Stratospongilla indica typically forms small, shallow cushions on solid supports, and its body surface is smooth. The oscula are minute, and the sponge’s skeleton is very ill-defined, consisting of slender spicule fibers. The live sponge has a rather hard but brittle consistency. The usual coloration is grey or light grey, but it turns green when zoochlorellae are present. The megascleres are more or less straight, cylindrical, and amphistrongyla (blunt or rounded at both ends). They are covered with minute spines, with dimensions ranging from 0.002-0.215 mm in length and 12-15 µm in width. Microscleres, specifically amphioxea (both ends pointed), are straight or slightly curved and covered with comparatively long and irregular spines. Their dimensions range from 40-47 µm in length and 3-4 µm in width. Gemmoscleres, also amphistrongyla (blunt or rounded at both ends), are feebly curved to straight, stout, and thickly covered with blunt spines. The diameter of the gemmules ranges from 0.47-0.50 mm.