Seeleyosaurus
Seeleyosaurus is an extinct genus of plesiosaur that was initially placed within the genus Plesiosaurus in 1895 and was given its own genus in 1940. Two species were known: the type, S. guilelmiimperatoris, and the now obsolete species S. holzmadensis, which has since been absorbed into S. guilelmiimperatoris. It was a relatively small plesiosaur, measuring  long. The holotype is MB.R.1992, a large almost complete skeleton from the Upper Lias (Toarcian) Lias Group Formations of Württemberg, Germany. There seems to be the impression of a rhomboidal flap of skin in a vertical plane; if so, many plesiosaurs may have been equipped in this way. A second specimen (SMNS 12039), preserved in 3D, is the holotype of S. holzmadensis. Classification
The following cladogram follows an analysis by Ketchum & Benson, 2011. Gallery

See also

 List of plesiosaur genera
 Timeline of plesiosaur research

References

Early Jurassic plesiosaurs of Europe
Plesiosauroids
Sauropterygian genera
Fossil taxa described in 1940
Toarcian first appearances