Meoma ventricosa (red heart urchins) (San Salvador Island, Bahamas) 1 (15958822907)

Kuvaus:

Description: Clypeaster rosaceus - sand dollar urchin (dead), washed ashore onto a rocky shoreline. Heart urchins (irregular echinoids) have somewhat globular skeletons (tests) composed of interlocking calcite plates and covered in short, fur-like spines. The skeleton is bilaterally symmetrical, not pentaradially symmetrical as in the sea urchins. The upper side of the skeleton has the pattern of a 5-petaled star - each petal is an ambulacrum. The mouth and anus are at opposite ends of the long axis of the skeleton. Heart urchins are infaunal deposit feeders - they consume bulk sediments, digest any organic matter mixed in, and excrete large quantities of sediments. Locality: beach landward from Snapshot Reef, Fernandez Bay, western San Salvador Island, eastern Bahamas. Date: 25 March 2007, 16:11. Source: Meoma ventricosa (red heart urchins) (San Salvador Island, Bahamas) 1. Author: James St. John.