Results 11 to 20 of about 90 (69)

A New Elasmosaurid (Sauropterygia, Plesiosauria) From the Bearpaw Shale (Late Cretaceous, Maastrichtian) of Montana Demonstrates Multiple Evolutionary Reductions of Neck Length Within Elasmosauridae

Journal of Vertebrate Paleontology, 2017
ABSTRACTPlesiosauria is a diverse clade of marine reptiles that have been studied since the early 19th century. However, phylogenetic relationships within the group have been contentious due to limited taxon sampling and a misunderstanding of how ontogeny and interspecific and intraspecific variation affect character states.
Patrick S. Druckenmiller, Roger B.J. Benson   +1 more
exaly   +2 more sources

CT-scan description of Alexandronectes zealandiensis (Elasmosauridae, Aristonectinae), with comments on the elasmosaurid internal cranial features

Journal of Vertebrate Paleontology, 2021
The holotype specimen of Alexandronectes zealandiensis is analyzed using digital reconstruction based on CT scans. Additional information regarding internal anatomy or obscured details are added. Additional features include: ectopterygoid rhombic in shape with posterior end pointed, a feature shared only with Aristonectes quiriquinensis; pterygoid ...
Jose P. O'Gorman, Rodrigo A. Otero, Norton Hiller, Robin F. O'Keefe, R. Paul Scofield, Ewan Fordyce   +5 more
openaire   +4 more sources

Osteology of a perinatal aristonectine (Plesiosauria; Elasmosauridae) [PDF]

Antarctic Science, 2016
AbstractPerinatal specimens give valuable information about the first stages of vertebrate ontogeny. Here, the morphology and palaeohistology of an aristonectine perinatal specimen from Seymour Island (Isla Marambio), López de Bertodano Formation are analysed.
O'gorman, Jose Patricio, Talevi, Marianella, Fernández, Marta Susana   +2 more
openaire   +2 more sources

The oldest plesiosaur (Reptilia, Sauropterygia) from Antarctica [PDF]

Polar Research, 2011
Antarctic plesiosaurs are known from the Upper Cretaceous López de Bertodano and Snow Hill Island formations (Campanian to upper Maastrichtian), which crop out within the James Ross Basin region of the Antarctic Peninsula.
Alexander Wilhelm Armin Kellner, Tiago Rodrigues Simões, Douglas Riff, Orlando Grillo, Pedro Romano, Helder de Paula, Renato Ramos, Marcelo Carvalho, Juliana Sayão, Gustavo Oliveira, Taissa Rodrigues   +10 more
doaj   +1 more source

Postcranial morphology of Aristonectes (Plesiosauria, Elasmosauridae) from the Upper Cretaceous of Patagonia and Antarctica

Antarctic Science, 2012
AbstractA partial, postcranial skeleton of a juvenile individual referred to Aristonectes cf. parvidens from the upper Maastrichtian López de Bertodano Formation, Isla Marambio (Seymour Island), Antarctica, is described. Additionally, two juvenile specimens, also referred to A. cf. parvidens from the Allen Formation (upper Campanian–lower Maastrichtian)
O'gorman, Jose Patricio, Brandoni, Zulma Nelida, Salgado, Leonardo   +2 more
  +6 more sources

Vegasaurus molyi, gen. et sp. nov. (Plesiosauria, Elasmosauridae), from the Cape Lamb Member (lower maastrichtian) of the Snow Hill Island Formation, Vega Island, Antarctica, and remarks on Wedellian Elasmosauridae

Journal of Vertebrate Paleontology, 2015
ABSTRACT—A new elasmosaurid, Vegasaurus molyi, gen. et sp. nov., from Vega Island, James Ross Archipelago, Antarctica, is described. The holotype and only specimen of this species (MLP 93-I-5-1) was collected from the lower Maastrichtian Cape Lamb Member of the Snow Hill Island Formation.
O'gorman, Jose Patricio, Salgado, Leonardo, Olivero, Eduardo Bernardo, Marenssi, Sergio Alfredo   +3 more
openaire   +2 more sources

A basal elasmosaurid plesiosaur from the upper Albian– lower Cenomanian? Cambridge Greensand

Acta Palaeontologica Polonica
An historical indeterminate elasmosaurid specimen CAMSM X50356 (CAMSM = Sedgwick Museum) collected during the 19th century is described. The specimen comes from the Cenomanian Cambridge Greensand although the possibility of an Albian–lower Cenomanian age
Jose P. O’Gorman, Roger B.J. Benson
doaj   +1 more source

New Insights on theAristonectes parvidens(Plesiosauria, Elasmosauridae) Holotype: News on an Old Specimen

Ameghiniana, 2016
Abstract. New observations on the holotype of the Maastrichtian aristonectine elasmosaurid Aristonectes parvidens Cabrera from Chubut Province, Argentina, reveals features that were not previously described while resulting in new interpretations. Quantitative comparison with non-aristonectine elasmosaurids demonstrates that the increase in the number ...
openaire   +2 more sources

How Elongated? The Pattern of Elongation of Cervical Centra of Elasmosaurus platyurus with Comments on Cervical Elongation Patterns among Plesiosauromorphs

Diversity
Elasmosaurids comprise some of the most extreme morphotypes of plesiosaurs. Thus, the study of their neck and vertebrae elongation patterns plays a crucial role in understanding the anatomy of elasmosaurids.
José Patricio O’Gorman
doaj   +1 more source

Elasmosauridae

, 2019
Published as part of Sassoon, Judyth, 2019, Congenital and late onset vertebral fusions in long necked plesiosaurs: The first report of spondylosis deformans in Sauropterygians, pp. 1-15 in Palaeontologia Electronica (1 A) (1 A) 22 (1) on pages 4-6, DOI: 10.26879/913, http://zenodo.org/record ...
openaire   +2 more sources