Shell biconic, rather large for the genus, 9-11 mm., and also with all the characteristic features of the subgenus. Protoconch with about 1,5 translucent whorls having a brown tip, sometimes with an internal brown streak. Teleoconch whorls slightly rounded, sutures distinct with lightly shouldered whorls. Colour beige to dark brown, sometimes with white spots or a continuous light coloured band, above the suture. Sculpture of axial ribs and spiral chords on the first three teleoconch whorls, forming small beads at intersections. All other teleoconch whorls only with spiral chords present. There are 6-8 chords on the penultimate whorl and 24-26 on the body whorl. Columella with 2 folds, the upper one the largest. Outer lip thin and sharp, but thickened internally, with one slightly large and about 18 smaller dentitions internally. Animal unknown.
Material studied
Holotype, h= 11 mm w= 4.5 mm Punta Engano, from tangle nets set on coral, 30-35 m Philippine Islands., 1996, BMNH.
Distribution: The Philippine Islands.
Discussion
This species attains a size of over a centimeter and is one of the largest for the genus. A few specimens have a rather more stubby shell with a beige background colour, but the sculpture is similar in all respects. There are no other species, presently known from this subgenus at the Philippines and it is probably the species figured by Springsteen & Leobrera (1986: PI. 79) as Mitrolumna species.