Martinectes
| Martinectes Temporal range: Late Cretaceous (late Campanian),  | |
|---|---|
| Skeleton mount, University of Michigan Museum of Natural History | |
| Scientific classification | |
| Domain: | Eukaryota | 
| Kingdom: | Animalia | 
| Phylum: | Chordata | 
| Class: | Reptilia | 
| Superorder: | †Sauropterygia | 
| Order: | †Plesiosauria | 
| Family: | †Polycotylidae | 
| Subfamily: | †Polycotylinae | 
| Clade: | †Dolichorhynchia | 
| Genus: | †Martinectes Clark, O'Keefe & Slack, 2023 | 
| Type species | |
| †Martinectes bonneri Adams, 1997 | |
| Synonyms | |
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Martinectes is an extinct genus of polycotylid plesiosaur from the Late Cretaceous Sharon Springs Formation of the United States. The genus contains a single species M. bonneri, known from multiple skeletons and skulls. Martinectes was historically considered to represent a species of the genus Trinacromerum and later Dolichorhynchops before it was moved to its own genus. It was a large polycotylid measuring around 6–7 metres (20–23 ft) long.