My Rarest Ptychodus

[Tony Eaton]

ptychodus latissimmus, my most unique ptychodus

Up until recently I hadn't been on a dedicated fossil hunt for over 6 years. This was the haul on the last trip about 7 years ago. My wife found this pytchodus latissimmus, I think the only shark tooth she ever found. Well, a good find! I have probably over 100 ptychodus, but the first latissimmus.

We were collecting a Kamp Ranch site in Frisco TX, although this was actually from just inches below Kamp Ranch in the Britton Layer of Eagle Ford (uppermost Cenomanian), which at least at this site was a condensed pebble layer / buff clay layer. The Metoicoceras fragment helped tell me that this was Britton. Otherwise I would have assumed simply a clay layer of Kamp Ranch.

Edited October 6, 2009 by Tony Eaton

[MikeD]

Wow! That's huge.

[kknight]

Ok, I am jealous; there is a Kamp ranch site so close to home and I don’t know about it!

[CreekCrawler]

That's one nice Ptychodus Tony.

[Tony Eaton]

Thanks.

I finally got the Farish and Welton Texas Shark Teeth book and read that P. Latissimmus is common in the Atco contact area although I've yet to find one there. According to the book, Latissimmus is not known to be in Kamp Ranch or Britton which makes me wonder if I have ID'd this tooth correctly.

I have recently found two Ptychodus teeth from P.O.C. found by sieving with window screen that are rather unusual, perhaps "rarer" than the above.

[barefootgirl]

Well dont tease us, show us some picks.

Love that tooth by the way!

[siteseer]

Thanks.

I finally got the Farish and Welton Texas Shark Teeth book and read that P. Latissimmus is common in the Atco contact area although I've yet to find one there. According to the book, Latissimmus is not known to be in Kamp Ranch or Britton which makes me wonder if I have ID'd this tooth correctly.

I have recently found two Ptychodus teeth from P.O.C. found by sieving with window screen that are rather unusual, perhaps "rarer" than the above.

Yes, your tooth is about four million years older than the oldest known occurrence of latissimus as of the publication of that book (1993). Your tooth has ridges too prominent to be polygyrus so I think it is latissimus.

[Tony Eaton]

My son spending the night at a friend's house so I had a chance to use his scanner and get a descent image of the ptychodus teeth.

Here is the odd one. The scan doesn't convey the fact the whole thing is only 2mm thick all the way across.

I guess this could be a corner tooth for a common ptychodus species? Or maybe P. Rugosus, both thinner and earlier than expected.

This one is perhaps ptychodus sp as described in Welton and Farrish book. Still a bit odd IMO as although difficult to tell in this scan there is a small cusp next to the larger one. Taking a second look, maybe a symphysial tooth?

Here is ptychodus sp I think. A closer to the book example.

I wonder if this is some form of hybodus? Only 1mm thick the whole way across.

Ah, completely unrelated except for it is from POC. Seems too hard / crystalized to be a recent pearl so I'm think a shiny fossil one ;-)

Edited November 22, 2009 by Tony Eaton