''Lympnea truncatula'' is around 5-10mm long. It has a distinctive brown-black shell, with 5-6 spirals present on the outer surface. The first spiral is approximately half the total length of the snail. | ''Lympnea truncatula'' is around 5-10mm long. It has a distinctive brown-black shell, with 5-6 spirals present on the outer surface. The first spiral is approximately half the total length of the snail. |