Category «Plesiosauria»
Styxosaurus
The holotype specimen (KUVP 1301) of Styxosaurus is an articulated skull and anterior portion of the neck. It was found in the Niobrara Chalk near Hell Creek, Logan County, Western Kansas in 1890. It was described later that year as a new species Cimoliosaurus snowii by Williston (1890a) (and Williston 1890b), who subsequently (Williston 1906) referred the species to Elasmosaurus.
Borealonectes
Under construction
Thaumatodracon
Thaumatodracon is a relatively large rhomaleosaurid from the Lower Jurassic (Sinemurian) of Lyme Bay – the coast between Lyme Regis and Charmouth – UK. The holotype specimen (NLMH 106.058) is an almost complete skull and cervical (neck) series.
Avalonnectes
Avalonnectes is a small-bodied basal rhomaleosaurid. Avalonnectes was named by Benson, Evans and Druckenmiller (2012) for a partial skeleton including the rear part of the skull from the lowermost Jurassic of Street, Somerset, UK. The specimen (NHMUK PV OR 14550) was previously referred to Thalassiodracon hawkinsii and is one of many historical plesiosaur skeletons preserved on slabs on display in the Natural History Museum, London.
Eurycleidus
Under construction
Ogmodirus
The type skeleton of ‘Ogmodirus’ was collected in 1909 by C. Boyce from the upper Greenhorn Limestone Formation (Lower Turonian, Late Cretaceous) of Cloud County (near Aurora), Kansas (Storrs 1999, Schumacher and Everhart 2005). The specimen, KUVP 441, is a partial skeleton consisting of partial vertebral column (51 cervical vertebrae, 18 caudal vertebrae), limb, and girdle elements.
Maresaurus
M. coccai (Gasparini 1997) type material: MOZ 4386 V articulated skull and mandible, atlas-axis and first cervical vertebrae. From the upper part of the Los Molles Formation, Cuyo Group, Emileia giebeli and Emileia multiformis subzone.
Skull of Maresaurus in lateral, dorsal and ventral view.