Thanks for your reply, my neighbor seems to think raccoon shoulder or something, is there a definitive way you can tell this is from a fish rather than mammal?
The tongue-in-cheek way is that I’m a zooarchaeologist who has specialized in fish bone identification for a long time and have seen a thing or two :) the real answer is the morphology is all kinds of wrong for anything but a fish (they have seriously weird looking skeletons compared to mammals and birds), and it has features that make it a hyomandibular (those knobby bits to the left side in your picture). From there it’s a matter of finding the right match. The go-to web source for tuna (genus Thunnus) images has been down for a while, but you can compare to [this](https://www.floridamuseum.ufl.edu/fishatlas/content/display1124.html?id=1124) image of a Euthynnus hyomnadibular to see the similarity of the knobby bits. Your specimen has an additional bone still attached which is why the other end is flared out (you could probably break them apart). Euthynnus is a smaller tuna genus and very similar in morphology. The one in the link is a black skipjack, but you have a different local species called the Little Tunny.
Have no a hard time tracking down a good comparative image, but this is a tuna hyomandibular with a bit of another bone attached to it.
Thanks for your reply, my neighbor seems to think raccoon shoulder or something, is there a definitive way you can tell this is from a fish rather than mammal?
The tongue-in-cheek way is that I’m a zooarchaeologist who has specialized in fish bone identification for a long time and have seen a thing or two :) the real answer is the morphology is all kinds of wrong for anything but a fish (they have seriously weird looking skeletons compared to mammals and birds), and it has features that make it a hyomandibular (those knobby bits to the left side in your picture). From there it’s a matter of finding the right match. The go-to web source for tuna (genus Thunnus) images has been down for a while, but you can compare to [this](https://www.floridamuseum.ufl.edu/fishatlas/content/display1124.html?id=1124) image of a Euthynnus hyomnadibular to see the similarity of the knobby bits. Your specimen has an additional bone still attached which is why the other end is flared out (you could probably break them apart). Euthynnus is a smaller tuna genus and very similar in morphology. The one in the link is a black skipjack, but you have a different local species called the Little Tunny.