Polychaete
Diverse marine annelids with bristle-bearing parapodia.
Last updated
Cosmic73 · CC BY-SA 4.0
The known species of polychaetes share only a few characteristics.[1] Commonly referred to as bristle worms or polychaetes, Polychaeta is a paraphyletic class consisting mainly of marine annelid worms.[2] These annelids are segmented, with most individuals measuring under 10 cm, though the species Eunice aphroditois can span from 1 mm to 3 m in length.[3]
Quick Facts
- Field
- Marine biology, annelid taxonomy
- Species described
- More than 10,000
- Size range
- 1 mm (0.039 in) to 3 m (Eunice aphroditois)
- Habitat
- All world oceans, all depths; a few freshwater and semiterrestrial species
Facts from the source article.
Key facts and history
For locomotion and, frequently, as the main respiratory organs, each body segment is equipped with a set of paddle-shaped, heavily vascularized parapodia.[3] Protruding from the parapodia are clusters of bristles known as chaetae.[3] In comparison to other annelids, the prostomium (head) is more prominently developed.[4] Because polychaetes occupy roles as predators, herbivores, filter feeders, scavengers, and parasites, their mouthparts are shaped differently according to what they eat.[4]
A circulatory system that is both simple and well-developed is typically found in these worms.[3] Situated in the top portion of the head, the brain of a polychaete is notably larger than that found in other annelids.[3] Bioluminescence is a trait found in many polychaete species, with luminous members occurring across eight different families.[5] The majority of polychaetes either burrow into sediment or construct tubes there, while a number of species live as commensals.[6]
What the cited sources add
Polychaetes have survived five mass extinctions.[1] One of the world's most heat-resistant animals is a deep-sea polychaete.[1] One polychaete species can survive without oxygen for 96 hours.[1] Polychaetes are the largest group in the phylum Annelida.[7]
The free-moving polychaetes have muscular flaps called parapodia on their sides, and the setae on these dig into the sand for locomotion.[7] Some polychaete worm eyes can even detect shapes.[7]
References
- "14 Fun Facts About Marine Bristle Worms". facts only, no text reused. smithsonianmag.com
- Wikipedia, "Polychaete" (CC BY-SA 4.0), which cites: Struck, "Phylogenomic analyses unravel annelid evolution", Nature, 2011, p. 95–98 (original not read by us) en.wikipedia.org
- Wikipedia, "Polychaete" (CC BY-SA 4.0), which cites: Barnes, Robert D., "Invertebrate Zoology", Holt-Saunders International, 1982, p. 469–525 (we also read that source) en.wikipedia.org
- Wikipedia, "Polychaete" (CC BY-SA 4.0), which cites: Rodrigo, A. P., Martins, C., Costa, M. H., Alves de Matos, A. P., & Costa, P. M. (2018). A morphoanatomical approach to the adaptive features of the epidermis a; Briggs, "Decay and preservation of polychaetes: taphonomic thresholds in soft-bodied organisms", Paleobiology, 8 February 2016, p. 107–135 (original not read by us) en.wikipedia.org
- Wikipedia, "Polychaete" (CC BY-SA 4.0), which cites: Kanie, "Violet bioluminescent Polycirrus sp. (Annelida: Terebelliformia) discovered in the shallow coastal waters of the Noto Peninsula in Japan", Scientific Reports, 2021-09-27, p. 19097; Zörner, "The spatial pattern of bioluminescent flashes in the polychaete Eusyllis blomstrandi (Annelida)", Helgoland Marine Research, 22 Dec 2006, p. 55–66 (original not read by us) en.wikipedia.org
- Wikipedia, "Polychaete" (CC BY-SA 4.0), which cites: Martin, "Proceraea exoryxae sp. nov. (Annelida, Syllidae, Autolytinae), the first known polychaete miner tunneling into the tunic of an ascidian", PeerJ, 2017-06-01; Martin, "Oceanography and Marine Biology: An Annual Review", CRC Press, 1998, p. 225–254; Glasby, "Global diversity of polychaetes (Polychaeta: Annelida) in freshwater", Hydrobiologia, 2008, p. 107–115; Glasby, "The Namanereidinae (Polychaeta: Nereididae). Part 1, Taxonomy and Phylogeny", Records of the Australian Museum, Supplement 25, 1999; Annelids in Extreme Aquatic Environm en.wikipedia.org
- "Worms: Phyla Platyhelmintes, Nematoda, and Annelida", manoa.hawaii.edu. facts only, no text reused. manoa.hawaii.edu
Each numbered sentence above was checked against the source it cites before publication. Sentences citing Wikipedia adapt text from the English Wikipedia article Polychaete (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 Worms And Worm-Like Invertebrates
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.
- Wikipedia: Polychaete (CC BY-SA 4.0).
- Word definitions: the , each quoted from its Wikipedia article.
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