ECHINOIDS AT VULCAN MINE
Echinoids are a class of echinoderms which includes the creatures commonly known as sea urchins, sand dollars and sea biscuits. Echinoids are found in deposits of any age in Florida. The ones found at Vulcan are from the Oligocene Suwannee Limestone and are around 30 million years old.
Phymotaxis mansfieldi This beautiful sea urchin is reasonably common, but it is always a goodz day at the mine if you find a nice one. They can be anywhere from .5 to 2 inches across.
Gagaria mossomi This urchin is less common than the Phymotaxis and tends to be smaller, but not always.
Clypeaster rogersi In some places in the mine these sand dollars have been reasonably common, but in general they are not. There is probably more than one species found at Vulcan. Oligocene Clypeasters can be as small as .5 inch or as much as 4 or 5 inches across.
Rhyncholampas gouldi This sea biscuit is by far the most common echinoid at Vulcan Mine, everyone finds a bucketful. They range in size from .5 inch to 2 inches across. Kinds of Rhyncholampas can be found in deposits of almost any age in Florida, but they are never as plentiful as in Suwannee Limestone.
Schizaster americanus This is a type of sea biscuit that is sometimes called a "heart urchin". This species is quite rare at Vulcan. It is usually less than an inch across.
Agassizia mossomi A very time sea biscuit that is also quite rare. About .5 inch across.