Diagnosis: Helicoidal groove running around the corallite. Description: The trace consists of a groove that begins close to the base of the corallite and ends at the edge of the calyx, following an helicoidal, clockwise, sometimes irregular, pattern around the skeleton. Between one and two complete turns are made and it may present one or two short branches. Usually, the deepest part of the groove corresponds with the nearest to the coral calyx, and it is never deeper than 2 mm.