fifbrindacier 3,290 Report post Posted April 4 Hi, a friend of mine told me he found some Placentyceras in a place where the geologic ages go from the Albian to the Turonian-Santonian, but most of the stratas of that place are Cenomanian. I believe this fossil is not an ammonite, but rather an Oyster or a rudist. I mostly think about Requienia or Toucasia. The geologic file mention the name of Toncasia bayleia. Do you know if Toncasia is a synonym of Toucasia and do you think i'm right thinking this is a rudist ? Lenght : 7 centimeters. Share this post Link to post Share on other sites
Fossildude19 10,367 Report post Posted April 4 Is there a reason to discount the possibility of being an oyster, such as Gryphaea or Exogyra? The ridges look a bit more 3 dimensional than the images I see of the other options. Share this post Link to post Share on other sites
fifbrindacier 3,290 Report post Posted April 4 You're right, i've mentioned this possibility in the tags but not in the post, i've edited it. Share this post Link to post Share on other sites
Fossildude19 10,367 Report post Posted April 4 Oops! I always forget to look there! Share this post Link to post Share on other sites
DPS Ammonite 2,324 Report post Posted April 4 I cannot see in the pictures where they show if this is an oyster or a rudist that is more like a gastropod. If it is an oyster you should be able to see where the two shells meet or you should be able to see the concave interior of a single shell. If it is a rudist, you should be able to see a small opening with a deeply invaginated interior similar to a snail. You might also see a small shell covering the opening. Please show us the other side (back side) of this: @fifbrindacier Are you able to see and send us a clear photo of where two shells meet if this is an oyster or of the small opening if this is a rudist? What does our rudist expert think? @FranzBernhard Share this post Link to post Share on other sites
FranzBernhard 1,334 Report post Posted April 4 Thanks, @DPS Ammonite, but I am not an expert. Googling for Toucasia yields some examples, also this one: http://le-coin-a-fossiles.fr/barremien.html 2 hours ago, fifbrindacier said: Do you know if Toncasia is a synonym of Toucasia Its just a typical misreading, n for u. Tried googling for -- toucasia bayleia --, but without quotation marks. Yields an old work, bayleia seems to be the name of a genus or subgenus - ? Oh yes, its a genus within the family Requieniidae. But, sorry, I don´t know what your specimen is . Franz Bernhard Share this post Link to post Share on other sites
caterpillar 406 Report post Posted April 4 Take a look at Amphidonte Share this post Link to post Share on other sites
fifbrindacier 3,290 Report post Posted April 5 21 hours ago, caterpillar said: Take a look at Amphidonte I did, and i agree this fits well. I should have listen to my first impression it was an Oyster. Thank you Caterpillar. Share this post Link to post Share on other sites
fifbrindacier 3,290 Report post Posted April 5 Thank you @doushantuo Share this post Link to post Share on other sites
Fossildude19 10,367 Report post Posted April 5 12 minutes ago, doushantuo said: What paper is this from, Ben? Share this post Link to post Share on other sites
doushantuo 3,918 Report post Posted April 5 Not entirely sure,but it MIGHT be from Klaus Bandel,around 1993 ,in the Mitteilungen des Geologisches-Palaontologisches Instituts/Univ.Hamburg Share this post Link to post Share on other sites
piranha 5,360 Report post Posted April 5 2 hours ago, doushantuo said: Not entirely sure,but it MIGHT be from Klaus Bandel,around 1993 ,in the Mitteilungen des Geologisches-Palaontologisches Instituts/Univ.Hamburg MIGHT be or it is not? ...why all the intrigue? LINK The paper is actually by: Mohammad Aqrabawi Amman 1993 Oysters (Bivalvia-Pteriomorphia) of the Upper Cretaceous rocks of Jordan. Palaeontology, Stratigraphy and Comparison with the Upper Cretaceous oysters of Northwest Europe. Mitteilungen aus dem Mineralogisch-Geologischen Institut in Hamburg, 75:1-135 Share this post Link to post Share on other sites
will stevenson 202 Report post Posted April 5 Definitely exogyra I have one myself Share this post Link to post Share on other sites
fifbrindacier 3,290 Report post Posted April 5 40 minutes ago, will stevenson said: Definitely exogyra I have one myself 2 hours ago, piranha said: MIGHT be or it is not? ...why all the intrigue? LINK The paper is actually by: Mohammad Aqrabawi Amman 1993 Oysters (Bivalvia-Pteriomorphia) of the Upper Cretaceous rocks of Jordan. Palaeontology, Stratigraphy and Comparison with the Upper Cretaceous oysters of Northwest Europe. Mitteilungen aus dem Mineralogisch-Geologischen Institut in Hamburg, 75:1-135 Thank you all ! Share this post Link to post Share on other sites
