Mike Owens Posted September 4, 2008 Share Posted September 4, 2008 (edited) This Echinoid came from Johnson, County, Texas. I found it in a road-cut on Hwy 67 near the Nolan River. I have found several there over the years, but none covered with as many "worm tubes." Could it be Macraster elegans? Thanks Thanks to Lance Hall's map I can give an exact location. Hwy 67 & FM 1434. Great maps Lance! Dimentions: 1 7/8" High X 3 3/4" Wide X 3 3/4" Long. Tried to upload better photos, but only one took. Edited September 4, 2008 by Mike Owens -----"Your Texas Connection!"------ Fossils: Windows to the past Link to comment Share on other sites More sharing options...
Oh-Man Posted September 4, 2008 Share Posted September 4, 2008 Wow - looks like size does matter! That is a big chunk of echinoid! And I drove right by there two weeks ago and never knew to stop. What is geology? "Rocks for Jocks!" Link to comment Share on other sites More sharing options...
Mike Owens Posted September 4, 2008 Author Share Posted September 4, 2008 Wow - looks like size does matter!That is a big chunk of echinoid! And I drove right by there two weeks ago and never knew to stop. It's 3 3/4" X 3 3/4". -----"Your Texas Connection!"------ Fossils: Windows to the past Link to comment Share on other sites More sharing options...
LanceH Posted September 4, 2008 Share Posted September 4, 2008 According to my geo map that area is Weno limestone (Kwl). Link to comment Share on other sites More sharing options...
Uncle Siphuncle Posted September 4, 2008 Share Posted September 4, 2008 Off the top of my head the Kwl gives up M. obesus, M. subobesus, and M. wenoensis, possibly others as well, but I wouldn't know the difference between them if they were side by side. Grüße, Daniel A. Wöhr aus Südtexas "To the motivated go the spoils." Link to comment Share on other sites More sharing options...
tracer Posted September 4, 2008 Share Posted September 4, 2008 Based on what others have said and descriptions in the Akers book on Texas Cretaceous Echinoids, it seems likely that it would be Obesus, because of its size, if it indeed came from the Weno. Having said that, I'm going solely on size and location, since your flash washed out the details of the echinoid. Link to comment Share on other sites More sharing options...
Mike Murphy Posted September 4, 2008 Share Posted September 4, 2008 Mike: The size of the echinoid and the stratigraphy (Weno) indicates that it could be Macraster obesus, Macraster subobesus or Macraster wenoensis. It is hard to tell clearly from the photographs. All three are large species of Macraster and they are very similar. The height of the test can help to determine which species this represents. The height is not apparent in these photographs. Macraster obesus is quite tall as well as long and wide. Macraster subobesus is also wide and long, but is not nearly as tall as Macraster obesus. Macraster wenoensis is not as long as either Macraster obesus or Macraster subobesus. The height of Macraster wenoensis is similar to that of Macraster subobesus. I use the ratio of height to width and height to length to distinguish between these similar species. I use h/l=0.64 and w/l=0.98 for Macraster obesus; h/l=0.58 and w/l=0.90 for Macraster subobesus; and h/l=0.58 and w/l=0.95 for Macraster wenoensis. These dimension values are based on the average of the holotype measurements and at least 2 other specimens of each species. I hope that this helps. I agree that Lance's maps are a big help in determining the stratigraphy of an area and use them extensively due to the updated street and highway information. Mike Link to comment Share on other sites More sharing options...
tracer Posted September 4, 2008 Share Posted September 4, 2008 The moral of this story is to take your slide rule in the field. And if you're a subobesus, and notice your kid's taller than you, go home and have a little talk with momma. (For any young people in the audience, a "slide rule" is a baseball term which has no relevance in this context and was thrown in just for "randomness".) Link to comment Share on other sites More sharing options...
MOROPUS Posted September 4, 2008 Share Posted September 4, 2008 The moral of this story is to take your slide rule in the field. And if you're a subobesus, and notice your kid's taller than you, go home and have a little talk with momma.(For any young people in the audience, a "slide rule" is a baseball term which has no relevance in this context and was thrown in just for "randomness".) HAHAHAHA!!!! Link to comment Share on other sites More sharing options...
Mike Owens Posted September 4, 2008 Author Share Posted September 4, 2008 See if these photos are clearer. I cut down the brightness. -----"Your Texas Connection!"------ Fossils: Windows to the past Link to comment Share on other sites More sharing options...
tracer Posted September 5, 2008 Share Posted September 5, 2008 Oh, heck man, you found an URCHIN! I can't help with that. I don't know anything about urchins. I thought you'd said you found an "egg" and were "annoyed" that you didn't know what kind it was. I'm outta here... (P.S. - learn this technique. It's how I make face-saving exits whenever I've realized in the middle of a conversation that everyone around me knows much more about the subject under discussion than I do. Leaves them wondering.) (P.P.S. - I once decided to read up on the modern, existing version of burrowing urchins and man, it was interesting.) Link to comment Share on other sites More sharing options...
