What kind of shellfish are these shells from
When fishing at the Jordanelle reservoir me and my sister found a bunch of these shells on the beach near the Ross creek trailhead. They look cooked and we also found crawfish shells in the same location. As far as I know there are no shellfish in the Jordanelle reservoir so I figure that they were probably brought from somewhere else to cook bit the unusual thin is that each of these shells was a twin shell like the two in the pictures. I've never seen a shell like that before so I got curious about what they were.
Wasatch County Utah
This is not the shell of any of the native or invasive shellfish know in UT, https://extension.usu.edu/waterquality/macrokey/doubleshell/large-clams/. It may have been as you said brought in by something else. From the picture it looks more like an oyster shell than a mussel. Oysters tend to cluster on top of each other. It looks very bleached of color which indicates it was either cooked, or had been sitting in the sun for months. You may want to take it to you local extension office, https://extension.usu.edu/wasatch/ to make sure it isn't a new invasive species. Did you find it near the water at all?
Yeah it was within 3 feet of the water. I'll take it to the extension office like you said but hopefully it was just a shell from someone's meal. Thanks for the response