October 25, 2020: Bamboo Coral
Image courtesy of the NOAA Office of Ocean Exploration and Research, Northeast U.S. Canyons Expedition 2013. Download larger version (jpg, 277 KB).
Keratoisis-like bamboo coral with several brittle stars (Ophiuroids) on the branches, seen during the Northeast U.S. Canyons 2013 expedition. The branch on lower right has no tissue on it but tissue and short squat polyps can be seen on the other branches. At least one dark node can be seen through tissue on the branch on the lower left.
The common name “bamboo coral” refers to a more formal grouping of species that comprise the Family Isididae. All the species of this family of octocorals (corals whose polyps have eight tentacles) share the characteristic of having an internal skeleton that has short nodes – made of protein that is dark black or brown in color - alternating with longer internodes – made of calcium carbonate that is white in color. The effect of these alternating black nodes and white internodes reminded early biologists of bamboo, hence the common name.
From: A Wealth of Bamboo Corals.