Mike Owens Posted September 5, 2008 Author Share Posted September 5, 2008 Oh, heck man, you found an URCHIN! I can't help with that. I don't know anything about urchins. I thought you'd said you found an "egg" and were "annoyed" that you didn't know what kind it was. I'm outta here...(P.S. - learn this technique. It's how I make face-saving exits whenever I've realized in the middle of a conversation that everyone around me knows much more about the subject under discussion than I do. Leaves them wondering.) (P.P.S. - I once decided to read up on the modern, existing version of burrowing urchins and man, it was interesting.) Whatever your on -- I want some! Are the photos clearer for you? -----"Your Texas Connection!"------ Fossils: Windows to the past Link to comment Share on other sites More sharing options...
tracer Posted September 5, 2008 Share Posted September 5, 2008 <singing (of course> "I can see clearly now, the grain is gone." Now if you could just get a donkey to haul off some of the marl on that specimen (try using a marlburro). I still think it's an obesus, but since I don't know anything about anything, your mileage may vary. If you google "macraster obesus", you only get like 8 hits, so what I'd really suggest is that you go put that thing back where you found it and get something more common to take pictures of and discuss online. Aren't there any "snails" or "clams" in your area? Here's another thought - go get some great specimens with intact tests of a species that looks nothing at all like a macraster. then break off pieces of the tests and glue them all over a macraster to create sort of a "wolf-in-sheep's-clothing fossil". Then just leave it on an exposure of any formation you know neither echinoid exists in, anywhere near the DFW area, where people apparently take numbers and stand in line at each exposure. Then wait until a psuedoscientist gets the thing named after himself, and then start posting slam pieces about the fraud and suggesting he move to Morocco. Would that be wrong? OK, well, then, nevermind. I wouldn't have made a good scientist, I guess... <wandering away to contemplate in solitude I went wrong> P.S. - Years ago, I swam underwater on this big old scary river and yanked on a guy's leg who was also in the river. Probably scared him. I always wondered how that guy turned out and if he was permanently affected by the experience. Guess I'll never know... Link to comment Share on other sites More sharing options...
Mike Murphy Posted September 7, 2008 Share Posted September 7, 2008 Mike: Based on the apparent dimensions of the echinoid test, I agree that the echinoid is Macraster obesus Adkins, 1930. Mike Link to comment Share on other sites More sharing options...
Mike Owens Posted September 7, 2008 Author Share Posted September 7, 2008 Thanks to all y'all for your input. Mike -----"Your Texas Connection!"------ Fossils: Windows to the past Link to comment Share on other sites More sharing options...
lawooten Posted September 13, 2008 Share Posted September 13, 2008 We went collecting yesterday and found three complete crabs in matrix, one Linthia hanoverensis, one Maretia subrostrata and one Hardouinia kellumi. Pic is of H. kellumi The best days are spent collecting fossils Link to comment Share on other sites More sharing options...
lawooten Posted September 13, 2008 Share Posted September 13, 2008 This is another view of H. kellumi The best days are spent collecting fossils Link to comment Share on other sites More sharing options...
Synechodus Posted September 14, 2008 Share Posted September 14, 2008 We went collecting yesterday and found three complete crabs in matrix, one Linthia hanoverensis, one Maretia subrostrata and one Hardouinia kellumi. Pic is of H. kellumi As an echinoid-afficionado: that's what my dreams are made of ..... Got any pics of the other stuff, especially the Linthia and Maretia? I would love to see those... Cheers, Paul "And the men who hold high places, Must be the ones to start To mould a new reality, Closer to the Heart" (Rush, "Closer to the Heart" from the album "A Farewell to Kings") Link to comment Share on other sites More sharing options...
lawooten Posted September 14, 2008 Share Posted September 14, 2008 This is another view of H. kellumi Will take more pics and post The best days are spent collecting fossils Link to comment Share on other sites More sharing options...
Synechodus Posted September 14, 2008 Share Posted September 14, 2008 Will take more pics and post Look forward to it.... "And the men who hold high places, Must be the ones to start To mould a new reality, Closer to the Heart" (Rush, "Closer to the Heart" from the album "A Farewell to Kings") Link to comment Share on other sites More sharing options...
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