A new leptocleidid (Sauropterygia, Plesiosauria) from the Vectis Formation (Early Barremian–early Aptian; Early Cretaceous) of the Isle of Wight and the evolution of Leptocleididae, a controversial clade

  title={A new leptocleidid (Sauropterygia, Plesiosauria) from the Vectis Formation (Early Barremian–early Aptian; Early Cretaceous) of the Isle of Wight and the evolution of Leptocleididae, a controversial clade},
  author={Roger B. J. Benson and Hilary F. Ketchum and Darren Naish and Langan E. Turner},
  journal={Journal of Systematic Palaeontology},
  pages={233 - 250}
Among the most enigmatic and controversial plesiosaurian clades is the Early Cretaceous Leptocleididae, a small group of (mostly) short-necked taxa with ‘intermediate' or ‘pliosauromorph' body proportions. Leptocleidids have often been interpreted as basal members of Pliosauroidea, and their presence in marginal marine and even freshwater facies has led to suggestions that they might represent late-surviving relicts, perhaps related to the Lower Jurassic rhomaleosaurids. We describe a new… 

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

ABSTRACT Plesiosauria 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

A new elasmosaurid plesiosaurian from the Early Cretaceous of Russia marks an early attempt at neck elongation

A new elasmosaurid is described from the upper Hauterivian (Lower Cretaceous) of Ulyanovsk (European Russia) and its shape suggests multiple episodes of elongation and shortening, however, the precise patterns are obscured by an unstable phylogenetic signal.

Taxonomic reassessment of Hydralmosaurus as Styxosaurus: new insights on the elasmosaurid neck evolution throughout the Cretaceous

  • R. Otero
  • Biology, Environmental Science
  • 2016
This research recognizes the ‘Cimoliasauridae’ (nomen dubium) as a paraphyletic group but informative of a plesiomorphic cervical vertebral morphology of elasmosaurids which was persistent throughout the whole Cretaceous and from whom aristonectines, styxosaurines and Thalassomedon and close relatives are derived.

A rare new Pliensbachian plesiosaurian from the Amaltheenton Formation of Bielefeld in northwestern Germany

Sachs, S. & Kear, B.P. November 2018. A rare new Pliensbachian plesiosaurian from the Amaltheenton Formation of Bielefeld in northwestern Germany. Alcheringa 42, 487-500. ISSN 0311-5518. We describe

Reassessment of 'Plesiosaurus' megacephalus (Sauropterygia: Plesiosauria) from the Triassic-Jurassic boundary, UK

The holotype specimen of ‘Plesiosaurus’ megacephalus Stutchbury, 1846 (BRSMG Cb 2335) was destroyed in an air raid on Bristol during WWII. The specimen comprised a complete skeleton from the

Osteology of Rhomaleosaurus Thorntoni (Sauropterygia: Rhomaleosauridae) from the Lower Jurassic (Toarcian) of Northamptonshire, England

ABSTRACT This paper describes the holotype of Rhomaleosaurus thorntoni (NHMUK PV R4853) from the upper part of the Whitby Mudstone Formation (Toarcian) of Kingsthorpe Hollow, Northamptonshire,

The Anatomy of Stratesaurus (Reptilia, Plesiosauria) from the Lowermost Jurassic of Somerset, United Kingdom

One of the oldest plesiosaurians, Stratesaurus taylori from the earliest Hettangian of the United Kingdom, is provided, due to its plesiomorphic morphology and well-characterized anatomy, to be recommended as an ingroup representative of Plesiosauria for future cladistic analyses of Triassic sauropterygians.

The forgotten remains of a leptocleidid plesiosaur (Sauropterygia: Plesiosauroidea) from the Early Cretaceous of Gronau (Münsterland, Westphalia, Germany)

  • O. Hampe
  • Geology
    Paläontologische Zeitschrift
  • 2013
Gronausaurus wegneri n. gen. n. sp. represents a newly discovered leptocleidid sauropterygian based on one individual from the Early Cretaceous (Berriasian) of Gronau in Westphalia, Germany. The



Reassessment of the Lower Cretaceous (Barremian) pliosauroid Leptocleidus superstes Andrews, 1922 and other plesiosaur remains from the nonmarine Wealden succession of southern England

To test the competing hypotheses, L. superstes together with all closely related species were rescored into the most comprehensive published phylogenetic data sets of Plesiosauria and Pliosauroidea and confirmed placement within either Rhomaleosauridae sensu stricto, or a discrete ‘leptocleidoid’ clade.

A new pliosaurid (Sauropterygia, Plesiosauria) from the Oxford Clay Formation (Middle Jurassic, Callovian) of England: evidence for a gracile, longirostrine grade of Early-Middle Jurassic pliosaurids

A partial skeleton from the Sigiloceras enodatum ammonite Subzone (lower Callovian, Middle Jurassic) of the Oxford Clay Formation of Quest Pit, near Stewartby, Bedfordshire, UK, represents one of the

A phylogeny of Plesiosauria (Sauropterygia) and its bearing on the systematic status of Leptocleidus Andrews, 1922

A cladistic analysis including Leptocleidus and a new, apparently morphologically similar specimen from Alberta, was undertaken to assess their phylogenetic position within Plesiosauria, and results indicate a basal dichotomous split into the traditionally recognized pliosauroidea and plesiosauroid clades.

The Anatomy and Taxonomy of Macroplata tenuiceps (Sauropterygia, Plesiosauria) from the Hettangian (Lower Jurassic) of Warwickshire, United Kingdom

ABSTRACT A detailed re-description and revised diagnosis is given for Macroplata tenuiceps Swinton, 1930, a plesiosaurian known from a single almost complete specimen (BMNH R5488) from the Blue


The new taxon was a specialized surface swimmer with a stiffened trunk and large forelimbs, occurring in the gap between the late Anisian pistosaurids and the earliest Rhaetian plesiosaurs.

Cranial Anatomy of Thalassiodracon hawkinsii (Reptilia, Plesiosauria) from the Early Jurassic of Somerset, United Kingdom

The relatively long neck and small skull of Thalassiodracon indicate that the robust skeleton and macropredaceous habits of rhomaleosaurids and pliosaurids were derived independently.

A new pistosaurid (Reptilia: Sauropterygia) from the Middle Triassic of Nevada and its implications for the origin of the plesiosaurs

ABSTRACT We describe a new pistosaurid sauropterygian, Augustasaurus hagdorni, gen. et sp. nov., from the Middle Triassic of Nevada. The specimen was collected in Muller Canyon, Augusta Mountains,


A phylogenetic analysis places Plesiopterys as the sister group of the Plesiosauroidea, and as such the taxon is the most basal taxon yet known on the branch leading to this major clade.

A Cladistic Analysis and Taxonomic Revision of the Plesiosauria (Reptilia: Sauropterygia)

The Plesiosauria is found to by polyphyletic due to the inclusion of the Polycotylidae; this second clade is instead a member of the Plesiosauroidea, and thus more closely related to elasmosaurs than to other ‘pliosaurs’.

a new elasmosaurid plesiosaur from the Lower Jurassic of southern France

Plesiosaurus tournemirensis Sciau, Crochet and Mattei, based on a nearly complete skeleton with skull from the Upper Toarcian (Lower Jurassic) of Tournemire (Aveyron Department, southern France), is