Southern Caribbean Cryptic Scleractinian Reef Corals from Bonaire, N.A.

Abstract

At 14 sites along the west coast of the southern Caribbean island of Bonaire, Netherlands Antilles, 5045 living scleractinian corals in 1101 reef-growth-framework cavities over the depth range 12 m to 43 m were identified and counted. The sample comprises 28 hermatypic coral taxa, the ahermatype Tubastrea coccinea, and the hydrozoan Millepora alcicornis. Although there is no known fossil record of scleractinian reef corals in cavities, there is a record for the taxa living on the reef surface that also inhabit modern reef cavities. This permits speculation that the modern Caribbean cryptic scleractinian coral assemblage may have roots extending into the Tertiary, and at the family level, possibly into the Mesozoic. The common presence of 8 genera, amounting to 44% of the southern Caribbean cryptic coral assemblage, in reef cavities in both the southern Caribbean and the southwestern Pacific, supports the antiquity of the cryptic coral biota, by suggesting that at least those genera may have already been in cavities before the rise of the Isthmus of Panama.