Leptocleidus


Genus

Leptocleidus

Author

Andrews, 1922

Classification

Sauropterygia
Eosauropterygia
Eusauropterygia
Pistosauroidea
Pistosauria
Plesiosauria
Plesiosauroidea
Leptocleididae

Age

Valanginian to Barremian (Lower Cretaceous)

Location

Global distribution: England; South Africa, Australia.

Type species

L. superstes

Other species

L. capensis; L. clemai

Referred material

To compile

Lower Cretaceous plesiosaurs are rare, so Leptocleidus is important because it fills a gap in the fossil record of plesiosaurians. Leptocleidus was once considered to be a late surviving member of the family Rhomaleosauridae but it has recently been reidentified as a close relative of polycotylids. The fossils of all known species of Leptocleidus were preserved in inshore brackish or freshwater deposits. This led Cruickshank (1997) to speculate that the large pliosaurids that appeared during the Middle and Late Jurassic may have outcompeted the rhomaleosaurids in the open ocean and forced them to exploit near-shore niches instead.

There are presently three known valid species of Leptocleidus: L. superstes (the type species), L. capensis, and L. clemai. The genus ‘Peyerus’ was proposed for Leptocleidus capensis by Stromer (1935), but that name is now considered a junior synonym of Leptocleidus (Cruickshank (1997).

L. superstes

Species

L. superstes

Author

Andrews, 1922

Classification

Sauropterygia
Eosauropterygia
Eusauropterygia
Pistosauroidea
Pistosauria
Plesiosauria
Plesiosauroidea
Leptocleididae
Leptocleidus

Age

Barremian, Lower Cretaceous

Formation

Upper Weald Clay

Type location

Sussex, England

Type specimen

NHMUK R4828, skull and partial skeleton

Referred material

To compile

L. capensis

Species

L. capensis

Author

(Andrews, 1911)

Classification

Sauropterygia
Eosauropterygia
Eusauropterygia
Pistosauroidea
Pistosauria
Plesiosauria
Plesiosauroidea
Leptocleididae
Leptocleidus

Age

Uppermost Valanginian, Early Cretaceous

Formation

Sundays River Formation

Type location

Picnic Bush site, overlooking Redhouse Farm, Swartkops River Valley, Cape Province, South Africa

Type specimen

SAM-K5822, a complete skull and partial lower jaw

Referred material

None

L. clemai

Species

L. clemai

Author

Cruickshank and Long, 1997

Classification

Sauropterygia
Eosauropterygia
Eusauropterygia
Pistosauroidea
Pistosauria
Plesiosauria
Plesiosauroidea
Leptocleididae
Leptocleidus

Age

Barremian, Early Cretaceous

Formation

Upper meter of the Birdrong Sandstone

Type location

Near Kalbarri, Carnarvon Basin, Western Australia

Type specimen

WAM 92.8.1-1 to 68, a partial skeleton

Referred material

WAM 94.1.6-1 to 100, a partial skeleton less well preserved than the holotype