August 2nd, 2018 Yankeetown Echinoids ID

[Sacha]

I took a quick trip to Yankeetown, FL this week because, although I've been there a number of times, it is one of the few locations I know of that isn't under water this year. I screen sifted for a couple hours and got some nice examples of echinoids already in my collection. I'm paying more attention to these sand dollars and sea biscuits since the variety in my collection is growing and my contribution to the Univ. of FL Museum really piqued my interest. I was hoping I could get proper species names for the specimens in the following photos. These would be from Ocala Limestone, Inglis Formation. First the small sand dollar. These are quite common, in good condition and rarely larger than the larger on shown.

 

Next is the small sea biscuit. I think there are 2 different species in the picture, but the more oval one is probably in to poor condition to ID. The other inflated obloid ones are not that common and are what I'm primarily hunting for when I go back to these islands with the exception of the still allusive sea urchin.

 

 

I appreciate the help. Thanks for your time.

 

[Harry Pristis]

 

There are two or three nickel-size echinoids there.  You almost have to have them in hand to ID them reliably.  With that demurrer, here are some I've identified:

 

A-1  Echinolampas appendiculata Emmons
         (Eocene, North Carolina)
 A-2  Arbacia sloani (Pliocene, So. Car.)
 A-3  Arbacia sloani (Pliocene, So. Car.)
 A-4  Neolaganum durhami Cooke
         (Eocene, Florida)
 
B-1  Schizaster ocalanus Cooke
 B-2  Schizaster ocalanus Cooke
 B-3  Durhamella (Laganum) ocalana
 B-4  Durhamella (Laganum) ocalana
 
C-1  Oligopygus phelani Kier, 1967
         (growth series)
 C-2  Neolaganum durhami Cooke
 C-3  Weisbordella cubae (Weisbord)
 C-4  Durhamella (Laganum) ocalana

 

In the second of your images, the center three egg-shaped specimens appear to be Agassizia floridana.  The tiny example in the lower right MIGHT be Fibularia vaughni, but I can't say for certain from the image.

 

[Sacha]

Thanks Harry. Your images provide a much better guide than the old sketches I used to have.