[Ron Reefman]

You may be right, but I wouldn't bet on it as a sea cucumber or a tunicate as yet.

I was unsure just what it was when I collected it, but I was quite sure it wasn't illegal to collect per Sanibel Island, Lee County and State of Florida rules. I've collected and found lots of local sea cucumbers and they all have a different shape than this animal, they are more cigar shaped where this animal is very round with just a bit of cone shape at one end. Sea Cucumbers also have both feeding intake (with mouth parts) and an excrement end and act like worms. This animal has just one opening at the tip of the cone and both inhales and exhales water from this hole as if it were breathing.

It does look somewhat similar to a Sclerodactyla briareus, which is a cucumber, but it's more round and again, only one opening. Our best guess is that it's a Molgula occidentalis which is in fact a sandy-skinned tunicate. But I'm not 100% sure either.