Meg Symphyseal tooth?

[Sacha]

Went to the Peace River yesterday to beat the cold front and rain for a very pleasant 85 degree day of digging with friends. My streak of poor performance continues but I found one item I thought might be of interest. First, the take for the day:

 

 

Now in December of 2016 I found a small meg tooth that @MarcoSr identified as a meg symphyseal tooth, which Tony @ynot picked up at auction. This little tooth looks quite similar to me, but has a somewhat shorter blade. Is it another symphyseal tooth, or just an ordinary posterior? I may need to get a better picture of it.

 

[ynot]

Nice tooth, but it looks posterior to Me.

[Plax]

amazing how much the third one from the left in the top row looks like a squalicorax. An impossibility of course but a good example of provenance disproving a possibility. 

[Sacha]

Here's a better picture.

 

[Searcher78]

I always assume the little ones are the back teeth, but I could be wrong.

[MarcoSr]

3 hours ago, Sacha said:

Now in December of 2016 I found a small meg tooth that @MarcoSr identified as a meg symphyseal tooth, which Tony @ynot picked up at auction. This little tooth looks quite similar to me, but has a somewhat shorter blade. Is it another symphyseal tooth, or just an ordinary posterior? I may need to get a better picture of it.

 

 

2 hours ago, Sacha said:

Here's a better picture.

 

 

 

Nice tooth but definitely a posterior tooth.

 

EDIT: Here is a picture of a meg symphyseal tooth (.63"):

 

 

 

 

 

Marco Sr.

[Searcher78]

1 hour ago, MarcoSr said:

 

Nice tooth but definitely a posterior tooth.

 

EDIT: Here is a picture of a meg symphyseal tooth (.63"):

 

 

 

 

 

Marco Sr.

Nice! The enamel goes down the side of the root.

[Sacha]

I see the difference. Here is a picture of the one I was referencing, that Tony has now, and the enamel does extend further on one side than the other.

 

[Shellseeker]

John,

Glad you go out...it was a gorgeous day..  I am thinking that we found about the same items on my last trip... I got a horse ear bone and a dolphin tooth, plus 1 decent Meg , the rest broke up.

Years back , we went hunting in March mania, and I found this one of my favorites. In all my years I have never found a Meg symphyseal... Finding a tiny posterior is tough enough. Would love to pick up 2-3 more....

[siteseer]

9 hours ago, Sacha said:

I see the difference. Here is a picture of the one I was referencing, that Tony has now, and the enamel does extend further on one side than the other.

 

 

It's more the shape of the root that indicates a symphyseal though it isn't always the same shape.  In a posterior the root lobes are spread out and the crown is low.  In a symphyseal the crown can be a little higher and the root can be a little higher.   The lobes are somewhat pointed and constricted laterally (mesiodistally).  Symphyseals are always irregular.  They're rare because very few individuals would have that file by the Late Miocene.  Dentitions in a lineage become more efficient over time, doing the same work (or more work) with fewer teeth.  That frees up energy for elsewhere in the body. 

 

The symphyseal file doesn't appear to be common even in its rather distant ancestor, Otodus obliquus.  An ancestor of Otodus must have had at least one symphyseal file as part of its normal dentition.

 

Jess

 

 

[MarcoSr]

9 hours ago, siteseer said:

 

The symphyseal file doesn't appear to be common even in its rather distant ancestor, Otodus obliquus.  An ancestor of Otodus must have had at least one symphyseal file as part of its normal dentition.

 

Jess

 

 

 

Jess

 

Below are pictures of two Otodus symphyseals from the Eocene of Virginia collected by a good friend of mine.  Daryl took the pictures.  They were found in situ relatively close to each other.  We believe that they are associated because of their close proximity in the formation and the fact that Otodus teeth are not common at all from the formation.  I've found five total and my friend around eight total including these two in over twenty years of collecting.  From the slant of the crowns it looks like this shark had at least two symphyseal files.

 

 

    

 

 

Marco Sr.

[siteseer]

On 2/27/2020 at 6:01 AM, MarcoSr said:

 

Jess

 

Below are pictures of two Otodus symphyseals from the Eocene of Virginia collected by a good friend of mine.  Daryl took the pictures.  They were found in situ relatively close to each other.  We believe that they are associated because of their close proximity in the formation and the fact that Otodus teeth are not common at all from the formation.  I've found five total and my friend around eight total including these two in over twenty years of collecting.  From the slant of the crowns it looks like this shark had at least two symphyseal files.

 

 

    

 

 

Marco Sr.

 

Marco Sr.,

 

Wow, great finds.  After all my Tucson trips and talking to collectors, I don't see too many from the Ypresian of Morocco either.  I think I have just two of those.

 

Jess

 

[MarcoSr]

12 hours ago, siteseer said:

 

Marco Sr.,

 

Wow, great finds.  After all my Tucson trips and talking to collectors, I don't see too many from the Ypresian of Morocco either.  I think I have just two of those.

 

Jess

 

 

Jess

 

I rarely purchase fossils but I have bought two Otodus Obliquus symphyseals and one Otodus sokolovi symphyseal from Morocco from a good friend who is a fossil dealer. I was really surprised by a facebook post by Dr. David Ward a few years back where he showed a picture of over a 100 Otodus obliquus symphyseals that he had.  If you go to Morocco itself, you can probably get a good number of the rarer shark teeth that don't make it out in the general market.  I have a friend from Belgium who bought a number of really rare Moroccan teeth directly from mine workers and local Moroccan dealers when he was in Morocco on fossil hunting trips years ago.  Trying to buy directly from the mine workers today when they get off the buses leaving the mines would probably get you in big trouble with the big dealers who now control most of that trade.

 

Marco Sr. 

[siteseer]

3 hours ago, MarcoSr said:

 

Jess

 

I rarely purchase fossils but I have bought two Otodus Obliquus symphyseals and one Otodus sokolovi symphyseal from Morocco from a good friend who is a fossil dealer. I was really surprised by a facebook post by Dr. David Ward a few years back where he showed a picture of over a 100 Otodus obliquus symphyseals that he had.  If you go to Morocco itself, you can probably get a good number of the rarer shark teeth that don't make it out in the general market.  I have a friend from Belgium who bought a number of really rare Moroccan teeth directly from mine workers and local Moroccan dealers when he was in Morocco on fossil hunting trips years ago.  Trying to buy directly from the mine workers today when they get off the buses leaving the mines would probably get you in big trouble with the big dealers who now control most of that trade.

 

Marco Sr. 

 

Marco Sr.,

 

A few years ago, I was talking to David at Tucson about pathological teeth from Morocco..  He said pretty much the same thing about those, having numerous examples of those too.  I don't know if he still goes there but I assume he's done some collecting in all the phosphate layers and probably other deposits in the region as well.

 

Jess