Shell thin, snow white, of medium size (up to 40 mm). Shape usually oval. Protoconch paucispiral, flattened, with an angular carina partly concealed under suture. Adapical teleoconch whorls angulate with strong axial ribs on shoulder. All whorls densely covered with strong spiral cords, usually of equal size. Interspaces narrow and deep. Aperture ovate, adapically pinched, lip usually thick. Columella smooth, gently twisted. Siphonal canal short, broad, open. Operculum corneus, pale brown. Shape ovate, abapically pointed with terminal nucleus, filling aperture. Periostracum thin, smooth, greyish, well-adherent. Radula typically buccinid. Central tooth tricuspid with broad quadrangular base, lateral teeth tricuspid with large outer cusp and small middle cusp.

This new genus is characterized by a paucispiral protoconch, an oval shape with oval aperture and thickened lip (when adult), a smooth periostracum and a radula with a peculiar central tooth (base broad and quadrangular) and tricuspid lateral teeth with sharp cusps.
Manaria Smith, 1906 differs by the deep suture, the slightly flattened whorls with a weak subsutural truncation and by the presence of a columellar knob. The radula differs by the central tooth with longer cusps and narrower base and by the bicuspid lateral teeth.
Eosipho Thiele, 1929 differs in having smoother spiral cords. The radula differs by the central tooth with longer cusps and narrower base and by the bicuspid lateral teeth.
Recent species belonging to Serratifusus Harasewych, 1991 (type species: Fusus craspedotus Tate, 1888 from the Miocene of southeast Australia) have an almost identical radula, especially the shape of the central tooth, but differ by the columbariid shape of the shell.

Phaenomenella species are known from Taiwan and South China Sea only. They live in deep water (155-900 m) on sandy and muddy bottom. The following species are assigned to the new genus: Phaenomenella inflata (Shikama, 1971) comb, nov., Phaenomenella insulapratasensis (Okutani & Lan, 1994) comb. nov. and Phaenomenella angusta sp. nov. which is described below. No fossil species have yet been recognized as belonging to this genus.