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Heteromorph

On November 27 of this year my mother and I went hunting in a new housing development exposing the Austin Chalk in North Texas. The first and only site that we got to was covered in this rock that has been brought in from somewhere else. It was odd in that it looked like someone had just poured a bunch of it in an empty lot in no particular pattern. It was all next to a man made hole in the ground in the middle of the lot, but I don't see how that could be related. We have seen bags of this matrix in drainage ditches before and had also seen it variously thrown about at different Austin Chalk sites. I had found a few things in it that were intriguing, but for some reason I had largely (and very incorrectly) assumed that there was probably not much that one could find in it, so I never seriously hunted it.

 

But my mother proved me very wrong! When we got to the site and I saw that much of it was covered in this stuff, I was somewhat annoyed since it was covering up some of the Austin Chalk. But we both got out anyways and began hunting. I went off towards the ditch where more of the Austin Chalk was exposed while she was looking around in the foreign matrix. I wasn't having much luck and she was commenting on how she was seeing some layered patterns in the matrix, pictured in F31. I didn't think much of it and kept hunting away from the pile of unknown matrix. Then less than a minute later my mother let out something along the lines of, "Hey! Hey! Hey! What is this?!" When she does that, I know she is not kidding around! So I went over there and saw her pick this up off of the ground.

 

We both immediately knew that it was an echinoid. What made this specimen really special are the facts that this is the largest or at least second largest echinoid that we have ever found, the first echinoid from a formation other than the Austin Chalk, and our first regular echinoid all in one. Its a sad thing that it is so beat up, but then again its not surprising since it was probably hauled in a bag in the back of some guy's pickup for possibly hundreds of miles. Only two tubercles that have not been knocked off are visible, though perhaps there are one or two more buried under the chunk of matrix stuck to the side of the specimen. It is also missing most of its adoral side and most of its apical disc, with bits of the disc still in the depression that is left. Its test is pretty scuffed up in general, but at least most of it is still left and I don't think that it is too beat up to be identifiable. 

 

I took pictures of the site while I was there (pictures in F1-F4) and brought home a lot of matrix to experiment with and to photograph later to aide in identifying the formation from which it came. When I got home I consulted @Bill Thompson's book on Texas echinoids and I have been able to narrow this specimen down to the genus Temnocidaris for sure. 

 

I am hoping that you guys can help me find out what formation the matrix came from, which would greatly help to narrow down the species possibilities. Out of the four species of Temnocidaris listed in Thompson's book as being reported from Texas only two of them have there tests pictured, T. borachoensis and T. hudspethensis, with the other two species only described from their spines. Now I am not an echinoid expert by an stretch of the imagination, but I am personally leaning towards this being T. borachoensis from the Boracho Formation of Upton county or a nearby county in West Texas. My reasoning is twofold: 

 

First, to me its test much more resembles T. borachoensis than T. hudspethensis in two ways. They are that the interabulacrum tubercles are closer together than T. hudspethensis and that its test is a bit more squat than T. hudspethensis, even if it still had its base. Coincidently, just a little over a month ago @KimTexan posted for identification a Temnocidaris specimen from the Edwards Formation of Johnson county that very much resembles mine, though I can't say for sure it is the same species as mine since her specimen is missing much of its aboral side while mine is missing much of its adoral side, making a comparison between them a bit difficult.  

 

Second, from what I have seen the matrix most closely resembles the San Martine member of the Boracho Formation. If I want to learn a bit about Texas paleontology that I didn't know before I will usually look up one of @Uncle Siphuncle's Fossil hunting reports. Here is one which contains pictures of a lot of matrix and a few fossils from the Boracho formation, starting with Figure 91. The most striking resemblance I see is that the matrix has a lot of red/orange matrix streaks running through it like mine does. But because I have never hunted in the Boracho Formation other than possibly this brought in matrix, I don't know for sure. I also noticed what appears to be the same layered fossil shown in F31 in Figures 136-138. After seeing this post, I tend to think that it is oyster related material. 

 

This matrix is a lot more dense than the Austin Chalk that I am used to, making it noticeably heavier. It bubbles when I put vinegar on it indicating that it is limestone, though perhaps not as vigorously as vinegar on the Austin Chalk. I scraped some matrix with a dentist's pick in the places weakened by vinegar and places I didn't treat with vinegar, and while it did scratch the limestone matrix, the untreated matrix was harder than untreated Austin Chalk. I have tried to see if the sandy red/orange matrix bubbles, but my experiments were inconclusive because the limestone is always nearby, skewing the results. I would assume that it does not bubble on its own. After cleaning the echinoid, a few other fossils, and chunks of matrix, the toothbrush fibers had turned orange indicating that the sandstone it is not that hard, at least when wet. Also the limestone matrix is just packed full of calcite crystals, which is very noticeable in direct sunlight!

