GLOSSARY - LANGUAGE OF SNAILS

Using keys requires the learning of some terms. The shell is oriented by having the mouth (aperture) at the bottom and the point (apex) at the top. In this position the mouth (aperture) will be on the right side of the shell.

Aperture – The opening or “mouth” of the shell.

Columella – The internal column around which the whorls revolve, the verticalaxis.

Columella straight – The columella continues without interruption tothe bottom of the aperture.

Columella truncated – The columella is cut off and does not continue uninterrupted to the bottom of the aperture.

Imperforate – Lacking an opening (perforation or umbilicus) on the bottom of the shell.

Lip reflected – The outside edge of the aperture is bent back or flared.

Lip straight – The outside edge of the aperture is straight, not bent back.

Mantle - The fleshy part of the animal.

Perforate – A small opening on the bottom of the shell.

Periphery – The widest part of the whorl. The part of the whorl most distant from the central axis (columella).

Protoconch – The whorls present when the snail emerges from the egg. In Helicophanta the protoconch is large and a different color from the remainder of the whorls.

Shape bulimoid – Shell is tall with the last whorl much broader than the prior whorl (fat shell). Aperture length is slightly less than half the shell height.

Shape conical – Shell is tall with the last whorl slightly broader than the prior whorl. Aperture length is less than 1/3 shell height.

Shape depressed – Shell is short with the height less than the shell width. Aperture height is more than half the shell height.

Shape fusiform – Shell is tall with the last whorl slightly broader than the prior whorl. Aperture height is almost half the shell height.

Shape helicoid – Shell height and width are approximately of equal length. Aperture height is more than half the shell height.

Shape skinny – Shell height is more than three times the shell width.

Shell height – The vertical length of the shell.

Shell width – The horizontal length of the shell.

Size large – The longest shell dimension greater than 30 mm.

Size medium – The longest shell dimension between 10 and 30 mm.

Size small – The longest shell dimension between 3 and 10 mm.

Size tiny – The longest shell dimension less than 3 mm.

Spire – The area from the top edge of the aperture to the top (apex) of the shell.

Umbilicus – A wide opening on the bottom of the shell.

Whorl – One complete turn of the shell.