Starfish Codexery

Asteroidea

Last updated

Asteroidea

stephen davis · CC BY 2.0

Asteroidea, commonly known as sea stars, are secondarily radially symmetric deuterostomes whose ancestors were bilaterally symmetric.[1] They are the best known echinoderms.[1] A central disc in most starfish gives rise to five radiating arms, though the arm count differs among taxonomic groups.[2]

Scientific classification

  1. KingdomAnimalia
  2. PhylumEchinodermata
  3. ClassAsteroidea

Named by Blainville, 1830

Sources: Wikipedia taxobox: Starfish (CC BY-SA 4.0)

Quick Facts

Diversity
1,900+ species

Facts from the source article.

Biology and range

The water vascular system is a hydraulic system concerned with locomotion, adhesion, food manipulation and gas exchange.[3] The gut of a starfish fills most of the central disc and extends into the arms.[4] Most species are generalist predators, eating microalgae, sponges, bivalves, snails and other small animals.[5] Starfish inhabit marine environments globally, from tropical to polar regions.[6]

Asteroidea bunch
Asteroidea bunch. Image: stephen davis · CC BY 2.0 · Wikimedia Commons

These organisms are predominantly benthic, occupying substrates such as sand, mud, and rock.[6] The body wall is composed of several layers: an outer thin cuticle, a single-cell-thick epidermis, a thick dermis of connective tissue, a thin coelomic myoepithelial muscle layer, and an inner peritoneum lining the body cavity.[7] The madreporite, a sieve-like ossicle located on the aboral surface, serves as the entry point for water into the vascular system.[3] Different starfish species exhibit considerable variation in their lifespans.[8]

What the specialist sources record

The WoRMS database records Asteroidea as an accepted class in the marine environment.[9] GBIF holds 4,593,102 occurrence records for this taxon as of 7 October 2026.[10] According to the Invertebrate Anatomy OnLine account, asteroids are the most familiar echinoderms.[1]

References

  1. Fox, Richard, "Asterias forbesi", Invertebrate Anatomy OnLine, 2007-05-25. facts only, no text reused. lanwebs.lander.edu
  2. Wikipedia, "Starfish" (CC BY-SA 4.0), which cites: Wu, "The advantages of the pentameral symmetry of the starfish", 2012; Prager, Ellen, "Sex, Drugs, and Sea Slime: The Oceans' Oddest Creatures and Why They Matter", University of Chicago Press, 2011, p. 74; Lacalli, "A radical evolutionary makeover gave echinoderms their unusual body plan", Nature, 2023, p. 485–486 (we also read that source) en.wikipedia.org
  3. Wikipedia, "Starfish" (CC BY-SA 4.0), which cites: Ruppert et al., 2004. pp. 879–883, 889 (original not read by us) en.wikipedia.org
  4. Wikipedia, "Starfish" (CC BY-SA 4.0), which cites: Ruppert et al., 2004. p. 885 (original not read by us) en.wikipedia.org
  5. Wikipedia, "Starfish" (CC BY-SA 4.0), which cites: Carefoot, Tom, "Adult feeding", Sea Stars: Feeding, growth, & regeneration; Pearse, "Starfish: Biology and Ecology of the Asteroidea", 2014, p. 124–25; "Predator crown-of-thorns starfish (Acanthaster planci) outbreak, mass mortality of corals, and cascading effects on reef fish and benthic communities", PLOS ONE, 2012; Pearse, "Starfish: Biology and Ecology of the Asteroidea", 2014, p. 124–25; Turner, "Starfish: Biology and Ecology of the Asteroidea", 2014, p. 206–207, 210 (original not read by us) en.wikipedia.org
  6. Wikipedia, "Starfish" (CC BY-SA 4.0), which cites: Ruppert et al., 2004. pp. 876–880; Turner, "Starfish: Biology and Ecology of the Asteroidea", 2014, p. 206–207, 210; McClintock, "Population structure and energetics of the shallow-water antarctic sea star Odontaster validus in contrasting habitats", Marine Biology, 1988, p. 235–246; Ruppert et al., 2004. pp. 876–880; Dorit, "Zoology", Saunders College Publishing, 1991, p. 778–782; Turner, "Starfish: Biology and Ecology of the Asteroidea", 2014, p. 206–207, 210; "Phylogenetic revision of the Hippasterinae (Goniasteridae; Asteroidea): systemati en.wikipedia.org
  7. Wikipedia, "Starfish" (CC BY-SA 4.0), which cites: Ruppert et al., 2004. pp. 876–880; Sweat, L. H., "Glossary of terms: Phylum Echinodermata", Smithsonian Institution, 2012-10-31 (original not read by us) en.wikipedia.org
  8. Wikipedia, "Starfish" (CC BY-SA 4.0), which cites: Ruppert et al, 2004. pp. 887–889 (original not read by us) en.wikipedia.org
  9. World Register of Marine Species, Asteroidea (AphiaID 123080). CC BY 4.0. marinespecies.org
  10. GBIF Backbone Taxonomy and occurrence index, Asteroidea (taxon key 214). CC BY 4.0 (backbone); counts are facts. gbif.org

Each numbered sentence above was checked against the source it cites before publication. Sentences citing Wikipedia adapt text from the English Wikipedia article Starfish (contributors), used under CC BY-SA 4.0; this entry is available under the same licence. Other sources were used for facts only; no text or images are copied from them.

More in Starfish

Starfish regenerationSea star wasting diseaseAlloceramasterAquilonastraAsteriasAstrometisAstropectenChoriasterCulcita (echinoderm)EchinasterHenriciaLeptasterias

Sources

Compiled from Wikipedia and the sources listed below. Text from Wikipedia is available under CC BY-SA 4.0; this entry is adapted from it.

Spotted an error? Know more?

Reader corrections go straight into our review queue. Suggest an edit · How this site is sourced

Comments

Loading…
Open in the interactive codex →