About Heteropsammia cochlea (Spengler, 1781)
Heteropsammia cochlea (Spengler, 1781), commonly called the walking dendro, is a small solitary free-living coral that is not attached to the seafloor, and grows no more than 2.5 cm across. It is made up of one or two corallites, which have a figure-eight shape when viewed from above, a trait that makes this species easy to identify. Its base, which contacts the seafloor, is roughly circular; it is either flat or slightly keeled depending on the type of substrate. An orifice on the base holds a commensal worm from the family Aspidosiphonidae. The whole coral is typically yellowish, grayish, or greenish. The polyp tentacles can be seen extended, especially at night. This species is widely distributed across tropical and subtropical waters of the Indo-West Pacific, ranging from the eastern coasts of Africa (including the Red Sea) to the Philippines, and from southern Japan to Australia and New Caledonia. It inhabits the seafloor on flat or gently sloped bottoms, at depths between 1 meter and 40 meters.
