''Callawayasaurus'' is a genus of

plesiosaur The Plesiosauria (; Greek: πλησίος, ''plesios'', meaning "near to" and ''sauros'', meaning "lizard") or plesiosaurs are an order or clade of extinct Mesozoic marine reptiles, belonging to the Sauropterygia. Plesiosaurs first appeared ...

from the family

Elasmosauridae Elasmosauridae is an extinct family of plesiosaurs, often called elasmosaurs. They had the longest necks of the plesiosaurs and existed from the Hauterivian to the Maastrichtian stages of the Cretaceous, and represented one of the two groups of p ...

. When the holotype was first described by Samuel Paul Welles in 1962, it was described as ''Alzadasaurus colombiensis'' before being moved into its current genus by Kenneth Carpenter in 1999.Carpenter, K. 1999. "Revision of North American elasmosaurs from the Cretaceous of the Western Interior". ''Paludicola'' 2(2):148-173.

Etymology

''Callawayasaurus'' is named in honor of the paleontologist Jack M. Callaway, editor of ''Ancient Marine Reptiles'' who, as Carpenter put it, "in his brief career as a vertebrate paleontologist, did much to improve our understanding of marine reptiles." The familiar suffix, ''-saurus'' comes from the Greek ' (), meaning "lizard" or "reptile."

Description

''Callawayasaurus'' was a large plesiosaur, with a skull length of , body length of and body mass of . The nares of ''Callawayasaurus'' are elongated and positioned over the maxilla, which has 3-5 teeth. The

neck The neck is the part of the body on many vertebrates that connects the head with the torso. The neck supports the weight of the head and protects the nerves that carry sensory and motor information from the brain down to the rest of the body. In ...

contains 56 vertebrae which are relatively short compared to other elasmosaurids. ''Callawayasaurus''

fossils A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in ...

have no

pectoral bar Pectoral may refer to: * The chest region and anything relating to it. * Pectoral cross, a cross worn on the chest * a decorative, usually jeweled version of a gorget * Pectoral (Ancient Egypt), a type of jewelry worn in ancient Egypt * Pectoralis ...

s; in common with other plesiosaurs such as ''

Terminonatator ''Terminonatator'' (meaning "last swimmer") is a genus of elasmosauridae, elasmosaurid plesiosaur from the Late Cretaceous of Saskatchewan, Canada. It is known from a skull and partial skeleton from a young adult, found in the Campanian-age B ...

''. They also lack postaxial accessory facets. Another nearly complete

skeleton A skeleton is the structural frame that supports the body of an animal. There are several types of skeletons, including the exoskeleton, which is the stable outer shell of an organism, the endoskeleton, which forms the support structure inside ...

was found to be slightly more robust than the holotype

specimen Specimen may refer to: Science and technology * Sample (material), a limited quantity of something which is intended to be similar to and represent a larger amount * Biological specimen or biospecimen, an organic specimen held by a biorepository ...

. This subtle change may indicate sexual dimorphism.

Distribution

The first ''Callawayasaurus'' remains were found in the

Paja Formation Paja may refer to: * Paja, Iran, a village in Sari County * Paja (given name), a Serbian masculine name * Paja (surname) * Paja Formation, geologic formation in Colombia * Paja Brava :''Paja Brava is also used in Spanish speaking countries to ...

near Leiva, Boyaca

Colombia Colombia (, ; ), officially the Republic of Colombia, is a country in South America with insular regions in North America—near Nicaragua's Caribbean coast—as well as in the Pacific Ocean. The Colombian mainland is bordered by the Car ...

. The specific name for the

type Type may refer to: Science and technology Computing * Typing, producing text via a keyboard, typewriter, etc. * Data type, collection of values used for computations. * File type * TYPE (DOS command), a command to display contents of a file. * Ty ...

, "''columbiensis''", means "from Colombia". ''Callawayasaurus'' are known from the

Aptian The Aptian is an age in the geologic timescale or a stage in the stratigraphic column. It is a subdivision of the Early or Lower Cretaceous Epoch or Series and encompasses the time from 121.4 ± 1.0 Ma to 113.0 ± 1.0 Ma (million years ago), a ...

faunal stage of the early Cretaceous period, which extended from 125 to 112 million years ago.

References

External links

Information on plesiosaurs, including images of a ''Callawayasaurus'' skull
{{Taxonbar, from=Q2634949 Elasmosaurids Early Cretaceous plesiosaurs Early Cretaceous reptiles of South America Plesiosaurs of South America Cretaceous Colombia Fossils of Colombia Altiplano Cundiboyacense Paja Formation Fossil taxa described in 1999 Taxa named by Kenneth Carpenter Sauropterygian genera

Etymology

Description

Distribution

See also

References

External links