 

The specimen its self, excluding any matrix, is 53mm in diameter by 36mm in height, though it would be taller if it still had its base. It appears to me that it is only infilled with the sandstone while there is an actual limestone chunk stuck to the side of it, shown specifically in F12. Notice the red patch on the matrix, a characteristic not unique to this chunk but seen on another chunk of matrix shown in F32.  

 

All of the pictures were taken in sunlight, so the color that you see is how it really looks. 

 

Thanks for any help in advance. 

 

F1-F4. On site photos.

IMG_2603.thumb.JPG.d2320f5105b47b30b0298e19502def74.JPG

F2 

IMG_2482.thumb.JPG.1e5aaa99c66b928f1e14a786a2903a14.JPG

F3

IMG_2483.thumb.JPG.30c13b804b34b6f17db7aca4b8093f8e.JPG

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Heteromorph

F4

IMG_2484.thumb.JPG.797175e1994f68366a312d8536fe2d32.JPG

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Heteromorph

F5. Aboral view.

DSCN5463.thumb.jpg.f3c9f6bd4402b801fa4ef25f4948998c.jpg

F6

DSCN5503.thumb.jpg.d1a6cfae09b3bd90803a928132d20567.jpg

F7

DSCN5469.thumb.jpg.a511088c0a2fe0313e33666e5ccb934f.jpg

F8

DSCN5502.thumb.jpg.68f00e2d5348c128caa26cfaaefd9955.jpg

F9

DSCN5501.thumb.jpg.f0b0baf72fb6a6e4c527e5f6b9159df2.jpg

F10

DSCN5521.jpg

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Heteromorph

F11

DSCN5522.thumb.jpg.74550fcc7e3cf59717de110aeb68741b.jpg

F12

DSCN5490.thumb.jpg.ab0d2535055a02f933c85073302b6385.jpg

F13

DSCN5467.thumb.jpg.00e0fd9916f94d8346165f5f1da07dc9.jpg

F14

DSCN5541.thumb.jpg.5cfccc1328fa188b55dc244cb26fa94f.jpg

F15

DSCN5548.thumb.jpg.73c0303c0911f5bb94c7d7f5f27d99ee.jpg

F16

DSCN5547.thumb.jpg.c7714b5953a69f09b3effd1f84f5573f.jpg

F17

DSCN5517.thumb.jpg.25d8e8b3721775632576b19092b1fb70.jpg

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Heteromorph

F18

DSCN5475.thumb.jpg.92d92d944e239f8d0d34d1e10f71a361.jpg

F19

DSCN5474.thumb.jpg.f4e0cd158819940b22e7b0460f1ad10a.jpg

F20

DSCN5480.thumb.jpg.a78dece52f49d572c9d27419d61538d3.jpg

F21

DSCN5481.thumb.jpg.7c6fb1c7ad38343f96854ec67c02f53c.jpg

F22

DSCN5479.thumb.jpg.968f8e07385b43d33250c24a553699fe.jpg

F23

DSCN5529.thumb.jpg.ff0e9ff294078034fbb784a63e51e896.jpg

F24

DSCN5496.thumb.jpg.e1c232bc50a1052095d791f71c54b7c2.jpg

F25

DSCN5549.thumb.jpg.97f9ff36367d7a0a3e15110d97cd8f0f.jpg

F26

DSCN5531.thumb.jpg.5cffc98d3fa1aa12306ebe574dcf9541.jpg

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Heteromorph

F27. Adoral view.

DSCN5514.thumb.jpg.e5469bfe15972e634b082763a6696154.jpg

F28-F30. Oyster and its matrix, possibly of the genus Chondrodonta.

 

F28

DSCN5677.thumb.jpg.3af171b19c12c80b22e65ce890b6a5e0.jpg

F29. The side of the rock showing calcite crystals which are all through out this matrix. 

DSCN5682.thumb.jpg.ee493cdb3ac4319a4ca360589aec14b2.jpg

F30. Underside of Oyster showing matrix.

DSCN5683.thumb.jpg.3db3e610bd0eaa360c7735a499eac951.jpg

F31-F32. Intricate layered structure probably belonging to an oyster. 

