Table Coral 401

Acropora cytherea is a stony coral which forms horizontal table like structures. It occurs in the Indo-Pacific Ocean in areas with little wave action, favouring back reef environments from 3 to 20 m (10 to 66 ft) depth. Acropora cytherea is a colonial species of coral that grows in large horizontal plates. These are formed of many tiny branchlets growing vertically or at an angle and others growing horizontally to extend the colony. They may branch and link together and near the centre the plates may become a solid mass of joined branchlets. The surface of the table coral is covered by a thin layer of living tissue. This has a rough surface and contains zooxanthella, symbiotic, unicellular, photosynthetic algae. These give the table coral 401 its cream or pale brown colour (occasionally pale blue).^[2][3] The calcium carbonate skeleton is secreted by many small polyps which are joined together through an interconnecting network of channels inside the skeleton. At night, and sometimes during the day, the polyps protrude from the skeleton and extend their tentacles to feed. At other times, they contract back into the safety of the skeleton.^[4] In older specimens, particularly those exceeding 2 metres (6 ft 7 in) in diameter, the regular structure sometimes breaks down near the centre and there are growth anomalies. It has been found that these are not deleterious to the survival of the coral and may be caused by stress factors such as raised sea temperatures.  Acropora cytherea or table coral 401 is one of the most plentiful members of the genus Acropora. It is found in the Indo-Pacific Ocean from the Red Sea and the east coast of Africa to India, the China Sea, Japan, Australia, Micronesia and Hawaii. It is found below low tide mark in clear shallow water with little wave action, in lagoons and upper reef slopes and back reef slopes.