A couple of years ago, when I was collecting Fundulus cingulatus, Leptolucania ommata and other various sunfish in the panhandle of Florida, I snapped this photo, because I thought it looked interesting. Now I wonder if this isn't one of your native Erio species.
I see what the problem is, when I copied the url of the photo it added http twice. I am on an IPAD2 and safari has limited copy and paste capabilities, so I can't fix this until I can get to a computer. In the mean time you can see the photo by going to photography, and its in the native album as erio maybe.
Almost certainly E. decangulare. Do you remember if the heads were hard? No obvious hairs on the scapes (peduncle (stem) supporting the heads? Looks too big to be a Lachnocaulon or any other Eriocaulon.
Thanks for the answers guys! I hope to get back to that spot and others next year and maybe I can answer your questions. At the time i snapped the photo I was just recording the way the environment looked. The Fundulus cingulatus were in mere centimeters or less of water, while the escambiae liked a little more water and the chrysotus were in deeper water.