A Guide for Terrestrial Gastropod Identification - University of ...

Discoidaal
– a wider-t than-high, veery
flattenedd,
disc-like shhell
shape of
certain taxa
(e.g.,
Helicodisscidae).
Foot – thhe
flat muscu ular surface oof
the snail’ss
body uponn
which it craawls.
Globose
overall
– a shell sha ape similar too
heliciformm,
but with a higher spiree
and more roounded
shappe
Growth llines
– transv verse ridges on the shell’s
surface, fo formed durinng
the snail’ss
growth.
Head – thhe
anterior region
of the snail’s bodyy
that contains
the tentaccles
and mouuth.
Height – the height of o the shell iss
measured ffrom
the apeex
to the mosst
basal part of the shell, ,
parallel tto
the colume ella.
Hirsute – describes a shell that haas
hairs on thhe
surface oof
its periostrracum.
Keel (of the shell) – a sharp edgee
of the peripphery
of the shell presennt
in certain ttaxa.
Keel (of the tail) – a ridge on thee
tail present in certain taaxa.
Lip or appertural
lip – the rim of thhe
aperture oof
the shell, either sharpp
or thickened
dependingg
upon the species.
Lirae – raaised
lines on o the shell’ss
surface thaat
run in a spiiral
directionn.
Malacoloogy
– the stu udy of molluusks.
A scienntist
who stuudies
molluskks
is called a malacologist.
Mantle – one of the features f that defines the phylum Molllusca
as a taaxon;
this is a tissue thatt
covers thhe
visceral or rgans of the animal. In ssnails,
it is loocated
withiin
the shell, aand
only thee
edge of thhe
mantle is observable at the apertuure.
For sluggs,
the mantlle
is located dorsally behhind
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