Basilissa superba is a species of extremely small deep water sea snail, a marine gastropod mollusk in the family Seguenziidae.

Sculpture: There are about twenty delicate threads, very nearly but not quite regular in thickness or distance, on the upper part of the body whorl.

They are flexuous, marking the lines of growth, rather stronger, more regular and more distant than the spirals, which run over the top of them and form little white nodes at the crossings.

The aperture is perpendicular, rhomboidal, the basal and palatal lines being parallel, the other two are somewhat diverging and curved, broader than high.

The outer lip is sharp and thin, not patulous, not descending, with a shallow open sinus below the suture, then, about the middle of the whorl, it advances with a rounded sweep, retreating sharply across the carina to form the open rounded basal sinus toward the outer edge of the base.

Within, besides the two spiral lines, there are slight longitudinal striations, and the inner edge of the whorls twines like a staircase round it, but concealed by the overcurve of the columellar lip.