The body of Dosilia plumosa has a bulbous shape with a lobose, uneven surface. The coloration is typically pale brown or greenish. Oscula are noticeable and small, and the dermal membrane is well-developed. The consistency of the sponge is somewhat soft and fragile. The megascleres in Dosilia plumosa are curved and fusiform. Those with pointed ends, known as amphioxea, appear smooth. The length and width of these spicules range from 0.40-0.60 mm and 15-20 µm, respectively. Numerous free lying spicules, identified as microscleres, are present. Among them, some have a central nodule bearing spicules in a stellate arrangement with 8-12 rays. These rays are smooth and terminate in a minute recurved distal spine. A few microscleres have granulated amphioxea with perpendicular and radiating rays, with lengths ranging from 0.15-0.20 µm. The spicule of the gemmule in Dosilia plumosa has strong, spined shafts. They are birotulates with rotules that are equal in size and shape. The margin of the spicule bears many recurved teeth and bounts. The length and width of these spicules range from 0.07-0.80 mm and 3-6 µm, respectively. Gemmules are numerous and range in shape from ovoid to subspherical. The pneumatic layer of the gemmule is granulated with minute spherical air spaces. The foramen tube is straight and short, with a diameter of 0.45-0.65 mm.