Occurrence at the Busselton Jetty: Cup corals are one of the only hard corals that inhabit the piles of the Busselton Jetty. Resembling anemones, the cup coral start to form on the jetty piles after 5 years as individuals but then divide and fan outward in branching lines to cover the pile in densely packed colonies.
Cup corals occur in the Order Scleratinia. Despite being hard corals, where the living polyp lays down a calcareous skeleton, they are a non-reef building species that inhabit shaded vertical surfaces down to depths of 238 metres. The individual polyps are arranged in a regular pattern, with the colonies often radiating out from a central point. The coral polyp is soft and delicate with a ring of tentacles in multiples of six, a characteristic of hard corals, and grows like tiny anemones inconspicuously across a hard substrate. Each tentacle is translucent with a white tip and the cup is often a light orange or pink. At night the animal extends its tentacles into the water current where they rely upon capturing zooplankton as food. The individual polyps grow to 5 millimetres in diameter. Cup corals occur on moderately exposed reef from Perth, WA and around the southern coast to Solitary Island, NSW, and around Tasmania.
Edgar, G. (1997) Australian Marine Life: The Plants and Animals of Temperate Waters, Australia
Morrison, S., Storrie, A. (1999) Wonders of Western Waters. Department of Conservation and Land Management, Western Australia
Morrison, S and P., Storrie, A. (2003) Beneath Busselton Jetty. Department of Conservation and Land Management, Western Australia