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A friend found out about my hobby of fossiking (particularly urchins) and says "oh, there are hundreds of the round urchins on my property, come on out!" So, I did and was initially disappointed to find out that what he thought were round urchins, were in fact algal fruiting bodies or porocystis globularis (as I discovered a while back when I first found the fossil forum, thinking I had some cool eggs....) So finding literally hundreds of these globularis was quite cool, but I wanted urchins! Now, also, there were urchins. Lots and lots and lots...of heart urchins. Which I like. A lot. But I also find them quite frequently where I am. I was wanting ROUND urchins! I havn't found but a few of those in my huntings. So I kept hunting. And was rewarded with a few small but nice phymosoma texanum round urchins. Yay!! And a mess of nice gastopods and bivlaves (some really adorable, yes, adorable, small deer heart clams) .All in all, a good days hunt!

Not much of a story-teller, so here are my better finds from my first trip to the glen rose formation (said to be the salenia zone) Whole gastropods and crushed heart urchins littered the ground all around the exposure, but i was particularly interested in a very ornate regular echinoid i'd never seen in person before, Leptosalenia Texana! My better finds: gastropods, neithea, tube worms, heart urchins, leptosalenia, porocystis algae balls, bivalve casts, and some oyster bits. My Leptosalenia: An unkown gastropod (?) covered in tube worms: And my bonus, two small coenholectypus approx. 10mm across

I have a couple of Coenholectypus from the Glen Rose which have the morphological characteristics of Coenholectypus nanus as described by Cooke, 1955. Some Cretaceous echinoids from the Americas. Geological Survey Professional Paper 264-E, page 96. In an aboral view, the periproct is clearly observed as a notch on the side of the test. It winds around the ambitus and terminates about three fourths of the way to the peristome. It is not Coenholectypus planatus. This is one of the specimens I wish to include in my book on Texas Cretadeous echinoids. However, I am just a little hesitant to classify it as Coenholectypus nanus as Cooke emphasizes that the examples from the Pawpaw rarely exceed 10 mm in diameter. This is remarkably close in size to a morphologically very similar species that Dan Woehr finds in the Boquillas. The ones I have are around 21.5 mm in diameter. Has anyone found examples in the Glen Rose that are similar in size to the ones that I have, or does anyone have a good idea as to what my examples may be if they are not C. nanus?

Earlier this year I ran across this tooth in the Glen Rose Formation of Central Texas. It is from about the middle of the formation (Unit 3, Upper Member) and would be Lower Albian in age. Note that it was found along with a few small round pychnodontid(?) teeth. For scale the red arrow is about 4.5mm in length. Not the small cusp between the large and outer cusp. There is a faint foramen on the lingual face. I will try and get sharper photos up if needed. The closest I have come is Cretolamna appendiculata only in that it fits the age and has a few characteristics that match. But all the images I find in books or online are for much younger specimens. Any ideas?

Found this in the Lower Cretaceous - Glen Rose Formation Great echinoid. Any help identifing would be appreciated. Bill Thompson Seguin, TX

