How a Jaw Fragment From Badlands National Park Became a New Species of Carnivore

One odd jaw fragment was enough to show that a place scientists have studied for 175 years still holds new species. A Park Paleontology News article by a Badlands National Park paleontologist traces how a fossil found during a 2016 survey became the new species Palaeogale evanoffi, from first suspicion to the choice of its name.

Artwork for National Fossil Day 2022. The animal in front is the extinct viverravid Didymictis; the article says Palaeogale might have looked similar.

Why look again at a famous place

The first fossils from the White River Badlands of southwestern South Dakota were documented in 1846, and the White River Chronofauna is among the best-documented fossil-producing areas in the world. After 175 years it is easy to assume nothing new remains, or that an area has been studied enough. The author argues the opposite: a place where others have stopped looking closely is where discoveries are made, because science is never complete.

The animal

The specimen belonged to Palaeogale, a small, linsang-like carnivore and one of the rarest carnivores in any ecosystem it lived in. It first appears in the latest Eocene in Montana and Wyoming, and in the Oligocene and Miocene it ranged across North America and Eurasia: in North America mostly the Great Plains, plus Florida and a recent find in Oregon at John Day Fossil Beds National Monument, and in China, France, Germany and Mongolia. Its fossils are rare and fragmentary: only four specimens have been described from the South Dakota Badlands, and the number of described skulls has not reached double digits, so species are defined by jaw features.

Palaeogale was first thought to be a weasel. Closer study linked it to the extinct viverravids, and a more recent analysis places it at the base of the Feliformia, the group with linsangs, genets and civets and a closer relative of cats than of weasels. That earned it a family of its own, Palaeogalidae.

What looked wrong with the jaw

Every known Palaeogale species has a double-rooted second lower molar, but this jaw had a socket for only one root. The attachment area for the cheek's masseter muscle is normally deep, with a bony lip and sloping down at about 45 degrees; here it was shallow and horizontal, close to the first molar. That suggested something new.

Making sure

Finding nothing in the literature that matched, the author spent as much time as possible in museum collections to compare specimens, drawing on collections in South Dakota, Nebraska and Colorado and the work of a University of Florida collaborator, and spending a week at the American Museum of Natural History in New York, which held specimens from Europe and Asia, a couple of months before the COVID-19 pandemic reached the United States.

Image from the National Park Service's page: the holotype (BADL 64042) in top, side and inner views, from the author's published paper. The arrow marks the single socket for the lower second molar.

How the jaw was found

A seasonal technician on the park's paleontology crew found the fragment during the 2016 summer survey, along with other specimens. The crew was also working to match a binder of 1920 to 1922 photos taken in the Badlands by a Princeton graduate student, to relocate the sites. A university geologist who often does research in the park and has spent years relocating early expedition routes, camps and fossil sites, including from photographs, had proposed the idea to park paleontologists. It paid off in stratigraphic and location data for historically collected specimens, and about 120 of the photos were taken within today's park boundaries. Princeton faculty and students first came to the Badlands in 1882, beginning a long field tradition.

Choosing the name

Species are named for people, places or features; the article's examples are an oreodont named for its collector and a Cretaceous clam named for Sage Creek. Because the crew would likely never have found this specimen without the photo-matching project, the author named the animal for that geologist. The 1920s photographer was an alternative, but an entelodont already carries that name. Reviewers included the park's paleontologist, the NPS senior paleontologist, colleagues at John Day Fossil Beds and a museum in California, and the French specialist who has studied every Palaeogale specimen known by 1981. The paper went to the Proceedings of the South Dakota Academy of Science, the species was registered with ZooBank, and Palaeogale evanoffi became official in early December 2021. The author kept the honoree from learning of it until the paper appeared, and was most proud of his reaction.

Sources

• National Park Service, Badlands National Park, Park Paleontology News, How to Name a New Species from Badlands National Park, by Ed Welsh, paleontologist at Badlands National Park, summarizing his paper in the Proceedings of the South Dakota Academy of Science (2021); the names of crew members, reviewers and the honoree's family, a line drawing modified from a journal figure and photographs of people left out; rewritten in hubnx's own words.