A few Miocene shark teeth for id please

[Ludwigia]

There are a couple of sites in the early Miocene Burdigalian not too far away at all from my home, so often when I take a tour on my bike I head off to one of them and scratch around in the gravelly sands with a pocket knife for a couple of hours in search of shark teeth. They come from practically the same time frame as some of the ones at Calvert Cliffs. I've already posted a few things from these sites here in the Forum in the past. I've been putting down most of the finds simply as Carcharias sp. and leaving it at that, but lately I've been wanting to get a bit more specific, which is the reason for this post. I'd like to show some pics and ask you experts if you think my guesses are correct or if I'm completely off base. Please imagine a question mark beside the names

 

1. Carcharias cuspidata. 18mm.

 

 

2. I'm stumped on this one. 12mm.

 

 

3. Carcharias acutissima. The longest being 22mm.

 

 

4. Odontaspis reticulata. 12mm.

 

 

5. Also unsure. The longest is 13mm.

 

 

6. The top 2 Carcharhinus brachyurus 8mm. Not sure about the other two.

 

Thanks in advance for your suggestions.

 

[Tidgy's Dad]

No idea, but nice finds! 

[Jazfossilator]

I can’t help either, but Nice teeth indeed!  

[Miocene_Mason]

The one stumping you is a partial cow shark I believe. Probably bluntnose sevengill (at least the odds are).

[Al Dente]

2 minutes ago, WhodamanHD said:

The one stumping you is a partial cow shark I believe. Probably bluntnose sevengill (at least the odds are).

I agree, probably Notorhynchus.

[Ludwigia]

1 hour ago, WhodamanHD said:

The one stumping you is a partial cow shark I believe. Probably bluntnose sevengill (at least the odds are).

 

1 hour ago, Al Dente said:

I agree, probably Notorhynchus.

Ah, neat! Thanks guys. I haven't found one of those at these sites yet. This would be an upper then, correct?

[Ludwigia]

2 hours ago, Tidgy's Dad said:

No idea, but nice finds! 

 

1 hour ago, Jazfossilator said:

I can’t help either, but Nice teeth indeed!  

Glad you like them, fellas But I still sure would like to get some more specifics on the others.

[Miocene_Mason]

54 minutes ago, Ludwigia said:

 

Ah, neat! Thanks guys. I haven't found one of those at these sites yet. This would be an upper then, correct?

Actually I think lower, what say you @Al Dente?

[Max-fossils]

Nice teeth Roger! 

@WhodamanHD @Ludwigia I don't think it's possible to tell whether the tooth is upper or lower, it's too incomplete. And this image (from fossilguy.com ) shows that it could be either. Shame it's broken, would've been a nice one otherwise!

 

For the other teeth, this is what I would say:

• #1 could be C. cuspidata, but it might also be another (like C. acutissima). But most likely in the Carcharias genus. 
• Then for #3, the left one is too hard to tell because it's incomplete (and we can't tell if it had cusps or not). The right one, I'm not sure from the photo's whether the tooth is meant not to have cusps, or if they just got worn off. If it doesn't have cusps (and wasn't meant to) then it wouldn't be a Carcharias. Maybe something like Isurus oxyrinchus? Not sure...
• I don't think #4 is Odontaspis reticulata, as that species frequently seems to have cusps, which your teeth lack. It's some other kind of (sand tiger?) shark, but which one I can't tell
• I think #5 could be Carcharodon hastalis (not the front teeth, but more towards the posterior)? Again very worn which makes it difficult to tell...
• The ones in #6 are out of my league for my limited knowledge...

It's a shame that the teeth are so worn, because that's what is making ID so much more difficult...

But (although the colors aren't very visible on your teeth, I'm saying this due to the variability in shades of grey ) the preservation and colors look very similar to the Eocene teeth of Balegem in Belgium. Perhaps the sediment type is very similar, making the fossilization processes also similar (and hereby giving similarly-looking shark teeth)?

 

Nice to see that you were out hunting for shark teeth, must have been a big change from the ammonites, no?  

 

Best regards,

 

Max

[Miocene_Mason]

12 minutes ago, Max-fossils said:

don't think it's possible to tell whether the tooth is upper or lower, it's too incomplete. And this image (from fossilguy.com ) shows that it could be either. Shame it's broken, would've been a nice one otherwise!

My reasoning is that if you look closely (magnified below) the blade has two cusps on it whereas uppers usually only have one. I don’t think the photo you provided has them arranged as lowers on bottom and uppers on top. But I could be wrong, The only Cows I’ve found are lowers.

[Ludwigia]

1 hour ago, WhodamanHD said:

My reasoning is that if you look closely (magnified below) the blade has two cusps on it whereas uppers usually only have one. I don’t think the photo you provided has them arranged as lowers on bottom and uppers on top. But I could be wrong, The only Cows I’ve found are lowers.

 

Thanks. I think I see your point. It's actually difficult to determine.

[Ludwigia]

1 hour ago, Max-fossils said:

Nice teeth Roger! 

@WhodamanHD @Ludwigia I don't think it's possible to tell whether the tooth is upper or lower, it's too incomplete. And this image (from fossilguy.com ) shows that it could be either. Shame it's broken, would've been a nice one otherwise!

