Large colonies, typically 4-6 cm in diameter, hemispherical or spheroidal in shape. Vertically sectioned colonies reveal the columnar subcolonies (fascicles) prolonged laterally at regular intervals to form platforms linking adjacent subcolonies and imparting a concentric structure to the colony (in addition to the radial structure imparted by the subcolonies). Each subcolony comprises a cylindrical bundle of zooids enclosed by exterior wall calcification that is smooth apart from longitudinal traces of interzooidal walls or faint growth lines. Platforms between subcolonies are formed by short zooids (?kenozooids) with apertures closed by terminal diaphragms.
Autozooids are very long (> 5mm) and tubular, with polygonal apertures averaging 0.20 mm in diameter that open at the distal of the subcolonies on the colony surface.
Gonozooids are uncommon. Their large chambers are attached to the exteriors of the subcolonies and appear to originate from the level of the platforms. They are roofed by smooth calcification (exterior wall), occasionally pierced by subcircular autozooidal apertures. Internally, septa-like vertical walls may subdivide the gonozooid incompletely. The ooeciopore has not been identified.