Tara Oceans scienceResearch Teams Structurally simple and
functionally complex metazoans, scleractinian (hard) corals have
been leaving track of their carbonatic skeletons in the fossil
record for approximately 240 mya. Half of the known extant taxa
are symbiotic with photosynthetic dinoflagellates and represent
the main builders of tropical coral reefs, the most diverse
coastal ecosystem on the planet. The economic and social
importance of tropical coastal ecosystems in general and of
coral reefs in particular is widely recognized and so is their
vulnerability. Quantifying the diversity of coral reefs is no
easy task even for taxa like hard corals, and their evolutionary
history is still under debate. Besides its intrinsic importance
as such, the species problem in scleractinian corals has
important downfalls on several aspects of coral reefs biology,
ecology, biogeography and conservation. In fact, molecular
phylogenies and traditional taxonomy and systematics of hard
corals based on morphology are, to a la