Yellow Pencil Coral

Description:

(With some bicolor damselfishes cruising by.) Coral that forms hemispherical clumps that can be a meter or more across. Each colony is formed of densely packed, cylindrical branches with blunt, finger-like tips. In fore-reef habitats the branches are slender but in back-reef and lagoon habitats they are more robust and the clumps are larger. The hard skeletal material of which the colony is built as in most coral species covered by a thin layer of living tissue, the coenosarc. M. auretenra is unusual in this respect because, as the coral grows, the coenosarc progressively dies back on the lower parts of the branches leaving the skeleton bare, and only the tips of the branches are covered with living tissue.The corallites are from 1.1 to 1.6 mm (0.04 to 0.06 in) in diameter and have at least ten septa. This coral is yellow.

Habitat:

It is found in the Caribbean Sea and western Atlantic Ocean. This one was spotted in the dive site 1000 Steps in Bonaire.

Notes:

M. auretenra has been used as a study organism to predict the effects of ocean acidification on corals.