Shark Tooth and Shell Fossil ID

[Neil.]

Hi, I'm new to this forum.

I have found the following two fossils and would like some opinions on their identification.

The tooth I believe to be a C. Megalodon from the research i have carried out, while the shell is unknown.

I would also like to know what the best approach to cleaning the fossils is.

Any opinions on both their identification will be greatly appreciated.

Thanks.

[Daleksec]

The tooth is a Megalodon. The shell looks to be a chesapecten jeffersonius, but for definite answer I need a location or formation.

[Darktooth]

I would call the tooth chubutensis, due to the cusps.

[JanT]

Agree with @Darktooth, the tooth is definitely chubutensis. See this page (especially the Megalodon Evolution infographic) for explanation of differences between megalodon and chubutensis.

 

It's a nice one, congratulation to your finding! :-)

[sixgill pete]

What is the age of the sediments that the tooth and Chesapecten come from? Knowing this could help get a definite ID on both. If the bivalve is indeed C. jeffersonius, then the tooth is O. megalodon because they would have came out of Pliocene sediments. Please correct me if I am wrong about this.

 

I am not convinced that just the occurrence of rudimentary cusplets makes a tooth O. chubutensis. Some megs can display these , especially juveniles. O. chubutensis is from the early Miocene.

[JanT]

To be honest, I thought that those cusplets are the only difference between megalodon and chubutensis, but you are right. Now I found more info on it and it can be really juvenile megalodon. Sorry if my post was misleading.

[Neil.]

The tooth was found in C2 Phosphorite Conglomerate (early Langhian age), while the Chesapecten was found in the Lower Coralline limestone (Aquitanian age).

 

Thanks everyone for the feedback!

 

[Darktooth]

These are valid points that i know as well. There has been other discussions about juvenile megs with cusps vs chubs. I guess one has to take into account the size of the tooth plus position of the tooth in the jaw and come up with a conclusion on wether this is a juvenile tooth or adult. Does anyone know how big juvenile meg teeth got, as opposed to adult teeth? I do not. But the tooth in question is about 3 1/4 inches, while missing some of the root as well as the tape measure curled up at the end. This is about where my limited knowledge plays out. I did try to take into account the aforementioned things before I made a comment. 

[sixgill pete]

So both of these were found in Miocene aged sediments. Both early Miocene, although the sediments from the Chesapecten are older than the sediments from the tooth, interesting. So, yes, to me anyways, because of the age of the sediments and the cusplets, I would call the tooth a chubutensis. 

 

Darktooth, I was not trying to make it seam that you were out of context with your comment. I was just throwing in my two cents worth. As far as the max size of a juvenile meg, thats a question for someone with more pedigree than I.

[Darktooth]

@sixgill pete 

1 hour ago, sixgill pete said:

So both of these were found in Miocene aged sediments. Both early Miocene, although the sediments from the Chesapecten are older than the sediments from the tooth, interesting. So, yes, to me anyways, because of the age of the sediments and the cusplets, I would call the tooth a chubutensis. 

 

Darktooth, I was not trying to make it seam that you were out of context with your comment. I was just throwing in my two cents worth. As far as the max size of a juvenile meg, thats a question for someone with more pedigree than I.

I fully expect and appreciate others input regardless if it contradicts my own beliefs. I take no offense. And as far as my previous response,  I was only trying to explain the things I took into account to base my opinion on the id.   And I am still learning so I appreciate everbodies 2 cents.