Paleontologists from the University of Kansas have for the first time described a species of Swaindelphys found in Texas’ Big Bend National Park. The new species Swaindelphys solastella is much larger that similar species of Swaindelphys from when it thrived in the Paleocene, though it was still about the size of a modern hedgehog.
Lead Author Kristen Miller is a doctoral student at KU’s Biodiversity Institute and Natural History Museum. She spent a year closely examining specimens collected decades ago by the late Judith Schiebout, a paleontologist who spent her career at Louisiana State University.
Some of the fossils collected at Big Bend by teams led by Schiebout, including molars, had never been thoroughly studied. Miller was hoping to find out what kind of metatherians (a group that includes living marsupials and their extinct relatives) the fossils represented.
“I compared them to a lot of other marsupials from around the same time period to see what they’re most closely related to. It was a lot of morphological comparisons.” – Kristen Miller
Analysis eventually showed that the fossils were members of a surprisingly large species of Swaindelphys. The new species represents the largest marsupial in terms of body size found so far in the North American Paleocene.
“Not only are they the largest metatherians from this time period, but they’re also the youngest and located at the most southern latitude.” – Kristen Miller
