jeepinthemud Posted July 12, 2009 Share Posted July 12, 2009 Hmm... This is by far my best (at least most unique/favorite) find... It was from the Lower Cret..... in the Limestone surrounding Lake Travis, Austin, TX.... Its about an 1 3/4 inches long... There is a little small square piece of what looks to be the same material just above it in the first and third picture... I also know there is more stuff hidden in this rock (as seen in picture 4), but I dont want to fracture it for fear of harming my little fossil! "To do is to be." -Socrates "People are Stupid." -Wizard's First Rule "Happiness is a warm Jeep." -Auspex Link to comment Share on other sites More sharing options...
LanceH Posted July 12, 2009 Share Posted July 12, 2009 Looks like an internal mold from a Nerinea gastropod. Link to comment Share on other sites More sharing options...
Auspex Posted July 12, 2009 Share Posted July 12, 2009 That's pretty neat looking! Lance, don't gastropods get bigger as they grow? This seems to be the same thickness from end to end. (Not that I know anything about Nerinea). BTW, in this enlargement from the second pic, is this maybe a fish tooth? "There has been an alarming increase in the number of things I know nothing about." - Ashleigh Ellwood Brilliant “Try to learn something about everything and everything about something.” - Thomas Henry Huxley >Paleontology is an evolving science. >May your wonders never cease! Link to comment Share on other sites More sharing options...
LanceH Posted July 12, 2009 Share Posted July 12, 2009 I was just looking through "Texas Cretaceous Gastropods" and the cross sections of the Nerineas are totally different and would not produce a smooth cork-screw internal mold like in the pics. There are some Turritellas that are elongated though that would produce a smooth cork screw type internal mold.... Hopefully a snail expert will chime in. Link to comment Share on other sites More sharing options...
fowells Posted July 12, 2009 Share Posted July 12, 2009 Looks like an internal mold from a Nerinea gastropod. There is a road cut north of San Antonio with lots of this discreet, not in matrix. Notice it is a double helix. The larger coil has square shoulders, the smaller is round in section. I have some pieces 3/16" dia. and 2" long and the diameter, as in this photo, is constant one end to the other. How can it be a gastropod? Link to comment Share on other sites More sharing options...
jeepinthemud Posted July 12, 2009 Author Share Posted July 12, 2009 Hmm.. is there any part that anyone wants me to try and get a better picture of? and welcome to the forum, fowells! Auspex, im not sure if its a tooth... want me to try and focus a picture on that? "To do is to be." -Socrates "People are Stupid." -Wizard's First Rule "Happiness is a warm Jeep." -Auspex Link to comment Share on other sites More sharing options...
Auspex Posted July 12, 2009 Share Posted July 12, 2009 There is a road cut north of San Antonio with lots of this discreet, not in matrix. Notice it is a double helix. The larger coil has square shoulders, the smaller is round in section. I have some pieces 3/16" dia. and 2" long and the diameter, as in this photo, is constant one end to the other.How can it be a gastropod? Based on your matrix-free specimen description, it can't be. Neither can it be any ichnofossil I've ever heard of. Pat, where are you? "There has been an alarming increase in the number of things I know nothing about." - Ashleigh Ellwood Brilliant “Try to learn something about everything and everything about something.” - Thomas Henry Huxley >Paleontology is an evolving science. >May your wonders never cease! Link to comment Share on other sites More sharing options...
mommabetts Posted July 12, 2009 Share Posted July 12, 2009 That is one i have never seen before, very interesting, will have to watch this one. Link to comment Share on other sites More sharing options...
Guest solius symbiosus Posted July 12, 2009 Share Posted July 12, 2009 Meso. stuff is out of my realm, but could it be the anchoring part of a fenestrate bryozoan(where the fronds attach)? Link to comment Share on other sites More sharing options...
jkfoam Posted July 12, 2009 Share Posted July 12, 2009 I once saw a turritelloid type snail from the Texas Edwards that was in matrix that was about 24 inches long (Only the exposed part. It could not have been more that an inch wide at its widest and the edges seemed almost parallel. I can only speculate as to what the total lenght would have been. I remember thinking, when I viewed it, what a wild looking snail and what it must have looked like in life. The Cretaceous seas must have been something extraordinary to see.. The juvenile must have appeared similiar to what is pictured here. JKFoam The Eocene is my favorite Link to comment Share on other sites More sharing options...
fowells Posted July 12, 2009 Share Posted July 12, 2009 I had forgotten about the big piece, which I didn't realize was the same stuff until I went back and looked through all I found at that site. Pursuing the gastropod possibility, we noted a slight change in diameter in each of the little pieces and arranged them end to end. The result would be a very a long snail indeed. Link to comment Share on other sites More sharing options...
erose Posted July 12, 2009 Share Posted July 12, 2009 Along Lake Travis it is most likely to be from the Glen Rose Formation. It matrix looks like some of the typical dolomite that makes up many beds of that formation. Just a bit harder than the limestones and often forming the benches of that typical "stair step topography." Those of you that know the Hill Country know exactly what I'm talking about. I would put good money on it being a gastropod. There are a number of types that are long and barely expand as they grow. But just being an internal cast it would be very hard to ID. The little square may be a piece of oyster shell or a bit of crinoid/echinoderm. The little straight thingy might be a urchin spine. Link to comment Share on other sites More sharing options...
