The body surface of Trochospongilla philottiana is relatively even but distinctly hispid, forming moderately large flat encrustations. The oscula are inconspicuous and few in number, and the live sponge has a hard but relatively brittle consistency. The coloration of the sponge is in the range of pale yellow to light brown. The megascleres are slender, weakly curved, and more or less uniformly covered with small conical spines. Their dimensions range from 0.17-0.19 mm in length and 0.009-0.010 mm in width. Microscleres are absent. Gemmoscleres are birotulates, characterized by a cylindrical shaft containing a rotule at each end. The shafts are smooth and slender, with circular rotules that are unequal in diameter. The upper rotule forms a bow-like structure. The length and thickness of the shaft range from 14-16 µm and 3-4 µm, respectively. Gemmules are small, spherical, and numerous, situated at the base of the body. They are usually surrounded by a capsule of normal megascleres. The pneumatic coat is granular and very thin, with gemmoscleres embedded in a single layer. The foramen tube is short, conical, and porous. Gemmules have a diameter ranging from 0.26-0.32 mm.