Megastomia conoidea is a species of sea snail, a marine gastropod mollusk in the family Pyramidellidae, the pyrams and their allies.

The white shell is solid, polished and with microscopic growth lines.

The interior of the outer lip is ridged, terminating in small tubercles within the mouth.

[3] (Description of Odostomia sicula) The white shell is solid and polished.

The interior of the lip is ridged, terminating in small tubercles within the aperture.