Teretia nana
Teretia nana is an extinct species of sea snail, a marine gastropod mollusk in the family Raphitomidae.
Description
The length of the shell attains 4 mm, its diameter 1.5 mm.The small shell is turreted with a long, pointed spire. The convex whorls are depressed by a sutural border adorned with very fine arched growth lines. The body whorl is slightly toned down anteriorly. The spiral costulae are close together, round, larger on the ventral part of the body whorl, smaller anteriorly. Two small cords run over the anterior part of the sutural border. The outer lip is frail, wrinkled, arched. The columella is smooth, excavated posteriorly, almost straight at the origin of the siphonal canal, which is short and wide.