Genus: Cryptocleidus SEELEY, 1892
Etymology: Greek, kryptos, “hidden” and Greek, kleid- (klets), “key, clavicle” + us: Hidden clavicle.
= Apractocleidus SMELLIE, 1916
Etymology: Greek, apraktos, “unfinished, incomplete”, Greek, kleid- (kleis), “key, clavicle”, + us: Incomplete clavicle.
= Crytoclidus GASPARINI & SPALLETTI, 1993 (sic)

Species: eurymerus (PHILLIPS, 1871) SEELEY, 1892
Etymology:
= Plesiosaurus eurymerus PHILLIPS, 1871
= Cimoliosaurus eurymerus (PHILLIPS, 1871) LYDEKKER, 1889
= Plesiosaurus oxfordiensis SEELEY, 1869 (nomen nudum)

Holotype: Lost, formerly in the Woodwardian (=Sedgwick) Museum.

Locality: Bedford, Bedfordshire County, England, Southern United Kingdom.

Horizon: Oxford Clay.

Biostratigraphy:

Age: Callovian Stage, Upper Dogger Epoch, Middle Jurassic.

Material: Limb bone.


Neotype: Natural History Museum, London, England, Southern United Kingdom. NHM R 2860

Locality: From an unspecified brick-pit, Peterborough, Cambridgeshire County, England.

Horizon: Oxford clay.

Biostratigraphy:

Age: Callovian Stage, Upper Dogger Epoch, Middle Jurassic.

Material: Skull is broken and incomplete, basioccipital, exoccipital, opisthotic, supraoccipital, basisphenoid, parietals, frontals, quadrate and squamosal, premaxillae, portions of pterygoids, the mandible is nearly complete, atlas, axis, 30 cervicals, 2 or 3 pectoral, rolex 6200 replica for sale 21 or 22 dorsal, 3 or 4 sacrals, 21 caudals, the distal portion of the tail being wanting, most of the vertebrae have their arches and ribs preserved, in the cervical and caudal regions the ribs in most cases have not yet fused with the centra, the shoulder girdle is complete the fore paddles want some of the phalanges, the pelvis is complete the hind paddles want the proximal end of the right femur, some tarsals, and phalanges.

Referred material:

GLAHM V1799: Scapulocoracoid and left humerus.

Note: Evidence of its front limb being bitten off and healed (ROTHSCHILD, CLARK, & CLARK, 2018).

WINTRICH, JONAS, WILKE, SCHMITZ & SANDER, 2019

IBP R324: Skull and skeleton.

 

BARDET, 1993

Locality: Quarry of Argences, Calvados Department, Normandy, France.

Horizon:

Biostratigraphy:

Age: Callovian Stage, Upper Dogger Epoch, Middle Jurassic.

Material:

Coll. R. Brun, Museum of Le Havre MHNH 1005: Left humerus.

 

BROWN & CRUICKSHANK, 1994

Locality: Dogsthorpe Brick Pit, near Peterborough, (Grid Ref. TF 2130 0217), Cambridgeshire County, England, Southern United Kingdom.

Horizon: Bed 10 of the Lower Oxford Clay.

Biostratigraphy: Kosmoceras jason Zone.

Age: Callovian Stage, Upper Dogger Epoch, Middle Jurassic.

Material:

TETMG R.283.412 (accession number 307/1987): An almost complete skull and associated skeleton.

 

BROWN & KEEN, 1991

Locality: Kellaways Sand of Lincolnshire, Dorset County, England, Southern United Kingdom.

Horizon: Kellaways Formation.

Biostratigraphy:

Age: Lower Callovian Stage, Upper Dogger Epoch, Middle Jurassic.

Material:

SCUNM.P2889: Disarticulated skull bone tentatively identified as the left postorbital, several detached teeth, most of the neck including at least 26 of the 32 centra which should be present, fake hublot big bang watches less than half of the dorsal and sacral vertebrae, 8 out of the total of about 25 caudal vertebrae, an incomplete pectoral girdle, the left femur, and numerous ribs, gastralia and phalanges.

 

CALDWELL, 1997

Locality:

Horizon:

Biostratigraphy:

Age:

Material:

NHMUK PV (old BMNH ) R 2860, 2862:

NHMUK PV (old BMNH ) R 10134:

 

/CHARIG & HORRELL, 1971

Locality:

Horizon:

Horizon:

Biostratigraphy:

Material:

NHMUK PV (old BMNH ) R8575:

 

DELAIR, 1959

Locality: Weymouth, Dorset County, England, Southern United Kingdom.

