About 7 inches from top to bottom, maroon-purple color. A few white micro crabs were found residing on the underside of the sand dollar. Found it under the sand while digging for conches and sea stars. Remained in general area near surface each day I came back for the next four days. Very much still alive. My one concern on the ID is that I’ve never seen M. quinquiesperforata at such a large size, not even fragments of the sand dollars I’ve found come close. I have found many other specimens of M. quinquiesperforata in the area, though.
Not great pictures, but blue and yellow spots very visible. Saw several in seas grass beds and near mangrove edges in ICW
Kingdom: Animalia
Name: Polycera hummi
Description: Small marine sea slug about 8mm in length. Brownish gray body covered in papillae and gills are visible on back of slug. Elongated papillae have blue and yellow bands and rhinophores are translucent grey. Found crawling on its muscular foot across a blade of sea grass.
Habitat: Coastal marine seagrass bed
Reference:Caribbean sea slugs: a field guide to the opistobranch mollusks from the tropical northwestern Atlantic (Valdes et al)