Genus: Mauisaurus non HECTOR, 1874 (nomen dubium)
Etymology: In reference to Maui, Moari Demi-god and hero and Greek, sauros, “lizard”: Maui lizard.

Species: gardneri SEELEY, 1877
Etymology:
= Plesiosaurus constrictus OWEN, 1850

Holotype: BMNH 47295

Locality: East Wear Bay, Folkestone, (TR 243366), Kent Island, England, Southern United Kingdom.

Horizon: Lower-Upper Gault.

Biostratigraphy:

Age: Albian Stage, Middle Gallic Subepoch, Uppermost Early Cretaceous Epoch, Early Cretaceous.

Locality: Tooth and vertebrae.

Note: Gastroliths were found.

Referred material:

= Plesiosaurus gardneri (SEELEY, 1877) WHIDBORNE, 1881
Etymology:

Holotype:

Locality: Steyning, Sussex County, England, Southern United Kingdom.

Horizon: Chalk.

Biostratigraphy:

Age: Early Cretaceous.

Material: Anterior cervical vertebrae.

Referred material:

DELAIR, 1959

Locality: Unknown locality in Dorset County, England, Southern United Kingdom.

Horizon:

Biostratigraphy:

Age: Early Cretaceous.

Material:

BMNH 28684: A small immature dorsal centrum.