Trinacromerum
Extinct genus of reptiles
From Wikipedia, the free encyclopedia
Trinacromerum is an extinct genus of sauropterygian reptile, a member of the polycotylid plesiosaurs. It contains two species, T. bentonianum and T. kirki. Specimens have been discovered in the Late Cretaceous fossil deposits of what is now modern Kansas and Manitoba.[1] Some fossils are also found in the Southern United States such as in the Mooreville Chalk of Alabama.[2]
| Trinacromerum Temporal range: Late Cretaceous | |
|---|---|
| |
| Mounted T. kirki cast at the Royal Ontario Museum | |
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Reptilia |
| Superorder: | †Sauropterygia |
| Order: | †Plesiosauria |
| Superfamily: | †Plesiosauroidea |
| Family: | †Polycotylidae |
| Genus: | †Trinacromerum Cragin, 1888 |
| Species | |
| |
Description
Trinacromerum was 3 meters (9.8 feet) long. Its teeth show that it fed on small fish.[1]
The long flippers of Trinacromerum enabled it to achieve high swimming speeds.[1] Its physical appearance was described by Richard Ellis as akin to a "four-flippered penguin."[3] Its name means "three tipped femur".
Classification
Below is a cladogram of polycotylid relationships from Ketchum & Benson, 2011.[4]
