Features

Description

Protoconch

Larval shell at the apex or point of the tubular shell

Columella

Central axis of which new gastropod shell coils around in a conical fashion during growth.

Whorls

Each complete revolution or coil of the cone around the columella

Body Whorl

The largest and outer most whorl at the base of the cone housing most of the animal’s visceral mass and head-foot.

Spire

Region formed by the remaining spire whorls that rises above the body whorl

Suture

Line of contact between 2 whorls that is tightly cemented

Posterior Canal

Posterior end of the aperture margin

Umbilicus

Cavity up the central axis which appears at the base of a shell as a hole

Aperture

Opening of the shell

Outer Lip

Outer edge of the aperture

Inner Lip

Edge lying against the rest of the shell in the aperture

Anterior Canal

Indented anterior margin of the shell aperture

Operculum

Not part of the shell. Door-liked horny disc on the posterior dorsal surface that closes the aperture when the head-foot is retracted