 

For the other teeth, this is what I would say:

• #1 could be C. cuspidata, but it might also be another (like C. acutissima). But most likely in the Carcharias genus. 
• Then for #3, the left one is too hard to tell because it's incomplete (and we can't tell if it had cusps or not). The right one, I'm not sure from the photo's whether the tooth is meant not to have cusps, or if they just got worn off. If it doesn't have cusps (and wasn't meant to) then it wouldn't be a Carcharias. Maybe something like Isurus oxyrinchus? Not sure...
• I don't think #4 is Odontaspis reticulata, as that species frequently seems to have cusps, which your teeth lack. It's some other kind of (sand tiger?) shark, but which one I can't tell
• I think #5 could be Carcharodon hastalis (not the front teeth, but more towards the posterior)? Again very worn which makes it difficult to tell...
• The ones in #6 are out of my league for my limited knowledge...

It's a shame that the teeth are so worn, because that's what is making ID so much more difficult...

But (although the colors aren't very visible on your teeth, I'm saying this due to the variability in shades of grey ) the preservation and colors look very similar to the Eocene teeth of Balegem in Belgium. Perhaps the sediment type is very similar, making the fossilization processes also similar (and hereby giving similarly-looking shark teeth)?

 

Nice to see that you were out hunting for shark teeth, must have been a big change from the ammonites, no?  

 

Best regards,

 

Max

Thanks for your input, Max. I guess you're right about the cow shark. I'll stick to Carcharias sp. for #3 then. I see what you mean with #4. I guess I'll just have to go with Carcharias sp. for them as well. Problem is, I can't find any in the internet that have no cusps and those stripes that can be seen. I'm not so sure about your assessment of hastalis for #5 and am leaning more towards Isurus now.

It certainly is much more relaxing to scratch these out than it is hammering, chiseling and prying ammonites out of a row of blocks on a steep hill.

 

Edit: I just stumbled across Striatolamia macrota for #4. Although they do have very small cusps, they could be just worn off.

 

[Ludwigia]

Hooray! I've just discovered a great website on the shark fauna of southern Germany which has helped me solve my problems with the striped ones. They appear to be the anterior teeth of Mitsukurina lineata                                      

[Miocene_Mason]

15 minutes ago, Ludwigia said:

Hooray! I've just discovered a great website on the shark fauna of southern Germany which has helped me solve my problems with the striped ones. They appear to be the anterior teeth of Mitsukurina lineata                                      

That’s rare for the miocene (at least over here). Nice goblins

BTW I do think 5 are in the genus Isurus, probably Isurus desori uppers.

[Ludwigia]

15 minutes ago, WhodamanHD said:

That’s rare for the miocene (at least over here). Nice goblins

BTW I do think 5 are in the genus Isurus, probably Isurus desori uppers.

My first goblins. Well, actually I have found these before, but just didn't realize what they are until now. Ok. I think I'll just stick to Isurus sp. I also now think that the two in #3 are Carcharias crassidens, thanks to a paper which I'd forgotten I had. Thanks for all your help.

[The Jersey Devil]

#2 is definitely a cow shark (likely Notorynchus) lower because the one cusp that is not broken off has relatively strong distal curvature.

[Miocene_Mason]

41 minutes ago, Ludwigia said:

My first goblins. Well, actually I have found these before, but just didn't realize what they are until now. Ok. I think I'll just stick to Isurus sp. I also now think that the two in #3 are Carcharias crassidens, thanks to a paper which I'd forgotten I had. Thanks for all your help.

Glad you got the IDs you needed!

[Ludwigia]

8 hours ago, josephstrizhak said:

#2 is definitely a cow shark (likely Notorynchus) lower because the one cusp that is not broken off has relatively strong distal curvature.

Thank you

 

8 hours ago, WhodamanHD said:

Glad you got the IDs you needed!

Once again, thanks for your help

[Max-fossils]

On 5/5/2018 at 1:21 AM, Ludwigia said:

Hooray! I've just discovered a great website on the shark fauna of southern Germany which has helped me solve my problems with the striped ones. They appear to be the anterior teeth of Mitsukurina lineata                                      

That’s awesome, and I’ve never heard of the species before, so well done!

 

On 5/4/2018 at 11:18 PM, Ludwigia said:

Thanks for your input, Max. I guess you're right about the cow shark. I'll stick to Carcharias sp. for #3 then. I see what you mean with #4. I guess I'll just have to go with Carcharias sp. for them as well. Problem is, I can't find any in the internet that have no cusps and those stripes that can be seen. I'm not so sure about your assessment of hastalis for #5 and am leaning more towards Isurus now.

It certainly is much more relaxing to scratch these out than it is hammering, chiseling and prying ammonites out of a row of blocks on a steep hill.

 

Edit: I just stumbled across Striatolamia macrota for #4. Although they do have very small cusps, they could be just worn off.

 

As I said I am no expert on shark teeth, so I am likely wrong on some of them. But that’s the best I could come up with, and I’m glad that it did help a bit  

I also kinda agree with the conclusions you came up with, #5 could very well be Isurus, and #3 are possibly Carcharias. And #4 are defibitely Mitsukurina, good spot.

 

[Max-fossils]

On 5/4/2018 at 9:50 PM, WhodamanHD said:

My reasoning is that if you look closely (magnified below) the blade has two cusps on it whereas uppers usually only have one. I don’t think the photo you provided has them arranged as lowers on bottom and uppers on top. But I could be wrong, The only Cows I’ve found are lowers.

Oh yeah, well seen Mason!!! I scrolled past too fast to be able to see that tiny little cusp. You’re probably right then saying that the tooth is lower. Good eye! 

[Miocene_Mason]

4 hours ago, Max-fossils said:

Oh yeah, well seen Mason!!! I scrolled past too fast to be able to see that tiny little cusp. You’re probably right then saying that the tooth is lower. Good eye! 

Thanks, now I just gotta make them good enough to find things!

[Max-fossils]

9 hours ago, WhodamanHD said:

Thanks, now I just gotta make them good enough to find things!