Meripetopsis

Meripetopsis is a genus of extinct marine reptiles belonging to the clade Sauropterygia, which includes plesiosaurs and their relatives. Fossil remains of Meripetopsis have been discovered in marine sediments dating to the Late Jurassic period, approximately 160 to 150 million years ago. The genus is known primarily from the Oxfordian and Kimmeridgian stages of the Middle to Late Jurassic epoch, with fossils found in regions that are now parts of Europe and North America.

The name *Meripetopsis* derives from Greek, with *meri* meaning "part," *petra* meaning "rock," and *opsis* meaning "appearance," referencing the fragmented nature of the fossils initially described. Meripetopsis is distinguished by its elongated neck and relatively small skull, features that suggest it may have been an early or basal member of the Plesiosauria clade. Unlike later, more specialized plesiosaurs, Meripetopsis appears to have retained some primitive traits, such as a broader body and shorter limbs, indicating a transitional form between earlier sauropterygians and more advanced plesiosaurs.

Fossil evidence of Meripetopsis includes partial skeletons, particularly limb bones and vertebrae, which provide insights into its anatomy. The species is thought to have been a moderately sized marine reptile, likely adapted to a pelagic lifestyle, though its exact diet and behavior remain speculative. Meripetopsis is often studied alongside other contemporaneous marine reptiles, such as *Pliosaurus* and *Steneosaurus*, to understand the evolutionary diversification of Jurassic marine ecosystems.

Meripetopsis is significant in paleontology as an example of the gradual morphological changes that occurred within Sauropterygia during the Jurassic period. Its fossils contribute to the understanding of how early plesiosaurs adapted to life in the oceans, bridging the gap between earlier, more generalized sauropterygians and the highly specialized forms that dominated the Mesozoic seas.