Auspex Posted July 12, 2009 Share Posted July 12, 2009 The result would be a very a long snail indeed. Can you imagine what the seafloor might have looked like, bristling with these, all in slow motion? "There has been an alarming increase in the number of things I know nothing about." - Ashleigh Ellwood Brilliant “Try to learn something about everything and everything about something.” - Thomas Henry Huxley >Paleontology is an evolving science. >May your wonders never cease! Link to comment Share on other sites More sharing options...
fowells Posted July 12, 2009 Share Posted July 12, 2009 Can you imagine what the seafloor might have looked like, bristling with these, all in slow motion? My big problem with it being a gastropod is the "double helix" characteristic. You can see that there is a square shouldered coil twinned with a smaller round coil. If a bryozoan, it might look something like Archimedes with a "stiffener" attached. Link to comment Share on other sites More sharing options...
Auspex Posted July 12, 2009 Share Posted July 12, 2009 If the living chamber was somewhat "hourglass-shaped" in cross section (perhaps for strength), might it leave an internal cast shaped like this? "There has been an alarming increase in the number of things I know nothing about." - Ashleigh Ellwood Brilliant “Try to learn something about everything and everything about something.” - Thomas Henry Huxley >Paleontology is an evolving science. >May your wonders never cease! Link to comment Share on other sites More sharing options...
Terry Dactyll Posted July 13, 2009 Share Posted July 13, 2009 Jeep..... Nice finds.... very unusual.... Cheers Steve... And Welcome if your a New Member... Link to comment Share on other sites More sharing options...
MikeD Posted July 13, 2009 Share Posted July 13, 2009 I have also seen these in the Glen Rose formation. I saw one that was 12 inches long and easily an inch in diameter and that was only a piece of it. Have not ID'ed it yet. Link to comment Share on other sites More sharing options...
Guest N.AL.hunter Posted July 13, 2009 Share Posted July 13, 2009 Could these be burrows of some sort? I have never seen anything like them before, so very interesting find. Link to comment Share on other sites More sharing options...
fowells Posted July 17, 2009 Share Posted July 17, 2009 If the living chamber was somewhat "hourglass-shaped" in cross section (perhaps for strength), might it leave an internal cast shaped like this? If a gastropod, this thing would be a "conjoined twin", since it is 2 coils wrapping around a central axis. I've got several dozen pieces and there is no trace of a termination at either end of any of them. Very strange. Link to comment Share on other sites More sharing options...
jeepinthemud Posted July 17, 2009 Author Share Posted July 17, 2009 does it have two separate coils? looking at my image, it seems that if it had two separate coils, then each one would have a very steep angle on one side and a much smaller on this side... (im not saying it doesnt, it just seems likely that the angles of the coil would be similar, not radically different...) "To do is to be." -Socrates "People are Stupid." -Wizard's First Rule "Happiness is a warm Jeep." -Auspex Link to comment Share on other sites More sharing options...
Uncle Siphuncle Posted July 17, 2009 Share Posted July 17, 2009 I find both of these Nerinea-like gastropods in the hard limestone capping the Salenia texana marl, which is the contact of the Upper and Lower Glen Rose formations, about 108 MYA. If this exposure has a soft marl 2-8 feet thick immediately below the a layer of harder rock with abundant skinny gastropods as shown, and the underlying marl has tons of tiny disk shaped Ortbitolina texana forams, you should look hard for echinoids S. texana echinoids, Palhemiaster comanchei, Heteraster obliquatus, Coenholectypus planatus, Tetragramma texanum, and possibly a more rare Phyllacanthus texanus. Look for white crab claws Paleopagurus banderensis and occasional crab carapaces and floating crinoids as well. Grüße, Daniel A. Wöhr aus Südtexas "To the motivated go the spoils." Link to comment Share on other sites More sharing options...
fowells Posted July 17, 2009 Share Posted July 17, 2009 OK. Here's some pieces of the mystery fossil and a couple of inside casts of turitella. I've drawn a line on the center of each coil. As you can see on the snail, one whorl, one line. On the whatever it is, two coils, two center lines. And again, one of the coils has square shoulders and the other is round in cross section. The alternating flat/round coils are especially pronounced in the photos of your find. Link to comment Share on other sites More sharing options...
Auspex Posted July 17, 2009 Share Posted July 17, 2009 Texas Tech has this image on their website: Nerinea incisa http://images.google.com/imgres?imgurl=htt...sa%3DN%26um%3D1 "There has been an alarming increase in the number of things I know nothing about." - Ashleigh Ellwood Brilliant “Try to learn something about everything and everything about something.” - Thomas Henry Huxley >Paleontology is an evolving science. >May your wonders never cease! Link to comment Share on other sites More sharing options...
fowells Posted July 18, 2009 Share Posted July 18, 2009 Texas Tech has this image on their website: Nerinea incisa http://images.google.com/imgres?imgurl=htt...sa%3DN%26um%3D1 That's the stuff. Has anyone got a link that shows what the living creature may have looked like? Danwoehr describes the site perfectly (but doesn't mention it is steinkern city). These are some of the echinoids from there. from the site. Quick ID, danwoehr? Link to comment Share on other sites More sharing options...
jeepinthemud Posted July 18, 2009 Author Share Posted July 18, 2009 that seems to have a slightly different coiling pattern than the one I posted... but maybe its just because mine has been worn away some... "To do is to be." -Socrates "People are Stupid." -Wizard's First Rule "Happiness is a warm Jeep." -Auspex Link to comment Share on other sites More sharing options...
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