Colonies encrusting, multiserial, sheet-like and often large with 1000 zooids or more. Seven to nine distolateral pore chambers per zooid may be visible in abraded colonies and at growing edges.
Autozooids are small, averaging 0.46 mm long by 0.32 mm wide, and elliptical in outline shape. The gymnocyst is normally narrow or absent. The relatively flat frontal shield comprises 12-19 costae (including the apertural bar), most often 13-16. Costae taper towards the centre of the frontal shield where they are fused. Between 1 and 6 (usually 3 or 4) intercostal pores are present, plus a larger papilla pore between the bases of the costae. The apertural bar forms a low suboral mucro, beneath which there is a median suboral lacuna. The orifice is D-shaped, broader than long, with 5 oral spine bases (4 in ovicellate zooids). Ovicells are subglobular and smoothly calcified with a complete ectooecium.
Avicularia are frequent, interzooidal, about half the length of an autozooid, with the pointed rostrum directed obliquely distally between the autozooids; the cross bar is uncalcified.