Corallum light, ramose on moderately large base; basal surface with thin epitheca. Common stem palmate, 4 cm greatest diameter; branches short; tallest 4.5 cm high, 2 cm across at base. Terminal branchlets also stout with well rounded apices, up to 2 cm across at base.
Corallites slightly angular to subcircular, 2-2.5 mm across, around 2 mm deep. Younger corallites toward tips of branchlets have relatively thinner walls, lace-like with pores wider than intervening strands; mural edge topped with 7-9 conical or triangular spines. The older corallites on stem have much thicker, still perforate walls topped with heavy spines, almost tetrahedral in form. Younger corallites deeper than older ones.
Septa represented by triangular spines, far short of radius midpoints toward calice but longer, convergent at bottom of fossa. In older corallites, septa become heavy triangles convergent at center, shorter septa toward calice scarce. Septa all smooth. Cycles indistinguishable because of irregularity in size and arrangement.
This species is unique because of its triangular septa and heavy mural spines which become tetrahedral in old corallites.
