Corallum light, very porous looking; consisting of a basal plate supporting heavy vertical columns on central region. Plate concavo-convex, 15 cm across, creeping on dead portion of same coral; 8 mm thick at edge; upper surface showing concentric shallow wrinkles, with many low rounded protuberances on peripheral strip around base of columns. Columns massive; tallest one 7 cm high, 5 cm x 3 mm in cross section; tops dome-shaped, in some cases expanded, their surface also with low knobs similar to those on plate. Undersurface relatively smooth, peripheral area (2-4 cm wide) free of epitheca.
Calicles evenly disposed, not sharply cut from surrounding coenenchyme, flush with surface. Calices irregular or distorted in shape, 0.7-0.9 mm diameter; but for presence of septa and slightly larger size, they may be mistaken as meshes of the intercalicular reticulum. Fossa deep.
Septa very irregular in size and arrangement. Primaries usually far short of half radius points; less than size may be present and not equally distant. Directive not distinguishable. Secondaries very narrow; number and arrangement variable.
Intercalicinal reticulum very conspicuous, meshes wider than threads giving very porous appearance even to unaided eyes. Tubercles bristly, evenly disposed and almost even in height so that this coral has neat appearance; tall ones with side spinules limited to apical portion, their bases being smooth. One dome-shaped tops, tubercles give way to vertical lamellae with smooth surfaces. Reticulum on undersurface resembles that of upper but tubercles are lower, often reduced to single pointed spines.
