Callawayasaurus

Callawayasaurus is a genus of plesiosaur from the family Elasmosauridae. When the first "Callawayasaurus" fossil was first discovered by Samuel Paul Welles in 1962, it was described as "Alzadasaurus colombiensis" before being moved into its current genus by Kenneth Carpenter in 1999.
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.
The first skull of "Callawayasaurus" to be found was long, while the animal as a whole grew up to long. The nares of "Callawayasaurus" are elongated and positioned over the maxilla, which has 3-5 teeth.
The neck contains 56 vertebrae which are relatively short compared to other elasmosaurids. "Callawayasaurus" fossils have no pectoral bars; in common with other plesiosaurs such as "Terminonatator". They also lack postaxial accessory facets.
Another nearly complete skeleton was found to be slightly more robust than the holotype specimen. This subtle change may indicate sexual dimorphism.
Distribution.
The first "Callawayasaurus" remains were found in the Paja Formation near Leiva, Boyaca Colombia.
The species name for the type, "columbiensis", means "from Colombia".
"Callawayasaurus" are known from the Aptian faunal stage of the early Cretaceous period, which extended from 125 to 112 million years ago.