Mollusks

Phylogeny Platyhelminthes Porifera Mollusca Chordata Arthropoda Annelida Cnideria Nematoda Echinodermata pseudocoelom segmentation acoelom Protostome: schizocoelem Deuterostomes: eucoelom radial symmetry bilateral symmetry no true tissues true tissue Ancestral Protist

Phylum Mollusca More than 500,000 known species Class Polyplacophora Gastropoda Class Bivalvia Class Cephalopoda chitons Snails Sea slugs nudibranchs Squid Octopus Cuttlefish Nautilus clams More than 500,000 known species

Body Plan Three main parts: Muscular foot- for movement Visceral mass- contains most of the internal organs Mantle cavity- houses gills

Generalized Mollusc Anatomy mantle visceral mass foot

Feeding Types Grazers (radula- scraping tongue) Filter feeding Egg eaters Active predation

Kingdom Animalia Phylum Mollusca

Class Polyplacophora chiton

Subclass Opisthobranchia Class Gastropoda Subclass Opisthobranchia Spanish Dancer (nudibranch) & egg mass

nudibranchs Phistella Phylum Mollusca Class Gastropoda nudibranchs Phistella

nudibranchs Nembrotha kubaryana

nudibranchs Chromodoris annae Halgerda batangas Cuthona sp.

Class Gastropoda periwinkle Opihi Cowery Cone snail

Epitomium

Triton’s trumpet

pterapods

Class Bivalvia

oyster

Class Cephalopoda

Class Cephalopoda

Class Cephalopoda http://www.youtube.com/watch?v=U2s3C0lkQE0 http://www.youtube.com/watch?v=NR53smpV_xg

Class Cephalopoda

Octopus Intelligence http://www.youtube.com/watch?v=GQwJXvlTWDw Start at 2 minutes

Mimic octopus from Indonesia flatfish Sea snake lionfish http://www.youtube.com/watch?v=H8oQBYw6xxc

Blue-ringed octopus Highly venomous                                       The brilliantly colored blue ringed octopus (Hapalochlaena lunulata) hunts using a venom so powerful it can kill a human Highly venomous