January 2, 2010 The Lower Cretaceous Glen Rose Formation (Kgr) of Central Texas is roughly 110 million years old. Its classic exposures look like man-made steps or solid blocks that are occasionally interrupted with softer rock or marl. The formation is typically divided into upper and lower units by a layer of Corbula fossil clams. Just below this layer was the destination I wanted to find for my first fossil hunt of the year. It takes its name from the isolated occurrence of an ornate fossil sea urchin - the Salenia texana zone! A bright dawn had not yet thawed the frost when I headed to meet my friend, Bob. He was excited to show me a new quarry where he had found echinoids the previous month. When we arrived at the site, he oriented me to the most productive layers in the formation, and we started hunting the youngest strata. I immediately began to find fossils. Erosion of the shelf, we were searching, left fragments of 'heart' urchins, gastropods, and bivalves everywhere. I was trying to be selective, looking for the better preserved specimens, but it was hard to pass up an unusual oyster or clam. Oyster (Ceratostreon weatherfordensis ?) with the partial mold of the shell where it was attached Juvenile Arctica sp. clam Soon, Bob was calling out, "Spiny urchin!" with periodic repetition. He wryly commented, "I just seem to be a magnet for those things." Meanwhile, I gouged my elbow on rock as I crawled along the ground. Glancing to check the damage, I spied one of the small, prickly echinoids. It was just one of those small moments...that capture your love of the outdoors. The late morning light was perfect, and when I reached for the camera, a little heart urchin caught my attention. Even better. So, I digitally captured the two 'echies' before putting them in my box. We finished the morning and the rest of the layer with several more echinoids and a partial crab claw. Loriolia texana echinoid with Orbitolina texana foram Heteraster obliquatus echinoid among Orbitolina texana forams Loriolia texana echinoid Some finds after a little cleaning From this area, we moved down into the "zone". A hard limestone bench capped a six foot thick layer of softer rock. It weathered into chunky clay before a transition back to solid stone. Even within this bracketed strata, I noted some subtle differences in the coloration and hardness. But meanwhile, Bob had started finding echinoids while I was "getting the lay of the land". The marble-sized Leptosalenia texana were eroding with regularity from the top half of the zone. A small, disk-like foram, known as Orbitolina texana, littered the ground. Scattered among them were a variety of different gastropods and a non-fossil caterpillar. Leptosalenia texana with forams and gastropods Caterpillar Leptosalenia texana echinoids Bob previously mentioned that he had found a couple of plates (a part of an urchin's shell) from a very uncommon echinoid on his last visit. So, as we leaned against the wall of the formation, I asked him what else he remembered. He described them as being more whitish in their preservation than some of the other finds we were making; and when he said it, I thought of the variation in the rock I had seen earlier. We had already found fragments of the spines which the 'Salenia' urchins used to protect their shells; but I was not tracking them - we were tracking a cidarid echinoid! In the Glen Rose Formation, two species have been described: Phyllacanthus texanus and P. tysoni. So, I grinned when I saw part of a larger, bumpy spine sticking out of the rock. About that time, Bob suggested that we move over a short distance to a fresh spot. Hunting anything, with success, requires identifying and following certain clues. In the new spot, I put my suspicions to the test. A few feet below the caprock, I found a lighter layer that was somewhat hidden by runoff from layers above. I flaked away the debris to get a better look and immediately started to find several spine fragments! I announced my excitement, "Cidarid spines!" Echinoid spines 5 cm echinoid spine in matrix A slightly elevated heart rate accompanied the anticipation of following signs in the rock. Then, I had an adrenalin spike when Bob called out, "You need to look at this." He walked toward me, and in his hand were 3 connected plates of our cidarid urchin quarry. I showed him some of the spines and explained the "hidden" layer we could focus on. I thought we were close to our treasure, and he asked if I had "covered" the area just to my right. I told him, "No, go ahead" as I knelt down for a look at some of the spines eroding from the ground. "JOHN!" I turned to see him stand up beside me with a golf ball-sized, knobby echinoid in his palm! "You did it!" I yelled. "You really...did it! Way to go!" We stood a moment, looking at the rare urchin with a range of emotions. Then, he handed me his prize while he went back to get his camera. I put it back in the spot he picked it from and took a few photos. When he came back, more photos ensued...it was an amazing Texas find! Although I know quite a few cidarid urchins have been found through the years, I am personally aware of just five...including Bob's - certainly not a common discovery. Checking a few references later indicated he had found a Phyllacanthus texanus! Bob's discovery Phyllacanthus texanus echinoid Well, as you can imagine, the adrenaline of discovery had us quickly back in search mode. More spines were found. I ravenously scanned the layer we isolated. Then, my "heart jumped in my throat" when I spotted the partial test (shell) of another Phyllacanthus! So close...but not this time. My Phyllacanthus texanus partial test Late into the fading light, we searched to no avail. The cool wind and darkness ended our efforts, and we congratulated each other with our goodbyes. Hopefully, with some weathering and heavy rain, we will get another chance to track the rare fossil urchins of the Glen Rose.