Colonies planar or multiplanar, bushy, arborescent, laterally branched, pinnately branched, dichotomous or with long flexible branches without occasional branch anastomosis. Branches and branchlets upward bending almost parallel, and with about the same thickness all along, frequently with slightly enlarged tips. Coenenchyme moderately to very thick (compared to other plexaurids) with a circle of longitudinal canals surrounding the axis and dividing the coenenchyme into a thin inner layer or axial sheath, and a thicker outer layer. Polyps fully retractile within prominent calyces longitudinally and closely placed and at all sides of the branches. Calyces prominent, shelf-like or tubular, with prickly projecting spindles, longitudinally arranged, imbricate or not. Anthocodial sclerites mainly small spindles, in weakly differentiated transverse collaret and points below the tentacles, or just with some sclerites scattered along the neck zone of the polyp. Sclerites of the outer coenenchyme mostly long, unilateral spinous spindles, often massive, sculptured on inner surface by crowded complex tubercles and on outer surface by simple spines or prickles, and in some species with a few more or less prominent coarse, prickly projections. Axial sheath composed of capstans, spindles, or oval forms. Sclerite colours white, various hues of yellow, amber, orange, purple and red. Anthocodials with lower colour hues.