Its colonies are arborescent, with trifurcately branching stolons of approximately 0.5 mm in diameter. Zooids are sac-like and arranged along 2 sides in rows. Zooids measure approximately 0.4 0.6 mm in height. The lophophore has a diameter of approximately 0.320 mm, and bears 8 tentacles. A large gizzard is present.
Young colonies have transparent stolons.
Calcium carbonate is absent in exoskeletons of this species. Z. verticillatum is widely distributed in warm temperate and tropical waters in the western Atlantic and the Caribbean. Z. verticillatum has the greatest biomass of any bryozoan species in the IRL, and develops large populations throughout the summer. It is possible that this species, due to its ability to filter particulates from large volumes of water, contributes to the overall health of the IRL ecosystem. Stolons generally measure 0.5 mm in diameter, individual zooids measure 0.4 0.6 mm, and tentacles of individual zooids measure approximately 0.3 mm in diameter.