Tooth sleuth: Stingrays!

Have you ever found a stingray mouth plate or pieces of the mouth plate (grinders) before?

A close up of sting ray mouth plates!

A stingray mouth plate refers to the flattened, hard plates inside a stingray’s mouth that are used to crush and grind prey such as mollusks, crustaceans, and small fish. Their mouth plate is made up of rows of modified, fused teeth. This plate functions like a mortar and pestle, allowing stingrays to break down the hard shells of their food through a grinding motion or pounding motion. 

Stingrays shed and replace their mouth plates frequently, much like sharks replace their teeth. On average, stingrays replace mouth plates every few weeks, although this can vary depending on the stingray’s diet, age, and species. Some species may go through several cycles of replacement each year. The process is continuous, with new rows of teeth growing in behind the current ones and gradually moving forward to take their place. This ensures the stingray always has a functional surface ready for feeding.

The pieces of the mouth plate are called grinders and we borrowed and image from this article to show you how the grinders fit into the mouth plate like a piece fitting into a puzzle!

Kerin M. Claeson, Maureen A. O’Leary, Eric M. Roberts, Famory Sissoko, Mamadou Bouaré, Leif Tapanila, David Goodwin, Michael D. Gottfried “First Mesozoic Record of the Stingray Myliobatis wurnoensis from Mali and a Phylogenetic Analysis of Myliobatidae Incorporating Dental Characters,” Acta Palaeontologica Polonica, 55(4), 655-674, (1 December 2010)