Lesson plan
Polycotylidae
Polycotylidae is a family of plesiosaurs from the Cretaceous. Polycotylids first appeared during the Albian stage of the Early Cretaceous, before becoming abundant and widespread during the early Late Cretaceous. Several species survived into the final stage of the Cretaceous, the Maastrichtian, around 72-66 million years ago. The possible latest surviving member Rarosaurus from the late Maastrichtian is more likely a crocodylomorph. With their short necks and large elongated heads, they resemble the pliosaurs, but phylogenetic studies indicate that they are plesiosauroids, being most closely related to Leptocleididae and more distantly to Elasmosauridae. They have been found worldwide, with specimens reported from New Zealand, Australia, Japan, Morocco, the United States, Canada, Eastern Europe, and South America.
Article summary
Polycotylidae is a family of plesiosaurs from the Cretaceous. Polycotylids first appeared during the Albian stage of the Early Cretaceous, before becoming abundant and widespread during the early Late Cretaceous. Several species survived into the final stage of the Cretaceous, the Maastrichtian, around 72-66 million years ago. The possible latest surviving member Rarosaurus from the late Maastrichtian is more likely a crocodylomorph. With their short necks and large elongated heads, they resemble the pliosaurs, but phylogenetic studies indicate that they are plesiosauroids, being most closely related to Leptocleididae and more distantly to Elasmosauridae. They have been found worldwide, with specimens reported from New Zealand, Australia, Japan, Morocco, the United States, Canada, Eastern Europe, and South America.
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Discussion questions
- Summarise the article in your own words. Which single claim would you verify first, and why?
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