister taxon to the clade composed of all hadrosauroids closer to Telmatosaurus transsylvanicus than to Bactrosaurus johnsoni.

Wcześniej ukazała się też pracka o Rayososaurus:
Carballido, J. L., Garrido, A. C., Canudo, J.I. & Salgado, L. (2010) "Redescription of Rayososaurus agrioensis Bonaparte (Sauropoda, Diplodocoidea), a rebbachisaurid from the early Late Cretaceous of Neuquén" Geobios [w druku. DOI: http://dx.doi.org/10.1016/j.geobios.2010.01.004]

The material belonging to the holotype of Rayososaurus agrioensis Bonaparte is redescribed. The great development of the acromion process, directed in a markedly posterior direction, and the ventral margin of the scapula with a strong ventrodistal expansion, interpreted as autapomorphies of the taxon, justify the validity of the species. Although the material is rather fragmentary, the racquet-shaped scapula, the distal expansion positioned at the same height as the proximal expansion, and the well-developed acromion process allow the taxon to be included within Rebbachisauridae. At the same time, the angle of less than 90̊ between the coracoid articulation and the scapular blade, together with the great development of the acromion process of the scapula, justify its inclusion in a clade situated as a sister group of Cathartesaura. On the basis of the stratigraphic calibration of the phylogenetic analysis, an important diversification event of the rebbachisaurids is deduced during the Hauterivian-Barremian. In this context, the presence of two monophyletic groups, one of which comprises African-European taxa and the other South American taxa, would place the definitive separation of South America and Africa within this time interval.

Czaszka młodego, jeszcze wszystkożernego Dysalotosaurus:
Hübner, T.R. & Rauhut, O.W.M. (2010) "A juvenile skull of Dysalotosaurus lettowvorbecki (Ornithischia: Iguanodontia), and implications for cranial ontogeny, phylogeny, and taxonomy in ornithopod dinosaurs" Zoological Journal of the Linnean Society. DOI: 10.1111/j.1096-3642.2010.00620.x.

A juvenile skull of Dysalotosaurus lettowvorbecki, a basal iguanodontian from the Middle Dinosaur Member (Kimmeridgian) of the Tendaguru Beds (Tanzania), is described and reconstructed in detail. Further preparation and computed tomography scans have uncovered additional and formerly unknown skull elements, especially of the lower jaw. The reconstruction of the skull reveals ontogenetic differences to earlier reconstructions, which were based on specimens of relatively older individuals. The most notable ontogenetic changes in Dysalotosaurus are a relative lengthening of the muzzle, a decrease in the relative size of the orbit, and a straightening of the posterior skull roof. Additionally, ontogenetic variations were found in many single elements of the skull, all of which reflect the three main tendencies described above. Furthermore, there might have been an ontogenetic change in the diet, from omnivorous juveniles to fully herbivorous adults. The results of this study will help to evaluate ontogenetic stages in other ornithopods, and will shed light on a crucial stage of ornithopod evolution that culminated in the highly specialized and diverse hadrosaurs of the Cretaceous. Many of the evolutionary changes seen in this lineage can be attributed to peramorphism, and probably reflect a perfection of the adaptation towards an obligatory herbivorous diet.
Obrazek
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Tomasz Singer
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Re: Redyskrypcje dinozaurów 2010

Post autor: Tomasz Singer »

Według ostatniej rekonstrukcji czaszki Agilisaurus wynika, że ten rodzaj był również wszystkożerny i to w stadium dorosłych, (jeśli nie nawet drapieżnikiem).
Tomasz Singer

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Re: Redyskrypcje dinozaurów 2010

Post autor: Ag.Ent »

Z okazji 100. rocznicy nazwania, specjalne wydanie "Canadian Journal of Earth Sciences" poświęcone albertozaurowi.

+ notka na blogu Andrei Cau.
Tak wiele dinozaurów, tak mało czasu...

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nazuul
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Re: Redyskrypcje dinozaurów 2010

Post autor: nazuul »

Czaszka Saurolophus osborni:
Bell, P.R. "Redescription of the skull of saurolophus osborni brown 1912 ornithischia: hadrosauridae)", Cretaceous Research (2010), doi: 10.1016/j.cretres.2010.10.002

A detailed redescription of the skull of the hadrosaurine Saurolophus osborni based on the three known specimens of this taxon, elucidates for the first time several important aspects of the cranial morphology. Details of the braincase, palate, and nasal crest that were either missed or disputed by previous authors are clarified. The nasal crest is buttressed caudally and caudolaterally by elongations of the frontals and prefrontals, respectively. The unique morphology of the frontals and prefrontals permit differentiation of S. osborni from other hadrosaurs. S. osborni can be differentiated from S. angustirostris by a relatively shorter frontal contribution to the nasal crest, a relatively straight premaxilla in lateral view, a weakly upturned oral margin of the premaxilla, and the absence of a vertical sulcus on the prootic above cranial nerve V. A reassessment of the phylogenetic affinities of S. osborni, exclusive of S. angustirostris, suggests it is most closely related to the Laurasian taxa Prosaurolophus and Kerberosaurus.

W American Museum Novitates (na BioOne) jest trochę nowych danych o Erketu, ale ważniejsza jest dość obszerna analiza kladystyczna i dane, która plasują Qiaowanlong poza Brachiosauridae.
Obrazek
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Re: Redeskrypcje dinozaurów 2010

Post autor: Ag.Ent »

Gdzieś chyba było o tym na forum, ale nie mogę znaleźć, więc wrzucam tutaj: rzecz dotyczy różnej morfologii piór u juwenilnych i dorosłych owiraptorozaurów Similicaudipteryx. Hipoteza ta została zakwestionowana, ale jej autorzy potwierdzają swoją interpretację.
Tak wiele dinozaurów, tak mało czasu...


Ag.Ent
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Re: Redeskrypcje dinozaurów 2010

Post autor: Ag.Ent »

Histologia kości Lirainosaurus astibiae (na razie za darmo, więc zasysajcie :)).
http://dx.doi.org/10.1007/s00114-010-0742-3
Tak wiele dinozaurów, tak mało czasu...

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