 

F31

DSCN5644.thumb.jpg.07391c73a8f11379c675f6a4404bbf8a.jpg

 

 

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Heteromorph

F32. Underside of layered structure showing matrix. Note the red splotches.

DSCN5658.thumb.jpg.5f696e17e0bf6d11e61bfa13f53dfe38.jpg

F33-F35. Probable rudist from different angles. 

 

F33

DSCN5603.thumb.jpg.3112d68ab844358889d79d393865ccce.jpg

F34

DSCN5701.thumb.jpg.eb2360116a3eb1c4c107c30fa7697f94.jpg

F35

DSCN5611.thumb.jpg.2e0d6ee4ad18605f9b3c213e50f515a5.jpg

 

That's it. 

 

 

 

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Tidgy's Dad

Super photos of some nice finds but can't help i'm afraid. :)

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Heteromorph
4 hours ago, Tidgy's Dad said:

Super photos of some nice finds but can't help i'm afraid. :)

Thanks. :)

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KimTexan

That matrix and the fauna in it looks very similar to where I found mine only yours has a little more iron in it. F31 is almost an exact representation of where I found mine. It is a highly crystalline material throughout. There were also what looked to be burrows in the rock face of the road cut it was in. Some parts do have orange iron stuff in it, but it wasn’t as dominate. I think years ago it was more orange when the road cut was first made, but the iron has weathered out. I own property maybe a mile from where I found my Cidarid.

 

I believe the material came from the Edwards Formation, but I am still a novice at formation ID.

 

If you zoom in on this pic you can see a lot of crystalline material on top right of pic and whatever the striated looking stuff is in the burrowtunnel looking area of the pic.027E09D2-545C-42CA-8935-6CF4F6F8BC99.thumb.jpeg.994af53083d3636e165b74f1a86f7233.jpeg

In this one is more crystalline material and what I believe is a large rusist in the crescent shape in center. Not sure about crescent shape on bottom left. Maybe just more crystal.

C9A61C73-6725-4F5A-BDDD-B21AA369CA95.thumb.jpeg.ebb351f395696b7d5187e5dc49495701.jpeg

 

That is a nice one. It is more complete than mine even if roughed up. I think it is a match to mine.

 

I believe @JohnJ and @erose would be interested in your find.

 

Just out of curiosity did you and you mother have a table at Fossilmania this year? I think I remember talking with you while there.

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Heteromorph
1 hour ago, KimTexan said:

That matrix and the fauna in it looks very similar to where I found mine only yours has a little more iron in it. F31 is almost an exact representation of where I found mine. It is a highly crystalline material throughout. There were also what looked to be burrows in the rock face of the road cut it was in. Some parts do have orange iron stuff in it, but it wasn’t as dominate. I think years ago it was more orange when the road cut was first made, but the iron has weathered out. I own property maybe a mile from where I found my Cidarid.

 

I believe the material came from the Edwards Formation, but I am still a novice at formation ID.

 

If you zoom in on this pic you can see a lot of crystalline material on top right of pic and whatever the striated looking stuff is in the burrowtunnel looking area of the pic.027E09D2-545C-42CA-8935-6CF4F6F8BC99.thumb.jpeg.994af53083d3636e165b74f1a86f7233.jpeg

In this one is more crystalline material and what I believe is a large rusist in the crescent shape in center. Not sure about crescent shape on bottom left. Maybe just more crystal.

C9A61C73-6725-4F5A-BDDD-B21AA369CA95.thumb.jpeg.ebb351f395696b7d5187e5dc49495701.jpeg

 

That is a nice one. It is more complete than mine even if roughed up. I think it is a match to mine.

 

I believe @JohnJ and @erose would be interested in your find.

 

Just out of curiosity did you and you mother have a table at Fossilmania this year? I think I remember talking with you while there.

Thank you for more pictures and information! It does seem to be a match with the Edwards Formation much more than the Boracho Formation and it also just makes much more sense that they would haul in fill rock from just the next county over as apposed to over half way across Texas. That striated tunnel looks just like mine. A picture of an oyster that you posted in your thread appears to me to be the same kind as mine pictured in F28. The limestone itself appears to have the same texture and color. In fact, when I first saw the pictures in your thread I though that the matrix and the fauna looked very similar to mine and had some red/orange matrix in it, but I discounted the possibility that mine was the same because of the apparent lack of it in your matrix as opposed to mine. The fact the it has been weathered away makes much more sense. 

