Corallum rather heavy, caespito-corymbose, laxly branched. Branches spreading, tapering gradually, horizontal; one branch 15.5 cm long, around 2 cm diameter at base, 1.5 cm at middle, 0.5 cm just below axial corallite; bearing proliferous branchlets on upper and lateral surfaces; lower surface not flattened, has very few, very low stunted branchlets resembling stumps or even verrucae. Upper branches terete, scarcely tapering except at apical region; often subdivided into 2 or 3 or more branchlets; tallest at medial areas (over 3 cm high), gradually diminishing towards tips; only slightly ascending except young ones which stand about 45 degrees from surface; 6 mm across at base, 4 mm near apex; do not stand parallel but project to all directions, except downward; apices mostly 1.5 cm apart.

Axial corallite conical or cylindrical, 3 mm across, less than a mm exsert; wall porous, less than calicinal radius in thickness, edge plane or rounded; costate. Septa in 2 complete cycles; primaries slightly short of half radius points, directives slightly distinguishable; secondaries about half as wide.

Radials on upper surface of branches immersed or even with surface; somewhat evenly disposed, around 2 mm apart, diameter, of calice around 1 mm. Those on lower surface unevenly disposed, 3-4 mm apart, around 1.5 mm calicinal diameter. Primaries wide, conspicuous almost convergent at base of fossa, while secondaries narrow, occasional.

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 areas markedly vermiculate all over, unevenly echinulate; threads and meshes about same width, the former parallel, running lengthwise.

Remarks: Remarks: The close affinity of this coral to A. Formosa is discernible except for the less prominent septa and the position of the radials.
Its closeness to A. robusta is rather obvious at first sight. However the present species appears very rugged because of the various positions and height assumed by the radial corallites which become appressed and thicker walled towards the basal regions of the branches.

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.