Marine invertebrates

Marine invertebrates are animals that inhabit a marine environment and are invertebrates, lacking a vertebral column. In order to protect themselves, they may have evolved a shell or a hard exoskeleton, but this is not always the case.

As on land and in the air, invertebrates make up a great majority of all macroscopic life in the sea. Invertebrate sea life includes the following phyla:

Acoela;
Annelida, (polychaetes and sea leeches);
Brachiopoda;
Bryozoa, also known as moss animals or sea mats;
Chaetognatha;
Cephalochordata;
Cnidaria, such as jellyfish, sea anemones, and corals;
Crustacea, including lobsters, crabs, shrimp, crayfish, barnacles, hermit crabs, mantis shrimps, and copepods;
Ctenophora, also known as comb jellies;
Echinodermata, including sea stars, brittle stars, sea urchins, sand dollars, sea cucumbers, crinoids, and sea daisies;
Echiura;
Gnathostomulids;
Gastrotricha;
Hemichordata;
Kamptozoa;
Kinorhyncha;
Loricifera;
Merostomata; also know known as horseshoe crabs;
Mollusca, including shellfish, squid, octopus, whelks, Nautilus, cuttlefish, nudibranchs, scallops, sea snails, Aplacophora, Caudofoveata, Monoplacophora, Polyplacophora, and Scaphopoda;
Myzostomida;
Nemertinea (ribbon worms);
Orthonectida;
Phoronida;
Placozoa;
Porifera (sponges);
Priapulida;
Pycnogonida (sea spiders);
Sipunculida;
Tunicata, also known as sea squirts;
Some flatworms of the classes Turbellaria and Monogenea;
Xenoturbella;
Xiphosura.

References

List of Animal Phyla

Aquatic ecosystems – general and freshwater components

General	Aquatic ecosystems Acoustic ecology Agent-based models Algal bloom Anoxic waters Aquatic adaptation Aquatic animals Aquatic biodiversity research Aquatic biomonitoring Aquatic insects Aquatic layers Aquatic mammals Aquatic plants Aquatic predation Aquatic respiration Aquatic science Aquatic toxicology Benthos Bioluminescence Biomass Cascade effect Colored dissolved organic matter Dead zone Ecohydrology Eutrophication Fisheries science Food chain Food web GIS and aquatic science Hydrobiology Hypoxia Isotope analysis Microbial ecology Microbial food web Microbial loop Nekton Neuston Particle Photic zone Phytoplankton Plankton Productivity Ramsar Convention Schooling Sediment trap Siltation Spawning Substrate Thermal pollution Trophic level Underwater camouflage and mimicry Water column Zooplankton More...

Freshwater	Freshwater ecosystems Brackish marsh Freshwater biology Freshwater biomes Freshwater fish Freshwater marsh Freshwater swamp forest Hyporheic zone Lake ecosystems Landscape limnology Limnology Lake stratification Macrophyte Pond Fish pond Rheotaxis River ecosystems Stream bed Stream pool Trophic state index Upland and lowland Water garden Wetland Environmental quality More...

Ecoregions	Freshwater ecoregions List of freshwater ecoregions Marine ecoregions List of marine ecoregions Ecology of the Everglades Ecology of the San Francisco Estuary Ecosystem of the North Pacific Subtropical Gyre Freshwater ecology of Maharashtra

Aquatic ecosystems – marine components

Marine	Marine ecosystem f-ratio Iron fertilization Iron Hypothesis Large marine ecosystem Marine biology Marine chemistry Marine snow Ocean nourishment Oceanic physical-biological process Ocean turbidity Photophore Thorson's rule Upwelling Whale fall More...

Marine life forms	Census of Marine Life Coastal fish Coral reef fish Deep sea communities Deep sea creature Deep sea fish Deep water corals Demersal fish Marine bacteriophage Marine invertebrates Marine larval ecology Marine mammal Marine reptile Marine vertebrate Paradox of the plankton Pelagic fish Seabird Seashore wildlife Wild fisheries

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Issues	Ecological values of mangrove Fisheries and climate change HERMIONE Marine conservation Marine conservation activism Marine pollution Marine Protected Area

Marine invertebrates

See also

References