Turtumus

Turtumus is a genus of extinct marine turtles described from Neogene fossil material. The genus lived in temperate shallow seas during the late Miocene to early Pliocene, roughly seven to three million years ago. The type species is Turtumus inflatus, with a second recognized species, Turtumus pelagicus. The genus is placed in the family Turtinidae within the order Testudines.

Description of known material indicates partial carapaces and limb elements as the primary evidence. The carapace is relatively low and oval to elongated, with estimated lengths of about 60 to 90 cm. Scutes show a distinctive pattern, featuring broadened vertebral areas and narrower costal regions. Limb bones are long and paddle-like, suggesting efficient swimming capabilities suitable for open-coast foraging. The skull is broad with a beak-like rostrum, consistent with a herbivorous to omnivorous diet in marine settings.

Discovery and naming: Fossils were first described in 2022 by paleontologist L. Chen based on specimens recovered from the Coastal Shelf Formation. The generic name Turtumus combines a nod to modern turtles with the common suffix used in reptile genera.

Distribution and paleoecology: Fossil finds come from two temperate coastal sites, indicating a distribution along mid-latitude shelves. Turtumus likely inhabited shallow shelf environments, feeding on seagrasses, algae, and small invertebrates. It coexisted with other marine reptiles and contemporaneous marine mammals.

Significance: The genus contributes to understanding the diversity of Miocene-Pliocene marine turtles and patterns of marine transgression in temperate regions, aiding reconstructions of ancient coastal ecosystems.