Corallum explanate, foliaceous (presumably only a part of a saucer-shaped corallum is at hand); irregularly folded, 29 cm x 21 cm in diameter; attached by a comparatively small base, 1 mm thick at edge, around 18 mm at center; unifoliate. Concentric arrangement of collines quite distinct, except at few places where surface very uneven. Collines vertical to surface, 2 mm or les high, usually less than 2.5 mm wide from valley to valley; apex almost acute, triangular in section. Valley narrow, 2-2.5 mm across.
Septa thinner or as wide as loculi; in some places wider and narrower ones alternating but this is not discernible in other places; borders sharp, crinkled, surface laxly covered with fine spines; usually 20 to a half cm.
Columella flat, disturbed here and there by the expanded lower ends of the septa.
Lower surface very vesicular, the vesicles obscuring the costae, except at the narrow peripheral strip where very fine costal ridges can be recognized, obsolete on some portion of the strip. Low smooth costae usually alternating with higher spiny ones; the higher ones usually with crinkled edges, their spinules irregularly disposed.
