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Cnidaria (Coelenterates)

  1. Stanley Shostak

Published Online: 23 SEP 2005

DOI: 10.1038/npg.els.0004117



How to Cite

Shostak, S. 2005. Cnidaria (Coelenterates). eLS. .

Author Information

  1. University of Pittsburgh, Pennsylvania, USA

Publication History

  1. Published Online: 23 SEP 2005


Cnidaria (Gr., cnidae, nettle) is a phylum of mostly marine Metazoa distinguished by cnidocysts, subcellular capsules containing an inverted tubule capable of everting and, in some cases, discharging venom. Sexual reproduction results in solid planula embryos that develop into columnar polyps. Asexual reproduction results in clones of polyps, polypoidal colonies or disk- to bell-shaped sexual medusas (jellyfish).


  • cnidocyst;
  • corals;
  • Hydra;
  • jellyfish;
  • sea anemone