Compared to the other species, disk unusually small, disk margin length much smaller and cranium narrower compared to SL; eyes also smaller. Tubercles along edges of disk and sides of tail dorsoventrally flattened and closely adjoining, forming a thin, continuous saw-toothed ridges; those on sides of tail even, extending on either side of the caudal fin like keels. Cephalic lateral line scale counts: preopercular 2; subopercular 5; dorsolateral branch of subopercular 3; supraorbital 3-4. Lateral line scale counts on body 0 (nothing detectable dorsal surface of disk); tail 12-13. Esca slightly exerted from the illicial cavity, tipped forward more than 90°. Gill rakers as thin, triangular plates perpendicular to gill arch, each with tiny teeth clustered distally. Paired fins relatively small, pectoral pedicels joined to body by membrane. Dorsal and anal fins small with last ray of dorsal attached to body by membrane (Ref. 40825).