Rayminazzi Posted October 14, 2018 Share Posted October 14, 2018 Found this in pecan gap chalk, nautaloid? Link to comment Share on other sites More sharing options...
Heteromorph Posted October 14, 2018 Share Posted October 14, 2018 Nice find! It is not a nautiloid but a gastropod, possibly Gyrodes sp. or something similar to it. A nautiloid steinkern (cast) such as your's would have straight sutures. Link to comment Share on other sites More sharing options...
PFOOLEY Posted October 14, 2018 Share Posted October 14, 2018 Pecan Gap Nautiloid examples @Uncle Siphuncle "I am glad I shall never be young without wild country to be young in. Of what avail are forty freedoms without a blank spot on the map?" ~Aldo Leopold (1887-1948) New Mexico Museum of Natural History Bulletins Link to comment Share on other sites More sharing options...
KimTexan Posted October 14, 2018 Share Posted October 14, 2018 I can tell you it is not a Pachydiscus. May we see the aperture? It is the mouth or opening of the shell. If it is a cephalopod and the whorl shape is preserved that will help us have a better idea of what it is. May we also have something for scale? To my knowledge there are no nautili reported in the Pecan Gap, but that doesn’t mean they aren’t there. The Ozan has had these reported in it: This is the Eutrephoceras dekayi from the Ozan. There is a line on the outside edge almost in the center. Does that look like a siphuncle? If so it cannot be a nautilus. Their siphuncle is internalized. There is a gastropod I have found which is somewhat similar, but the center isn’t recessed like that. Kim Link to comment Share on other sites More sharing options...
Rayminazzi Posted October 14, 2018 Author Share Posted October 14, 2018 There is really no aperture to speak of. Link to comment Share on other sites More sharing options...
Rayminazzi Posted October 14, 2018 Author Share Posted October 14, 2018 Forgot to add scale Link to comment Share on other sites More sharing options...
Heteromorph Posted October 14, 2018 Share Posted October 14, 2018 1 hour ago, PFOOLEY said: Pecan Gap Nautiloid examples @Uncle Siphuncle Interesting. So apparently Pecan Gap nautiluses don’t necessarily show sutures, similar to Austin Chalk nautilus preservation. Not so sure now, but if I am looking at the pictures right it still looks more like a gastropod to me. Could we get a few close-ups of the center? Link to comment Share on other sites More sharing options...
Rayminazzi Posted October 14, 2018 Author Share Posted October 14, 2018 Link to comment Share on other sites More sharing options...
Ludwigia Posted October 14, 2018 Share Posted October 14, 2018 I'd tend to call it a gastropod. Pity that it's so 2-dimensional which makes determination difficult. Greetings from the Lake of Constance. Roger http://www.steinkern.de/ Link to comment Share on other sites More sharing options...
JarrodB Posted October 14, 2018 Share Posted October 14, 2018 Nice find. That's my hunting grounds also. Link to comment Share on other sites More sharing options...
Uncle Siphuncle Posted October 14, 2018 Share Posted October 14, 2018 Kpg nautiloids tend to be rather nondescript and compressed, often on funky angles. From what I can make out on my phone, this one is better than most. Grüße, Daniel A. Wöhr aus Südtexas "To the motivated go the spoils." Link to comment Share on other sites More sharing options...
KimTexan Posted October 14, 2018 Share Posted October 14, 2018 1 hour ago, Uncle Siphuncle said: Kpg nautiloids tend to be rather nondescript and compressed, often on funky angles. From what I can make out on my phone, this one is better than most. So are you leaning towards nautilus rather than gastropod? I’m up in the air. How wide the whorl is makes me think gastropod, but the center makes me think cephalopod. I have seen gastropods with the top, center knocked out, but the whorls around the center in those cases are very thin and fine. I think the detail necessary for determining the class of mollusk it is is missing. Link to comment Share on other sites More sharing options...
Rayminazzi Posted October 14, 2018 Author Share Posted October 14, 2018 Different place but same formation, found this today. Link to comment Share on other sites More sharing options...
Uncle Siphuncle Posted October 14, 2018 Share Posted October 14, 2018 2 hours ago, Rayminazzi said: Different place but same formation, found this today. Nice Pachydiscus travisi. Most always compressed in the local Kpg. Grüße, Daniel A. Wöhr aus Südtexas "To the motivated go the spoils." Link to comment Share on other sites More sharing options...
Uncle Siphuncle Posted October 14, 2018 Share Posted October 14, 2018 4 hours ago, KimTexan said: So are you leaning towards nautilus rather than gastropod? I’m up in the air. How wide the whorl is makes me think gastropod, but the center makes me think cephalopod. I have seen gastropods with the top, center knocked out, but the whorls around the center in those cases are very thin and fine. I think the detail necessary for determining the class of mollusk it is is missing. Having not seen it in person, I’d hedge toward nautiloid at this point. The Kpg seems to preserve them in the most nondescript fashion of all Texas formations I’ve hunted. Grüße, Daniel A. Wöhr aus Südtexas "To the motivated go the spoils." Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.