Buchema melanacme is a species of sea snail, a marine gastropod mollusk in the family Horaiclavidae.

The upper half of each whorl is concave, and not crossed by the ribs, which are situated below.

Of the three spiral lirations which connect the ribs, the upper one is rather more slender than the others.

The small aperture is red and measures ⅓ of the total length of the shell.

[2] This marine species occurs in the Caribbean Sea off Saint Vincent.