Victor Perez

It’s a stingray dental plate, family Myliobatidae.

Looks like a sand tiger shark, likely the genus Carcharias. Can’t really say anything about the age without knowing where it was found.

Hi @charli-higgins, you are in the right ball park in thinking it’s a bullshark. This is an upper tooth from a shark in the genus Carcharhinus. Many species of Carcharhinus have similar teeth, so I don’t think we can say which species unfortunately.

It’s a lower tooth of Hemipristis serra (extinct snaggletooth shark).

Tortoise spur

The first two are pieces of fossil bone that I can’t quite identify. The last photo is of a horse tooth and an astragalus (ankle bone).

It is open-access and you can read it here https://www.tandfonline.com/doi/full/10.1080/02724634.2018.1546732?scroll=top&needAccess=true#metrics-content

Unfortunately, I think this one is a rock, but some photos from other angles could prove me wrong.

I would say more likely than not it is Metaxytherium floridanum, but you can’t be certain from a bone fragment such as this. So your current classification of Dugongidae is the most appropriate.

@matthew-thompson I understand where Jeanette was coming from. Posterior teeth of Megalodon do have a similar appearance to Squalicorax teeth. Here’s an example of a somewhat similar posterior Megalodon tooth https://images.search.yahoo.com/yhs/search;_ylt=AwrExl.Np2ZdzZAAz7c2nIlQ;_ylu=X3oDMTBsZ29xY3ZzBHNlYwNzZWFyY2gEc2xrA2J1dHRvbg–;_ylc=X1MDMTM1MTE5NTcwMgRfcgMyBGFjdG4DY2xrBGNzcmNwdmlkA3NKVU02ekV3TGpKQTUuVmtXXzlhNWdxY01USTRMZ0FBQUFDaUo4MDAEZnIDeWhzLWFyaC0wMDEEZnIyA3NhLWdwBGdwcmlkA01YblpDd2ZiU0hPQVQzRERaUHdFREEEbl9zdWdnAzAEb3JpZ2luA2ltYWdlcy5zZWFyY2gueWFob28uY29tBHBvcwMwBHBxc3RyAwRwcXN0cmwDBHFzdHJsAzQ0BHF1ZXJ5A2Zsb3JpZGElMjBmb3NzaWwlMjBtZWdhbG9kb24lMjB0b290aCUyMHNtYWxsBHRfc3RtcAMxNTY3MDA4Njgw?p=florida+fossil+megalodon+tooth+small&fr=yhs-arh-001&fr2=sb-top-images.search&ei=UTF-8&n=60&x=wrt&type=zxy_2b9e09520896c868dd&hsimp=yhs-001&hspart=arh&param1=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%3D&param2=NGNdNGp6NWVaLZ%3D%3D#id=13&iurl=http%3A%2F%2Fi.ebayimg.com%2Fimages%2Fg%2Fx8oAAOSwLVZVjdlA%2Fs-l300.jpg&action=click

Hi @matthew-thompson , I believe you are correct in your identification as Squalicorax pristodontus. http://elasmo.com/ is a great website to help with identifying shark and ray teeth, and a great resource to learn more about different species.

I agree with Jenn. On a side note, @heath-carroll if you want to mention someone in a comment you need to use the @ symbol before their username rather than the # symbol. I haven’t been getting notifications for your comments.

Hi @james-baxter , your tooth is from the extinct hook-tooth mako, Isurus planus.

Sorry still not a ray. This site will help if you’d like to look at some shark and ray fossils http://elasmo.com/

Well I can say with certainty that it is not a ray. I can’t quite tell from the photo, but it may be a piece of limestone composed of invertebrate fossils. Where did you find it?

Roger says it is most likely the genus Menippe.

I can add myself as the identifier and collector if need be, but otherwise I don’t really have any notes to add.