Echinarachnius parma? Sand Dollar

I have had several sand dollars in box since childhood that I never knew the name of. Some of them have a gradient of brown across the surface. The shades of color remind me of the skin of marshmallow as it is being roasted over a campfire.

I cannot remember if I collected them on a beach in Massachusetts, North Carolina or Florida. They might have been given to me by our hosts on one of those trips as well. Unfortunately, digital cameras were not prevalent back then so no pictures were taken or these finds documented.

What I believe them to be are Echinarachnius parma sand dollar (echinoderm). It is also known as the Atlantic Sand Dollar. The species named by Lamarck in 1816 and the genus named by Gray in 1825.


https://en.wikipedia.org/wiki/Echinarachnius_parma