Shell small, needle-shaped, with blunt, bulbous apex. There are 9-10 tumid whorls of which two belong to the protoconch and are smooth. Sutures are rather deep. Last whorl occupies 35-40 % of shell height. Ornament of many delicate costae with spiral ridges in the intervening spaces. There are 10-11 spiral ridges on the more basal whorls, fewer up the spire. They are usually absent from the subsutural part of each whorl and from the base of the last one. The basal whorls have thirty or more costae each, the others about twenty. The costae are narrow and flexuous and extend to the base of the last whorl. Aperture is small and occupies about 20 % of shell height. A groove lies along the columellar lip, but is without an umbilicus at its end.
Up to 2 x 0.5 mm.
The head has a narrow snout, the mouth lying at its tip and two tentacles at its base, each with a basal eye; the tentacles diverge markedly to right and left as the snail creeps. The mantle edge has a tentacle on the right. The foot is slender, with its anterolateral corners tentaculiform, its posterior end pointed and carrying a thin operculum. The flesh is white, with dark brown on the snout and the sides of the head and along the gill and rectum.
Muddy and sandy bottoms and on weeds from LWST to about 30 m deep.
From the Mediterranean north to Norway (Distr. G. albida). There are many records from all parts of the British Isles but most refer to dead shells. The animals are either rare or overlooked because they are so small or both.