Shell up to 2.3 mm in length, ovoid but with tendency to a triangular form because the spire is very low and the posterior part of the last whorl is more separate from the axis of the shell: thus, it looks like a triangle with the apex on the siphonal canal. Shell milky white in colour, but translucent. Never with colour bands. Aperture elongated. Outer lip thickened, denticulate in its inner part, being these denticles smaller, elongate towards the interior and almost disappeared near the posterior part. Columella with 5 folds, decreasing in size posteriorly. Siphonal canal short and wide.
The animal is very similar in colour to that of the G. decorfasciata: animals of both species studied together at the same time were not differentiated. Only after the introduction in alcohol. G. albotriangularis keeps the black colour of the soft parts, which is lost in G. decorfasciata

G. albotriangularis is different from other similar species (except G. decorfasciata) by the same reasons exposed for the animal colour of G. decorfasciata, but firstly because of the milky white colour of the shell and its characteristic triangular profile. By the latter it can easily be differentiated from G. decorfasciata with which it lives sympatrically. Shells have difference in the external lip: many small teeth (up to 17) in G. decorfasciata compared with 6-7 bigger teeth in the lower part in G. albotriangularis.
G. philippii has a similar shell but this species is not so wide in the shoulder and the shell is more translucent; it has usually dark blotches on the foot, when the animal has dark blotches visible through the shell in transparency.

Ghana