December 29, 2021: Purple Coral
Image courtesy of NOAA Ocean Exploration, Deep Connections 2019. Download larger version (jpg, 497 KB).
Clavularia, here seen during the Deep Connections 2019: Exploring Atlantic Canyons and Seamounts of the United States and Canada expedition, is a stoloniferous octocoral that grows in ribbons and mats over rock or skeletons of coral or sponges. The purple color is due to a pigment in the soft tissue and the white is reflections from sclerites. Sclerites are part of the microskeleton of an octocoral that provide support and protection. Because they are so varied in shape, size, and abundance in the tissue, sclerites are used by taxonomists—specialists in the description, naming, and identification of species—to help sort out the diversity of octocoral species.
From: What is a Sclerite?.