Diagnosis: Shallow groove parallel to the columella and bending 90 close to the calyx, to form a deeper, ring−shaped groove. Description: Shallow grooves (1 mm maximum in depth) that run more or less in parallel to the axis of the columella from close to the base of the corallite. They turn a sharp 90 to the left when reaching a point a few millimetres from the edge of the calyx, where they deepen (to some 2 mm) and run almost the whole of the perimeter of the corallite, thus taking on the appearance of a branding iron.