Horizon: Oxford Clay.

Biostratigraphy:

Age: Callovian Stage, Upper Dogger Epoch, Middle Jurassic.

Material:

Number: Not given: Dorsal vertebrae.

 

= Plesiosaurus oxoniensis PHILLIPS, 1871
Etymology:
= Muraenosaurus oxoniensis (PHILLIPS, 1871) SEELEY, 1874
= Cimoliosaurus oxoniensis (PHILLIPS, 1871) LYDEKKER, 1889

Holotype:

Locality: Long Marston, Oxfordshire County, England, Southern United Kingdom.

Horizon: Oxford Clay.

Biostratigraphy:

Age: Callovian Stage, Upper Dogger Epoch, Middle Jurassic.

Material: Vertebrae, hindlimb and pectoral girdle.

Referred material:

ANDREWS, 1910

Locality: Peterborough, Cambridgeshire County, England, Southern United Kingdom.

Horizon: Oxford Clay.

Biostratigraphy:

Age: Callovian Stage, Upper Dogger Epoch, Middle Jurassic.

Material:

NHMUK PV (old BMNH ) R2431: Parietals, centra of 35 dorsal and caudal vertebrae with a few detached arches, coracoids, right scapula, some bones of the fore paddles, ilium, ischium, portions, of pubes, femur of a very young Individual.

NHMUK PV (old BMNH ) R2420: 3 anterior dorsal vertebrae, 2 middle caudal centra, left humerus, left femur, some odd paddle-bones and portions of ribs.

NHMUK PV (old BMNH ) R2416: Centra of 27 cervical vertebrae, 2 pectorals, 14 dorsals, and 3 caudals, a few of the neural arches and cervical ribs, in all cases free from the centra, the scapulae and coracoids, with the clavicle restored, humeri, radii, ulnae, pubes, ischia, and left femur of a juvenile.

NHMUK PV (old BMNH ) R2417: Skull, the occipital portion and the vassis cranii, mandible, which carried 20-22 teeth on each side, atlas, and axis, 30-31 cervical, 2-3 pectoral, 21-22 dorsals, 3-4 sacrals, and about 21 caudals, neural arches, cervical, dorsal, and caudal ribs, ventral ribs, chevrons, pectoral girdle and fore paddles imperfect, pelvis, and hind paddles imperfect of a juvenile.

NHMUK PV (old BMNH ) R2616: Some cervical vertebrae, mostly with the neural arches, with three just becoming fused to the centra, 1 sacral and 8 caudal vertebrae, the neural arches im most cases missing, nearly prefect shoulder-girdle and pelvis and a few odd paddle-bones.

NHMUK PV (old BMNH ) R2418: 2 cervical vertebrae, 2 pectorals, 18 dorsals, 11 sacrals, and anterior caudals, some portions of dorsal and caudal ribs, the left ilium.

NHMUK PV (old BMNH ) R2862: Basioccipital, part of the basisphenoid, atlas, axis, 28 cervical, 23 pectorals, and dorsals, and 30 sacrals, and caudals, scapulae, coracoids, clavicles, fore paddles wanting only a carpal and some distal phalanges, portions, of ilia, ischia and pubes, hind paddles wanting some distal phalanges, ventral ribs of an old adult.

NHMUK PV (old BMNH ) R3538: A nearly complete and very slightly crushed shoulder-girdle of an adult.

NHMUK PV (old BMNH )R3703: Nearly complete left hind paddle of an adult.

NHMUK PV (old BMNH ) R3705: 14 posterior caudal vertebrae of an adult individual.

NHMUK PV (old BMNH ) R3730: Imperfect skull, atlas, axis and 15 cervical vertebrae, the centra of the posterior caudal vertebrae still united with one another, 6 ribs, left clavicle, radius, ulna, and the greater part of 1 fore paddle, together with a number of odd bones of the other, distal halves of both femora, tibia, fibulae and the greater part of the other bones of both hind paddles.

NHMUK PV (old BMNH) R8621: Lower jaw, 2 teeth and postcranial skeleton.

