Carbonemys

Carbonemys cofrinii is an extinct giant podocnemidid turtle known from the Middle Paleocene Cerrejón Formation of the Cesar-Ranchería Basin in northeastern Colombia. The formation is dated at around 60 to 57 million years ago, starting at about five million years after the KT extinction event.

Discovery and Naming
In 2005, the holotype specimen was discovered in the Cerrejón coal mine by a North Carolina State University doctoral student named Edwin Cadena. The genus name translates to "Coal Turtle" ("Carbon" Latin for "coal" and "emys" Greek for "freshwater turtle"), in reference to the coal mine the fossil was extracted from. The specific epithet honors Dr. David Cofrin.

Description
The Carbonemys holotype had a shell that measured about 1.72 m and estimated at 1.8 m for complete carapace. This would make it one of the world's largest turtles, tied with the Quaternary Peltocephalus maturin and Eocene Drazinderetes in carapace length and only outsized by the Cretaceous protostegids, the Miocene Stupendemys, and two Quaternary testudines (Megalochelys and Titanochelon).

Paleobiology
Carbonemys’ relatively massive jaws indicate that it had a powerful bite. It was likely an omnivore, consuming plants and mollusks as well as smaller reptiles, which were diverse and abundant in its neotropical freshwater habitat. Its cohabitants included other turtles like the smaller podocnemid Cerrejonemys, the giant boid (constrictor) Titanoboa, and crocodylomorphs such as the dyrosaurids Cerrejonisuchus, Acherontisuchus, and Anthracosuchus.