by Sarah Boessenecker (@tetrameryx)
Happy Fossil Friday!
This week we take a look at Gavialosuchus americanus.
Gavialosuchus americanus wasn’t actually an alligator; rather, they were more closely related to today’s gharials and crocodiles. Crocodile puns, however, don’t seem to have the same bite as alligator puns.
Gavialosuchus lived in estuaries and coastal environments rather than the freshwater habitats its modern relatives prefer; it also grew quite large, growing in excess of 20 feet. That’s as big as today’s saltwater crocodiles!
Its diet likely consisted of animals commonly found as fossils here in South Carolina, including the Charleston area. These include the dugong Metaxytherium, the river dolphin Pomatodelphis, and shallow water sharks. As Gavialosuchus was a polyphylodont similar to its modern relatives, it was able to constantly replace its teeth throughout its lifetime. Because of this, shed teeth are very commonly found by those hunting for fossils.
Recently, there’s been some controversy about this taxa; some scientists think that it is the same species as a previously named fossil Thecachampsa americana, as well as a handful of other taxa – this just goes to show the more specimens we find of an extinct animal, the larger our data set becomes, and we’re able to piece together better how these animals lived and evolved. Science is always evolving as we learn more!
Erickson, Bruce R.; Sawyer, Glen T. (1996). The estuarine crocodile Gavialosuchus carolinensis n. sp. (Crocodylia: Eusuchia) from the late Oligocene of South Carolina, North America. The Science Museum of Minnesota St. Paul, Minnesota Monograph 3, Paleontology. St. Paul: The Science Museum of Minnesota. pp. 1–47.
Myrick, A.C., Jr. (2001). “Thecachampsa antiqua (Leidy, 1852) (Crocodylidae: Thoracosaurinae) from the fossil marine deposits at Lee Creek Mine, Aurora, North Carolina, USA”. Smithsonian Contributions to Paleobiology 90: 219–225.