Photo: National Park Service, Fossil Butte National Monument
- Order
- Myliobatiformes
- Family
- Asterotrygonidae
- Size
- About 22.5 cm / 8.9 in
A Fossil Lake stingray known from embryos through adults, including specimens with young nearby.
As stingrays have cartilaginous skeletons (lacking bones), it is uncommon to find more than their teeth or stings fossilized. Currently, the Fossil Butte Member is the only place in the world where articulated (complete) freshwater stingray fossils have been discovered.
One A. maloneyi specimen was found with several baby stingrays scattered around it and another with an embryo inside. Due to the number of specimens that have been found, from unborn embryos to adults, the life cycles of the ancient species can be studied.
There are almost 200 modern stingray species. Most are bottom-dwellers and feed on bottom-dwelling invertebrates, such as shrimp and crayfish. Stingray fossils are found in association with these invertebrates, indicating their ancient diet was similar to their modern relatives'.
Species text: National Park Service, Fossil Butte National Monument — Fossil Fish Species.