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DescriptionPorolithon pachydermum (calcareous red algae) (San Salvador Island, Bahamas) 1 (16055272995).jpg
Porolithon pachydermum (Foslie, 1904) - "reef cement" (calcareous red algae) on patch reef.
Porolithon is a pinkish to pale-pinkish, calcareous crust that occupies reef crest and near-reef crest facies, where high-energy waves, intense sunlight, and occasional desiccating conditions (from low tides) occur. It has been recognized as a very important reef-building organism. Porolithon crusts frequently have many subcircular openings, resulting in a “swiss cheese”-like appearance. These are borings produced by the chiton Choneplax lata (malacos.chez.com/htm/C08G2.HTM) (Mollusca, Polyplacophora).
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