Polycotylids have been traditionally classified as to be pliosaurs because of their short necks and large heads, but cladistic analyses including a broader suite of anatomical characters
have revealed that they may be plesiosauroids, more closely related to the long-necked elasmosaurids and cryptoclidids than to pliosaurs.
They share a number of features including the elongate rostrum and short postorbital region. They had a worldwide distribution in the Cretaceous Period.
- character 1