Marine Invertebrates…Part 1A few statistics…•~200,000 described species of marine animals•Many more undescribed•~2% are open ocean species (i.e. pelagic)•The rest are from shallow environments•Most described marine animals are invertebrates•Most are from two phyla: Mollusca and ArthropodaDomain, Kingdom, Phylum, Class, Order, Family, Genus, Species24= Eukarya= Animaliavery small, deep sea, or crypticintertidal, subtidal, estuariesKingdom: 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: CephalochordataBody plan symmetry links evolutionary history: Radial vs BilateralRadial: JellyfishBilateral: InsectsPhylum PoriferaMargulis and Schwartz 1988Phylum: Porifera•Sponges•Cellular-level organization•Name = “pore-bearer”Specialized cells, but no tissues or organsWater entersWater exitsInternal region Spongin fibers and…Pearse & Buchsbaum 1987Phylum: Poriferapinacocytechoanocyteamoebocyteamoebocyte secreting sponginporocytefood particles, O2•>5000 species•All are sessile…attached to rocks, pilings•Feeding restricted to small particles3 kinds of spicules, taxonomic characteristics: carbonate, silaceous, spongin (organic)NCBI: cellular organisms; Eukaryota; Fungi/Metazoa group; Choanoflagellida; CodonosigidaeChoanoflagellatesMonosiga brevicollisMorphological variation within choanoflagellatesCarr M et al. PNAS 2008;105:16641-16646©2008 by National Academy of SciencesPearse & Buchsbaum 1987Phylum: Poriferapinacocytechoanocyteamoebocyteamoebocyte secreting sponginporocyte•>5000 species•All are sessile…attached to rocks, pilings•Feeding restricted to small particlesPhylum CnidariaNybakken and McClintock 1997Phylum: Cnidaria•Tissue-level organization•Name = “nettle”•Radial symmetrypolypmedusaTentacles surrounding central mouth•Central space is digestive cavity•Two tissue layers•Two body plans“middle glue”planktonicsessileNo IntestinePearse & Buchsbaum 1987Phylum: Cnidaria•Cover tentacles and body surface•Discharge when stimulated•Cnidocil = trigger•Toxic•Adhesive•Entangling•Repellent•CarnivorousNematocyctsPearse & Buchsbaum 1987•Alternation between polyp and medusa stagesPhylum: CnidariaPhylum: CnidariaClass = Hydrozoa•Both polyp and medusa stage•Small, feathery, transparent, colonies•Siphonophores the exceptionClass = Scyphozoa (jellyfish)Class = AnthozoaLevinton 2001Phylum: CnidariaClass: HydrozoaCastro and Huber 2003Pearse & Buchsbaum 1987Phylum: CnidariaClass: HydrozoaOrder: SiphonophoraPhylum: CnidariaClass = Hydrozoa•Both polyp and medusa stage•Small, feathery, transparent, colonies•Siphonophores the exceptionClass = Scyphozoa (jellyfish)•Polyp stage reduced or absent•Up to 2 m diameter•Limited swimming ability by contracting medusa bellClass = AnthozoaScyphozoa•Feeding on plankton•Can form dense swarmsJellies feedingPhylum: CnidariaClass = Hydrozoa•Both polyp and medusa stage•Small, feathery, transparent, colonies•Siphonophores the exceptionClass = Scyphozoa (jellyfish)•Polyp stage reduced or absent•Up to 2 m diameter•Limited swimming ability by contracting medusa bellClass = Anthozoa•Medusa stage reduced or absent•Colonial (e.g. corals) or solitary (e.g. anemones)•Colonial forms secrete CaCO3or protein skeletonsAnthozoa: Corals•Feed at night•Capture zooplankton•Territory fightsPhylum CtenophoraKingdom: 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: CephalochordataNybakken and McClintock 1997Phylum: Ctenophora•Radial symmetry•Name = comb-bearers•Eight rows of ‘ctenes’•Two feeding tentacles (retract when disturbed)•Carnivorous•Few mm to 2 m in lengthrows of cilia that beat in unisonZooplankon, fish larvae, other ctenophoresBenthic CtenophorePlanktonic CtenophoresCastro and Huber 2003Phylum: Cycliophora•New phylum described in 1995!•Found on lobster mouthparts•Filter-feeders (ciliated feeding structure)•Sessile life style•Inner budding of larva (pandora larva)Dwarf malePandora larvaA single species:Symbion pandoraKingdom: 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: