A genus is a low-level taxonomic rank used in the classification of living and fossil organisms. The taxonomic ranks are domain , kingdom , phylum, class , order , family , genus, and species.... of polycotylid
Polycotylidae
Polycotylidae is a family of plesiosaurs from the Cretaceous, a sister group to the elasmosauridae.With their short necks and large elongated heads, they resemble the pliosaurs, but closer phylogenetical studies indicate that they share many common features with the plesiosauridae and elasmosauridae.... plesiosaur
Plesiosaur
Plesiosaurs were carnivore aquatic reptiles. After their discovery, they were somewhat fancifully said to have resembled , although they had no shell.... , containing one species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring.... , E. muddi. The type specimen was found in Early Cretaceous
Early Cretaceous
The Early Cretaceous or the Lower Cretaceous , is the earlier of the two major divisions of the Cretaceous Period . It began about 146 million years ago.... (late Albian
Albian
Albian is a faunal stage of the Cretaceous geologic timescale.Albian is a term proposed in 1842 by A. d'Orbigny for that stage of the Cretaceous system which comes above the Aptian and below the Cenomanian .... ) rocks in the state of Montana
Montana
Montana is a U.S. state in the Western United States. The western third of the state contains numerous mountain ranges; other 'island' ranges are found in the central third of the state, for a total of 77 named ranges of the Rocky Mountains.... in the USA. At the time, this location was covered by part of the Western Interior Seaway
Western Interior Seaway
The Western Interior Seaway, also called the Cretaceous Seaway, the Niobraran Sea, and the North American Inland Sea, was a huge inland sea that split the continent of North America into two halves during most of the mid and late Cretaceous Period .... .
