In wave-exposed or shaded, vertical and overhanging locations, the species is sheet-like, although a bushy form occurs in protected or deeper environments. Both forms can appear on the same colony.

Colonies are red encrusting sheets, mottled with pink or white, commonly under overhangs.

Each pore has a clear and well defined root-like web of canals radiating from it. The root network from each is not confluent with the roots of adjacent pores.

The name Monanchora barbadensis Hechtel 1965 may apply to the encrusting form shown here, if indeed the two are different species. The bushy form (which S. Zea considers to be the same species), has the older name of M. arbuscula. The sponge illustrated here is clearly the barbadensis form.