Bull? Dusky? Great White?

[islandfogdoc]

Hello All, 

 

I am new here and trying to identify the species of this tooth that I found in Folly Beach, South Carolina. Does anyone know what species it may be, and would you mind sharing how you came to your conclusion?

 

Thanks!

Sarah

[Fin Lover]

Cropped and brightened...

 

[Fin Lover]

I'm going to say carcharhinus due to the serrations seeming to get smaller towards the tip of the crown, and the root shape. Distinguishing between carcharhinus species can be difficult. Just from looking at pictures of each, I would lean towards bull, but I am by no means confident in my assessment.  Nice size for Folly.

 

[fossilhunter21]

I agree, this looks like it is probably a bull shark tooth. Although I could definitely be wrong, shark teeth can be very tricky to ID. 

 

-Micah

[debivort]

Fin Lover said everything I was thinking. I'd also add that the slight notches in the edges of the crown, marked below, are diagnostic of Carcharinus. Your tooth also looks rather thick through the middle, whereas great white teeth can be rather flat.

 

Bull vs dusky is harder, but dusky teeth often appear quite squat, like they are wider than tall, and can be more asymmetric/backward-facing. There is still variety within Bull and dusky, based on position in the mouth (heterodonty) that makes this challenging. Part of why distinguishing within Carcharinus is hard.

 

 

[Fin Lover]

Thanks @debivort, I meant to also mention the "pinched" look, but forgot. 

[siteseer]

It's a Carcharhinus tooth for sure.  I don't know what you tend to find at Folly Beach nor the age but that's a large tooth for a Carcharhinus and that usually means bull shark, C. leucas, right off the bat.  You find bull shark teeth closer to an inch along the slant in the Late Miocene-Pliocene sediments especially in the Bone Valley Formation..

 

In my experience, dusky shark (C. obscurus) teeth tend to have a less distinct cusp, the cutting edges curving to the tip without forming heels/shoulders, and that cusp is broader when it is clearly present than what you see in the bull shark (the "pinched look" mentioned above).  I remember someone on the Forum saying another distinction is that the nutrient pore is closer to the middle of the root in a dusky but this can be hard to judge on a moderately worn tooth.  Of course, there are going to be teeth, especially smaller ones, in which it looks like it could be either.  You're in the same boat with the rest of us at that point.  Over time, you start siding one way or the other especially as you learn where bulls or duskies occur and don't seem to occur.  It helps to look at modern jaws when you can - photos online or maybe you see some at an aquarium or museum.

 

You can go crazy trying to identify all your Carcharhinus teeth to species.  Modern species are identified by external body features - not their teeth - and most diverged from each other around Late Miocene time so there is overlap in the range of tooth morphology (shapes).  You might separate them now but then resort them 5 years from now and then resort some of them 10 years from now and resort some again 20 years from now.  Your box of question marks might be fuller than the others by then.

 

 

[hemipristis]

Carcharhinus sp., likely bill

[hemipristis]

Just now, hemipristis said:

Carcharhinus sp., likely a I’ll based upon rough symmetry and erectness. As @siteseer noted, dusky teeth tend  to hook towards the posterior nearing the tip

 

[Shellseeker]

18 hours ago, siteseer said:

It's a Carcharhinus tooth for sure.  I don't know what you tend to find at Folly Beach nor the age but that's a large tooth for a Carcharhinus and that usually means bull shark, C. leucas, right off the bat.  You find bull shark teeth closer to an inch along the slant in the Late Miocene-Pliocene sediments especially in the Bone Valley Formation..

Really well said, Jess.. I'll save the description in my Bull_Dusky folder...

 

On your last observation, I can attest to that ... Miocene_Pliocene boundary seems to mean No Megs, a few Makos, and fewer GWs. The Bulls & Dusky teeth are much larger than other locations...

I have speculated that this is true because once the Megs are gone, the Bull and Dusky sharks (Tigers also) live longer and eat better than their ancestors.

 

[Fin Lover]

19 hours ago, siteseer said:

It's a Carcharhinus tooth for sure.  I don't know what you tend to find at Folly Beach nor the age

Folly has a mix, but I typically find mostly smaller teeth there. Lots of lemons, carcharhinus, tigers, sand tigers, and hemis. Hastalis and a partial angy are probably the biggest things I've found, but they do find decent size megs there as well.

[islandfogdoc]

Thank you all so much for your responses, I really appreciate the time y'all took to get back to me and help me with ID. Your descriptions have helped me immensely! Was this just knowledge acquired over time, or is there a specific collection of teeth or book that y'all often reference?

 

@Fin Lover have you ever found goblin shark teeth on Folly? I have a handful that look like either sand tiger or goblin, but I'm not sure how to distinguish between the two (or if it would even make sense to find goblin shark teeth there). 

[Fin Lover]

I am not aware of there being any goblins.

[Meganeura]

2 minutes ago, islandfogdoc said:

Thank you all so much for your responses, I really appreciate the time y'all took to get back to me and help me with ID. Your descriptions have helped me immensely! Was this just knowledge acquired over time, or is there a specific collection of teeth or book that y'all often reference?

 

@Fin Lover have you ever found goblin shark teeth on Folly? I have a handful that look like either sand tiger or goblin, but I'm not sure how to distinguish between the two (or if it would even make sense to find goblin shark teeth there). 

I don't think you get goblins there - just sand tigers.