Phylum MolluscaPhylum: Mollusca•Very successful phylum•Name = soft-bodied•Many have external CaCO3shell•Cephalization: development of head region•Several specialized organs•Mantle •Foot •Radula•Seven classes (we talk about three)Feature of the gastropodsKingdom: AnimaliaPhylum: PoriferaPhylum: CnidariaClass: HydrozoaClass: ScyphozoaClass: AnthozoaPhylum: CtenophoraPhylum: PlatyhelminthesPhylum: NemerteaPhylum: GastrotrichaPhylum: KinorhynchaPhylum: PriapulidaPhylum: NematodaPhylum: EntoproctaPhylum: EctoproctaPhylum: CycliophoraPhylum: PhoronidaPhylum: BrachiopodaPhylum: MolluscaClass: AplacophoraClass: MonoplacophoraClass: PolyplacophoraClass: GastropodaClass: ScaphopodaClass: BivalviaClass: CephalopodaPhylum: SipunculidaPhylum: EchiuroideaPhylum: PogonophoraPhylum: HemichordataPhylum: ChaetognathaPhylum: AnnelidaPhylum: ArthropodaSubphylum: ChelicerataClass: MerostomataClass: PycnogonidaSubphylum: CrustaceaClass: BranchiopodaClass: OstracodaClass: CopepodaClass: CirripediaClass: MalacostracaPhylum: EchinodermataClass: AsteriodeaClass: OphiuroideaClass: EchinoideaClass: CrinoideaClass: HolothuroideaPhylum: ChordataSubphylum: UrochordataSubphylum: CephalochordataGlaucus Atlanticus: Pelagic Gastropod (Heteropoda) that eats Portuguese Man O' Warshttp://www.hartleybermuda.com/invertebrates.htmlwww.coral.org/node/2586www.linein.orgSea Slugs (Nudibranchs)seaslugforum.netwww.wildlifeextra.comSolar Powered!Scientists discover 5 new species of sea slugs from the Tropical Eastern Pacific22/06/2007 00:00:00 The Tropical Eastern Pacific has an extremely high rate of endemism among its marine organisms and continues to yield a wealth of never-before-described marine animals to visiting scientists at the Smithsonian Tropical Research Institute in Panama. The most recent discovery is FIVE new species of sea slugs found between 2001 – 2005.It took Alicia Hermosillo (researcher at the Universidad de Guadalajara in Mexico) and Angel Valdes (assistant curator of Malacologyat the Natural History Museum of Los Angeles County) two more years to identify the animals in the new collection by comparing them to existing collections, consulting specialists and using a scanning electron microscope to examine the jaws and other hardparts of the nudibranchs that distinguish species. NudibranchsNudibranchs—a group of mollusks lacking outer shells— have developed sophisticated chemical defense mechanisms, which is particularly important because promising industrial and medicinal products have been isolated from known species. New species may provide cures for diseases that are currently untreatable. This was part of the formal project ‘Phylogenetic Systematics of Nudibranchia,’ sponsored by a National Science Foundation grant to Terrence M. Gosliner, senior curator for Invertebrate Zoology and Geology at the California Academy of Sciences and to Valdes. The microscope work also was supported by the NSF through a grant to Valdes and collaborators.Kingdom: AnimaliaPhylum: PoriferaPhylum: CnidariaClass: HydrozoaClass: ScyphozoaClass: AnthozoaPhylum: CtenophoraPhylum: PlatyhelminthesPhylum: NemertinaPhylum: GastrotrichaPhylum: KinorhynchaPhylum: PriapulidaPhylum: NematodaPhylum: EntoproctaPhylum: EctoproctaPhylum: CycliophoraPhylum: PhoronidaPhylum: BrachiopodaPhylum: MolluscaClass: AplacophoraClass: MonoplacophoraClass: PolyplacophoraClass: GastropodaClass: ScaphopodaClass: BivalviaClass: CephalopodaPhylum: SpinuculaPhylum: EchiuridaPhylum: Pogonophora Phylum: HemichordataPhylum: ChaetognathaPhylum: AnnelidaPhylum: ArthropodaSubphylum: ChelicerataClass: MerostomataClass: PycnogonidaSubphylum: CrustaceaClass: BranchiopodaClass: OstracodaClass: CopepodaClass: CirripediaClass: MalacostracaPhylum: EchinodermataClass: AsteriodeaClass: OphiuroideaClass: EchinoideaClass: CrinoideaClass: HolothuroideaPhylum: ChordataSubphylum: UrochordataSubphylum: CephalochordataPhylum: MolluscaClass: Cephalopoda•Octopus, squid, cuttlefish, nautilus•Most complex of all invertebrates•Well-developed eyes, nervous system, sense organs•Reduction or loss of external shell(can be internal remnant)•Mantle thick and muscular•Locomotion by forcing water•Sucker-lined tentacles developed from foot (8; or 8+2; or many)Moves by forcing water through the mantle cavity and foot modified into funnel. Mostly an escape mechanism, normally swim using fins or crawl using tentaclesoctopuscuttlefishsquidM. Vecchione et al., Science 294, 2505 (2001) Fig. 1. Video frames of bathypelagic squids observed from submersibles. 2000-4700 m deep! Severalseen in theGulf of MexicoDeep-seasquid discoveredby videoThe Worm Problem“Worminess” is a very useful property in the marine environment•movement through sediment, nooks and crannies•Hydrodynamics (minimizing drag)•“reach” for predators (think of snakes)•Simple plumbing (hydrostatic skeleton)Ergo, convergent evolution: there are lots of animals across many phyla for which the first impression is “worms”For the marine biologist the problem is telling them apart!!!Kingdom: AnimaliaPhylum: PoriferaPhylum: CnidariaClass: HydrozoaClass: ScyphozoaClass: AnthozoaPhylum: CtenophoraPhylum: PlatyhelminthesPhylum: NemertinaPhylum: GastrotrichaPhylum: KinorhynchaPhylum: PriapulidaPhylum: NematodaPhylum: EntoproctaPhylum: EctoproctaPhylum: CycliophoraPhylum: PhoronidaPhylum: BrachiopodaPhylum: MolluscaClass: AplacophoraClass: MonoplacophoraClass: PolyplacophoraClass: GastropodaClass: ScaphopodaClass: BivalviaClass: CephalopodaPhylum: SpinuculaPhylum: EchiuridaPhylum: PogonophoraPhylum: HemichordataPhylum: ChaetognathaPhylum: AnnelidaPhylum: ArthropodaSubphylum: ChelicerataClass: MerostomataClass: PycnogonidaSubphylum: CrustaceaClass: BranchiopodaClass: OstracodaClass: CopepodaClass: CirripediaClass: MalacostracaPhylum: EchinodermataClass: AsteriodeaClass: OphiuroideaClass: EchinoideaClass: CrinoideaClass: HolothuroideaPhylum: ChordataSubphylum: UrochordataSubphylum: Cephalochordatawww.georgiafaces.caes.uga.edu/www.downbelow.co.uksplashingtime.comwww.islandream.comPlatyhelminth wormswww.carolscornwall.comEchiuroid wormwww.seaslugforum.netSmithsonian Tropical Research InstituteNemertean wormshttp://www.glaucus.org.uk/Sipunculid wormshttp://www.marlin.ac.uk/http://globec.whoi.edu/globec-dir/reports/al9906/Image35.gifhttp://www.arcodiv.org/watercolumn.htmlChaetognatha“Arrow worms”Marlétaz and Le Parco BMC Evolutionary Biology 2008 8:251Phylogenetic analysis