 

I agree, I think that mine is a match to yours. While mine is infilled with the sandy matrix, from the pictures of the echinoid in your thread it appears that yours is infilled with limestone. Is that correct? I find it interesting that there would be different matrix infilling mine. 

 

Do you think that the fossil pictured in F33 is a rudist? That is the only thing that it resembles from what I have seen. Also to answer your question, we didn't have a table at Fossilmania this year but we were there to look around and buy some fossils on its first day. You could have seen us on that Friday if you were there. 

 

Hopefully JohnJ and erose could help confirm the formation and identify the species. 

 

Here are a few more matrix pictures with crystalline material and fauna: 

 

F36-F39. Different angles of the same rock shown in F31.

 

F36

DSCN5564.thumb.jpg.2a76e55cee427d7bcbdae42f6b4991da.jpg

 

F37

DSCN5565.thumb.jpg.dcc27a91ab5fb8a4a82d701890a22414.jpg

 

F38

DSCN5657.thumb.jpg.853a6dfc34e87930172d98b56efc7add.jpg

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Heteromorph

F39

DSCN5562.thumb.jpg.8c2366e433412e2728297c0ee70ad7fd.jpg

F40-F43. Chunk of matrix with striated oyster material and other fauna.

 

F40

DSCN5618.thumb.jpg.f665444ea6243e7d9f1473693602d57c.jpg

 

F41

DSCN5622.thumb.jpg.f4ecee603bb247e012be985a8bbbddb7.jpg

 

F42

DSCN5623.thumb.jpg.19cdda2396f00491e5e376d9f7c8f8c0.jpg

 

F43

DSCN5734.thumb.jpg.65658aea8c04d7b76cf71202bc08ff61.jpg

F44-F46. Oyster shell. 

 

F44

DSCN5595.thumb.jpg.a87eaaf78d91cf060d8e77e559fed56f.jpg

 

F45

DSCN5597.thumb.jpg.c0fbe9b6e99db2d9b30ee6330570fa9e.jpg

 

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Heteromorph

F46

DSCN5596.thumb.jpg.9125d1cd4bb1868e5d9982ac0c20dced.jpg

 

F47. Underside of rock with rudist from F33.

DSCN5698.thumb.jpg.f881414fef3a5e36cf0dc58b095eeef7.jpg

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KimTexan

I do think it could be a rudist. @BobWillcould probably help with that. 

Here is another pic that I posted in my Cidarid post with a rudist in it. There are 2 more of the crescent shaped structures with a wavy edge in this pick. One is in the center and the other is just above and to the right of it. I’m not sure what the tube structure is. It is 5-6 inches long.F5893267-B48B-4DCF-98C1-0C0826CC3E15.thumb.jpeg.8f6243668f0785b1282675cb30c2eeab.jpeg

 

I was not there at Fossilmania on Friday. I was only there Saturday afternoon late and at the auction.

Do you and your mother attend the DPS meetings? If so I’ll be there tomorrow with my daughter and I’d enjoy meeting the 2 of you.

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Heteromorph
On 12/12/2017 at 11:12 PM, KimTexan said:

I do think it could be a rudist. @BobWillcould probably help with that. 

Here is another pic that I posted in my Cidarid post with a rudist in it. There are 2 more of the crescent shaped structures with a wavy edge in this pick. One is in the center and the other is just above and to the right of it. I’m not sure what the tube structure is. It is 5-6 inches long.F5893267-B48B-4DCF-98C1-0C0826CC3E15.thumb.jpeg.8f6243668f0785b1282675cb30c2eeab.jpeg

 

I was not there at Fossilmania on Friday. I was only there Saturday afternoon late and at the auction.

Do you and your mother attend the DPS meetings? If so I’ll be there tomorrow with my daughter and I’d enjoy meeting the 2 of you.

Blasted! I am just now seeing this! I saw that you were at the meeting on Wednesday when you posted the picture of the coprolite necklace and I was kicking myself that I didn’t get to say hi. Oh well, hopefully I could meet ya’ll at next month’s meeting. I have gone with my mother every time since the October meeting. I will PM you soon about meeting up.

 

Hopefully Bob Will and Bill Thompson can help with identifying the rudist like fossil and the echinoid respectively. Thanks for your help. I very much appreciate your pictures and your knowledgeable responses.

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Plax

Foreign rock is usually brought in by the dump truck load. To locate the source you can ask once the construction proceeds or go on google earth and look for nearby quarries. Rock is relatively cheap but expensive to haul so it is usually sourced nearby.

