''Crymocetus'' (meaning "cold sea monster") is an

extinct Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...

genus of

Reptilia Reptiles, as commonly defined, are a group of tetrapods with an ectothermic metabolism and amniotic development. Living traditional reptiles comprise four orders: Testudines, Crocodilia, Squamata, and Rhynchocephalia. About 12,000 living spe ...

from the

Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the more recent of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''cre ...

Chalk Group The Chalk Group (often just called the Chalk) is the lithostratigraphic unit (a certain number of rock strata) which contains the Upper Cretaceous limestone succession in southern and eastern England. The same or similar rock sequences occur ac ...

Sussex Sussex (Help:IPA/English, /ˈsʌsɪks/; from the Old English ''Sūþseaxe''; lit. 'South Saxons'; 'Sussex') is an area within South East England that was historically a kingdom of Sussex, kingdom and, later, a Historic counties of England, ...

England England is a Countries of the United Kingdom, country that is part of the United Kingdom. It is located on the island of Great Britain, of which it covers about 62%, and List of islands of England, more than 100 smaller adjacent islands. It ...

. It is only known from the type species, which is ''C. bernardi''.

Discovery and naming

The holotype consists of a single posterior

cervical vertebra In tetrapods, cervical vertebrae (: vertebra) are the vertebrae of the neck, immediately below the skull. Truncal vertebrae (divided into thoracic and lumbar vertebrae in mammals) lie caudal (toward the tail) of cervical vertebrae. In sauropsid s ...

which was discovered in the

. It was first named as ''

Plesiosaurus ''Plesiosaurus'' (Greek: ' ('), near to + ' ('), lizard) is a genus of extinct, large marine sauropterygian reptile that lived during the Early Jurassic. It is known by nearly complete skeletons from the Lias of England. It is distinguishable by ...

bernardi'' by

Owen Owen may refer to: People and fictional characters * Owen (name), including a list of people and fictional characters with the given name or surname Places United States * Owen, Missouri, a ghost town * Owen, Wisconsin * Owen County, Indiana ...

(1850). However,

Cope A cope ( ("rain coat") or ("cape")) is a liturgical long mantle or cloak, open at the front and fastened at the breast with a band or clasp. It may be of any liturgical colour. A cope may be worn by any rank of the Catholic or Anglican clerg ...

(1869) re-studied the holotype and decided that ''P. bernardi'' warranted its own genus, which he named ''Crymocetus''.E. D. Cope. (1869). On the reptilian orders Pythonomorpha and Streptosauria. ''Proceedings of the Boston Society of Natural History'' 12:251-266 After Cope (1869) was published, nearly all subsequent authors tended to disregard the name ''Crymocetus'', with Lydekker (1889) synonymising ''Crymocetus'' with ''

Cimoliasaurus ''Cimoliasaurus'' was a plesiosaur that lived during the Late Cretaceous (Maastrichtian) of the eastern United States, with fossils known from New Jersey, North Carolina, and Maryland. Etymology The name is derived from the Ancient Greek, Greek ...

''. In any case, ''Crymocetus'' is in need of restudy along with other plesiosaurs from the

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 143.1 to 66 mya (unit), million years ago (Mya). It is the third and final period of the Mesozoic Era (geology), Era, as well as the longest. At around 77.1 million years, it is the ...

deposits of

Classification

(1869) initially classified ''Crymocetus'' within

Elasmosauridae Elasmosauridae, often called elasmosaurs or elasmosaurids, is an extinct family of plesiosaurs that lived from the Hauterivian stage of the Early Cretaceous to the Maastrichtian stage of the Late Cretaceous period (c. 130 to 66 mya). The taxo ...

, while Welles (1962) and Persson (1963)Perrson, P. O., (1963), A revision of the classification of the Plesiosauria with a synopsis of the Stratigraphical and geographical distribution of the Group: ''Lunds Universitets Arksskrift''. N. F. Avd. 2, band 59, n 1, p. 60. instead considered ''Crymocetus'' to be either a member of the

Pliosauridae Pliosauridae is a family of plesiosaurian marine reptiles from the Latest Triassic to the early Late Cretaceous ( Rhaetian to Turonian stages). The family is more inclusive than the archetypal short-necked large headed species that are placed ...

Rhomaleosauridae Rhomaleosauridae is a family of plesiosaurs from the Earliest Jurassic to the latest Middle Jurassic (Hettangian to Callovian stages) of Europe, North America, South America and possibly Asia. Most rhomaleosaurids are known from England, many s ...

. Crymocetus is today classified within

Plesiosaur The Plesiosauria or plesiosaurs are an Order (biology), order or clade of extinct Mesozoic marine reptiles, belonging to the Sauropterygia. Plesiosaurs first appeared in the latest Triassic Period (geology), Period, possibly in the Rhaetian st ...

ia ''

incertae sedis or is a term used for a taxonomy (biology), taxonomic group where its broader relationships are unknown or undefined. Alternatively, such groups are frequently referred to as "enigmatic taxa". In the system of open nomenclature, uncertainty ...

''.

References

{{Taxonbar, from=Q5190491 Late Cretaceous plesiosaurs of Europe Fossil taxa described in 1869 Taxa named by Edward Drinker Cope

Discovery and naming

Classification

See also

References