Small Coenholectypus From The Glen Rose

[Solittletime]

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?

[Uncle Siphuncle]

bill do you have pics, and have you looked at c. ovatus?

[erose]

You can see the species C. ovatus (Whitney & Kellum) in this paper:http://www.academia.edu/3248494/Echinoid_diversity_preservation_potential_and_sequence_stratigraphical_cycles_in_the_Glen_Rose_Formation_early_Albian_Early_Cretaceous_Texas_USA

I have yet to find an ovatus that I am 100% sure of, but I have many smaller Coenholectypus from the Glen Rose that need cleaning. They also write about C. planatus from the upper member that are more like the typical C. planatus from the Fredericksburg Group above. And of all of mine, of all sizes from the Glen Rose and the Walnut Formations the periproct has a wide range of positions, yet they otherwise appear identical.

Good luck sorting this one out.