2. Class Gastropoda – “Stomach Foot”
-Extremely diverse
and numerous group
of animals
-Many are snails, but
there are species
without shells or
without coiled shells
3. Examples:
• Whelk – can be large, predators
• Conch – can be large, wind instruments
• Periwinkle – very common snail in our
area
• Nudibranchs – no external shell (interior
one made of protein)
• Limpets – not coiled like most snails;
conical or relatively flat
• Slipper Snail – can change from male
to female
• Abalone – used for jewelry
4. Anatomy
• Most have a spiraling shell
surrounding a soft bodied
animal
• Well defined head, ganglia,
no hearing
• Excellent sense of
smell/taste
• Gills to take oxygen from
water
• Trap door (operculum) to
protect animal when
withdrawn in its shell
• Mantle secretes the shell
• Bilateral symmetry
5. Habitat
• Benthic
– Motile
– Epifauna –live on
seafloor
– Have adapted to
almost every
marine
environment in the
world (i.e., rocks,
sand, mud, etc.)
6. Feeding
-Most are scavengers
using radula to
scrape algae off rocks
or decaying animal
matter from the
bottom
-Some are predators
Ex: cone snail
http://www.youtube.
com/watch?v=zcBm
MPJrrKk
7. Some of
Feeding cont.
predatory
snails feed by
drilling a hole
in another
Mollusk
Examples:
moon snail,
oyster drill
