Coelophysis Footprints on Long Island? No—Fossils Are in the Southwest

Coelophysis—a slender, Late Triassic theropod (~215–205 Ma)—is known almost exclusively from the Chinle Formation of the American Southwest.

Where Fossils Actually Occur

• Ghost Ranch, New Mexico: The famous Coelophysis bauri bonebed (hundreds of skeletons) discovered 1947 by Edwin Colbert.
• Petrified Forest National Park, Arizona: Additional specimens in the Sonsela Member.
• Other Chinle outcrops: Utah, Colorado, Texas (limited).

Why Not Long Island?

• Geology: Long Island is a Pleistocene terminal moraine (unconsolidated sand, gravel, clay) <20,000 years old—no Triassic bedrock.
• Paleogeography: In the Triassic, the Newark Basin (NJ/NY/CT) hosted related rift-lake deposits, but Coelophysis remains are absent; Grallator tracks (small theropod footprints) occur there instead.
• No published record: No peer-reviewed paper reports Coelophysis bones or tracks from Long Island.

What You Might Be Thinking Of

• Grallator / Eubrontes tracks in the Newark Basin (Rockland County, NY; Hartford Basin, CT/MA).
• Dinosaur footprints at Dinosaur State Park (Rocky Hill, CT) – Eubrontes (likely Dilophosaurus-maker).
• Cretaceous fossils (hadrosaur, mosasaur) in NJ/NY coastal plain deposits—much younger.

If you heard a claim about Coelophysis on Long Island, it is almost certainly a confusion with younger trackways or a different basin.