The body surface of Trochospongilla paulula is rather uneven, often featuring numerous irregular tubular projections, and it typically forms shallow cushions that range from nearly indiscernible to very striking encrustations (Soota, 1991). The oscula are prominent but relatively few. The skeleton is composed of well-defined vertical spicule fibers cemented together by spongin, along with irregularly arranged transverse fibers, resulting in a very hard consistency, sometimes brittle. The coloration varies from various shades of brown to predominantly dark brown. The megascleres are cylindrical, usually smooth, and nearly straight or weakly curved. Their dimensions range from 220-310 µm in length and 11-16 µm in width. Microscleres are absent. Gemmoscleres are birotulates, characterized by a cylindrical shaft containing two rotules at both ends. They are small to moderately large, with a slender shaft, and circular rotules that are unequal in diameter. The upper rotule is much recurved, forming a bow-like structure. The length, thickness, and diameter of the shaft range from 13-29 µm, 3-5 µm, and 9-16 µm, respectively. Gemmules are spherical, numerous, and distributed throughout the body. They are loosely attached by a skeletal network and unsheathed in the capsule of megascleres. The pneumatic coat is granular and comparatively thin, with gemmoscleres embedded in a single layer. The foramen tube is short, conical, and porous.