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Heteromorph
4 hours ago, Plax said:

Foreign rock is usually brought in by the dump truck load. To locate the source you can ask once the construction proceeds or go on google earth and look for nearby quarries. Rock is relatively cheap but expensive to haul so it is usually sourced nearby.

Thanks!

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Plax

you can also google "stone or rock suppliers, town name"

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Evans

Stereocidaris..... spectacular!

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Heteromorph
5 minutes ago, Evans said:

Stereocidaris..... spectacular!

Thanks!

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Heteromorph

I just heard back from Bill Thompson about @KimTexan's cidarid and my cidarid:

From Bill Thompson: 

 

"Beautiful echinoids.  Great finds.

Your cidarid:

"the ambs of T. hudspethensis have an elongated wart and one outer granule on each plate, whereas on T. borachoensis there are elongated warts, but no outer granule."

Your specimen does have the outer granule on each plate.

Your specimen looks to be:

Temnocidaris (Stereocidaris) hudspethensis  Cooke, 1955

 

The second cidarid (Kim's):

"Ambs extremely narrow, very flexuous.  Interambs very wide, made up of two rows of large prominent plates"

Kim's specimen looks to be:

Phyllacanthus tysoni  Whitney & Kellum, 1966

This echinoid is one of the very few that is not photographed in my book.  (The University of Michigan repeatly said that they were going to send me photographs of this specimen, but after waiting well over a year, I gave up.  I offered to fly to Michigan, but they insisted that they would send me the photos.)

Both are great finds.

Bill Thompson

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Heteromorph

More of my conversation with Bill Thompson:

 

 

Heteromorph:

Thanks for the information! Do you think that mine is from the Edwards Formation? According to your book, no T. hudspethensis specimens have been reported from that formation, and in fact none have been reported from the Fredricksberg Group as a whole.

 

 

Bill Thompson:

I cannot tell your formation for certain.  But looking at your photos, it could very well be Edwards.  Edwards is very hard, commonly has crystals, and has rudists.

What Austin Chalk echinoids have you collected?

 

Bill

 

Heteromorph:

Thanks for the information! 

I am am not really sure of the species of my Austin Chalk specimens. I have only found about four that I can be sure are echinoids, and only one of them is in good shape. Three of them appear to be the same species of irregular echinoid, while another one is larger than all the others but it is pretty beat up and needs a lot of preparation to see much of it. It looks like it could be a regular echinoid.

The irregular echinoid that I have that is in the best shape is still missing most of its test. It also could do with some preparation. 

I am a bit busy right now, but later today or tomorrow I will try to send you pictures of a few of my Austin Chalk echinoids for identification.

Again, thanks for all your help!

 

 

Bill Thompson:

In the Austin Chalk, I've collected Mecaster texanus, Phymosoma bybeii, and one Coenholectypus bullardi.

Bill

 

 

Heteromorph:

I will compare those to my echinoids and then get back with you soon.

——————————

 

I will start another thread for those echinoids.

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Heteromorph
14 minutes ago, JohnJ said:

Congratulations on a super rare find. The associated fauna all point to an Edwards Formation discovery...making this a rare cidarid specimen.

 

However, I would be reluctant to assign a species name to such an uncommon partial specimen. In hand examination might possibly provide further distinguishing characteristics pointing to an ID. You would also want that feature by feature examination to be compared to the scientific descriptions of known species. I prefer to use literature that has been peer reviewed by experts with a background in echinoid paleontology. 

 

You may want to review some of the references found on The Echinoid Directory.  Congrats again on your find.

 

@erose @Uncle Siphuncle

Thanks for the link and the informative response! I will be comparing my specimen to the ones on that website and in other literature. 

 

Do you think that I should try to contact an expert to do an in hand examination? 

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Heteromorph

Here are the only pictures of a Temnocidaris (Stereocidaris) hudspethensis specimen that I am a able to find pictures of online other than the pictures in Cooke's original 1955 description of this species. It is on Keith Minor's now defunct website cretaceousfossils.com. I am using the waybackmachine to acces it.

 

Aboral view

stereocidaris_hudspethensis_2new.jpg.27ea488d944e778703dfcaf1fdb6b884.jpg

 

Adoral view.

stereocidaris_hudspethensis_3new.jpg.02b82312a05f23929f96fa1c893b866d.jpg

 

Lateral view.

stereocidaris_hudspethensis_4new.jpg.8370a046466957579168df895daace57.jpg

 

 

 

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