Unlike reef-building corals, many black corals (species in the order Antipatharia), do not possess the symbiotic algae, zooxanthellae, within their tissues. They are therefore not restricted to shallow, sunlit waters where the zooxanthellae can photosynthesise, and instead are able to inhabit deep and dark waters (2).
Little information appears to be available on the biology and life history of Antipathella species, other than the New Zealand species, Antipathella fiordensis (previously known as Antipathes fiordensis). A. fiordensis has separate male and female colonies (6), unlike the majority of corals which are hermaphrodite and thus possess both male and female reproductive organs. It is thought that this species reproduces primarily by spawning; eggs and sperm are released into the water column where fertilisation takes place. The fertilised egg develops into free-swimming larvae, which soon settles and attaches itself to the substrate, establishing a new colony. Spawning is thought to occur in mid- to late-summer (6). Genetic evidence has shown that A. fiordensis reproduces primarily by sexual means, but that some asexual reproduction also occurs. In a laboratory, they have been observed reproducing asexually via “polyp bail-out” (6), whereby polyps detach themselves from a colony, and form new colonies by normal budding (7). All black coral species are known to have a relatively slow growth rate and long lifespan (8).