Molluscs have a body cavity used for breathing and excretion, a rasping tongue or radula (except in bivalves), and a nervous system with two pairs of main nerve cords.
Cephalapod molluscs, squid, cuttlefish, and octopus, are among the most neurologically advanced of all invertebrates.
Squids have elongated bodies, large eyes, eight arms, and two tentacles. They are mainly soft-bodied but have a small internal skeleton. Squid can change color.
Berry's bobtail squid, Euprymna berryi
Cuttlefish have a unique internal skeleton, the cuttlebone. Cuttlefish have large W-shaped pupils, eight arms, and two tentacles with suckers. Cuttlefish communicate using visual signals involving color, posture, skin texture, and movement.
broadclub cuttlefish, Sepia latimanus
Gastropods are the most numerous molluscs.
Cowries are sea snails. Their shells are usually smooth, shiny, and egg-shaped.
[unidentified cowries]
Snails
[unidentified snail]
green top shell, Tectus pyramis
great coral worm snail, Dendropoma maxima
Bivalves are molluscs with laterally compressed bodies enclosed with a shell consisting of two hinged parts. Most are filter feeders.
boring giant clam, Ttidacna crocea
giant clam, Tridacna gigas
fluted giant clam, Tridacna squamosa
honeycomb oyster, Hyotissa hyotis
electric fileclam, Ctenoides ales
iridescent scallop, Pedum spondyloideum
[unidentified wing oysters]
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Last modified 30 July 2019