Named By: Roger B. J. Benson, Mark Evans & Patrick S. Druckenmiller - 2012.
Classification: Chordata, Reptilia, Sauropterygia, Plesiosauria, Rhomaleosauridae.
Species: S. taylori (type).
Size: Skull 18 centimetres long.
Known locations: England - Blue Lias Formation.
Time period: Hettangian of the Jurassic.
Fossil representation: Skull and partial post cranial skeleton.
Stratesaurus represents a genus of rhomaleosaurid plesiosaur, a type of plesiosaur noted for having a shorter neck and proportionately larger head than other plesiosaurs, though not to the extent of pliosaurs. The discovery of Stratesaurus in Hettangian aged rocks means that individual Stratesaurus were swimming in European waters near the Triassic/Jurassic boundary, which in turn indicates that Stratesaurus were amongst the first known plesiosaurs, marine reptiles that do not appear in great numbers until slightly later in the Jurassic.
- High Diversity, Low Disparity and Small Body Size in Plesiosaurs (Reptilia, Sauropterygia) from the Triassic–Jurassic Boundary - PLoS ONE 7 (3): e31838 - Roger B. J. Benson, Mark Evans and Patrick S. Druckenmiller - 2012.