NHMUK PV (old BMNH ) R2412: 18 cervical vertebrae, with fused arches and ribs, 2 pectorals, a dorsal, 2 sacral and 22 caudal vertebrae, ribs, abdominal ribs, shoulder-girdle somewhat imperfect, especially posteriorly with only portions of the clavicles preserved, right fore paddle, left ulna, incomplete pelvis wanting 1 ilium, hind paddles wanting some tarsals and phalanges.

NHMUK PV (old BMNH ) R2465: Left scpaula of a half-grown individual.

 

= Plesiosaurus durobrivensis SEELEY, 1892
Etymology:

Holotype:

Locality:

Horizon:

Horizon:

Biostratigraphy:

Material:

 

= Muraenosaurus (Cryptoclidus) platymerus SEELEY, 1892
Etymology:
= Cryptocleidus platymerus (SEELEY, 1892) ANDREWS, 1895

Holotype: NHMUK PV (old BMNH ) R2412

Locality: Peterborough, Cambridgeshire County, England, Southern United Kingdom.

Horizon: Oxford Clay.

Biostratigraphy:

Age: Callovian Stage, Upper Dogger Epoch, Late Jurassic.

Material: Incomplete postcranial skeleton.

 

= Apractocleidus teretipes SMELLIE, 1916
Etymology:

Holotype: HMG V1091

Locality: Peterborough, Cambridgeshire County, England, Southern United Kingdom.

Horizon: Oxford Clay.

Biostratigraphy:

Age: Callovian Stage, Upper Dogger Epoch, Late Jurassic.

Material: Fragmentary skeleton.

Referred material:

HMG V1104: Postcranial skeleton.

HMG V1807: Coracoids, scapulae and humeri of an old adult.

HMG V1809: Right forelimb of an old adult.

HMG V1835: Right humerus of an old adult.

_____________________________________________________________________________________

Species: richardsoni (LYDEKKER, 1889) BOGOLUBOV, 1909
Etymology:
= Cimoliosaurus richardsoni LYDEKKER, 1889

Holotype: NHMUK PV (old BMNH ) R6696

Locality: In a brick field between Montevideo House, near Weymouth and Chickerell, Dorset County, England, Southern United Kingdom.

Horizon:

Biostratigraphy: Callovian Stage, Upper Dogger Epoch or Oxfordian Stage, Lower Malm Epoch, Late Jurassic.

Material: 31 cervicals, 19 dorsals, 2 sacrals, 19 caudal vertebrae, pectoral girdle complete, 2 fore and one hind limb, fragmentary pubes, ischia and ilia, radius, ulna, tibia, fibula, carpal and metacarpal bones, several phalanges and ribs.

Referred material:

DELAIR, 1959

Locality: Isle of Portland, Dorset County, England, Southern United Kingdom.

Horizon: Kimmeridge Clay.

Horizon:

Biostratigraphy: Kimmeridgian Stage, Middle Malm Epoch, Late Jurassic.

Material:

NHMUK PV (old BMNH ) R1682:A large humerus, wanting a portion of the shaft.

 


Locality: Isle of Portland, Dorset County, England, Southern United Kingdom.

Horizon: Portland Oolite.

Biostratigraphy:

Age: Middle Tithonian Stage, Upper Malm Epoch, Late Jurassic.

Material:

Number: Not given: Fragments.

 

LYDEKKER, 1889

Locality: Isle of Portland, Dorset County, England, Southern United Kingdom.

Horizon: Portland Oolite.

Biostratigraphy:

Age: Middle Tithonian Stage, Upper Malm Epoch, Late Jurassic.

Material:

NHMUK PV (old BMNH ) R1683: The centrum of a caudal vertebra.

 


Locality: Near Peterborough, tag grand carrera calibre 17 replica Cambridgeshire County, England, Southern United Kingdom.

Horizon: Oxford Clay.

Biostratigraphy:

Age: Callovian Stage, Upper Dogger Epoch, Late Jurassic.

Material:

NHMUK PV (old BMNH ) R1669: A left humerus.

 


Locality: England, Southern United Kingdom.

Horizon: Kimmeridge Clay.

Biostratigraphy:

Age: Kimmeridgian Stage, Middle Malm Epoch, Late Jurassic.

Material:

NHMUK PV (old BMNH ) R1670: An associated left radius and ulna.