Corallum arborescent; stem presumably oblique (the present specimen consists of one stem and all its branches) 24 cm long. Branches wide spreading but not vertical to stem, some arcuate; tapering in upper half to acute apex; one branch 9.8 cm long, 1.3 cm across at base, with a short branchlet; another 10 cm long, 1.7 x 1.3 across at base has several branchlets. Upper surface crowded with unequally protruding corallites; lower surface slightly flattened, corallites low, distant. Terminal branchlets tapering, one 5 cm long has basal diameter of 1.1 cm; another 4 cm long, 9 mm across at base.

Axial corallite cylindrical with rounded edge, 2.5 mm diameter, 1.5-2 mm exsert; wall moderately thick, as thick as or little thicker than calicinal diameter, porous, finely costulate and echinulate. Septa in 2 cycles - primaries reaching or little short of radial midpoints, directive distinguishable only towards bottom of calicinal fossa where they widen; secondaries narrow, sometimes only ridges against wall.

Radial corallites unequal in height towards apical region, prominent ones very compressed, tubular, with elliptical calices facing upward, 1.5 x 2-2.5 mm across, 3.5 mm long standing about 45 degrees; wall porous but not fragile, costulate, finely echinulate on base, edge not rounded. Toward lower region, wall becomes thicker, echinules coarser, seriate or not, costules no longer evident, calices narrow, slitlike, apex well rounded. Among these prominent corallites are smaller, lower ones with thin wall, rounded calices, mostly nariform with calices facing in several directions – not always upwards. Septa in two cycles – primaries wide, directives distinguishable; secondaries narrow, sometimes not complete cycles. Lower down on branches and stems, radials become verruciform or low nariform with thicker walls and wider calices. Septa in 2 cycles with primaries very wide, almost meeting at center. Corallites on lower surface slightly protruding, calices rounded, septa in 2 cycles. No immersed corallites, except within some axils of branches.

Radials on upper branchlets tubonariform to almost labellate; upper wall slightly developed while lower wall may reach 2 mm, 1-1.5 mm across; wall latticelike but not very fragile, costate on younger corallites, costo-echinulate on older ones. Primaries very conspicuous because of width, especially directives which may converge at bottom of fossa, one usually wider than other. Secondaries very narrow, occasionally present..

Intercalicinal area very narrow on upper surface, dense, meshes narrower than threads; echinules in series may be present. Lower surface has intercalicinal areas wide; threads and meshes of reticulum longitudinal, with former wider than latter, rather bare, in sharp contrast with echinulous calicinal wall of corallites around.

Remarks: This coral is quite close to A. secunda as described by Dana and summarized by Brook. However no mention is made by Dana of the smaller corallites interspersed with the tall radials: Hoffmeister’s figure of Dana’s type also show no small corallites. Brook described his own specimen as having “radial corallites rather distant, ….. thin-walled ……Star scarcely developed……”. These do not characterize the present specimen. It does not fit A. secunda (Dana), nor Verill’s A. secundella nor A. nobilis (Dana).

Source: Nemenzo F (1967) Systematic studies on Philippine shallow water scleractinians: VI. Suborder Astrocoeniida (Montipora and Acropora). Part I - Text. Nat. Appli. Sci. Bull. 20 (1- 2): 1-141