A bristleworm (Ampharete falcata)

Distribution data supplied by the Ocean Biodiversity Information System (OBIS). To interrogate UK data visit the NBN Atlas.Map Help



A small polychaete worm up to 18 mm in length and usually yellowish or white in colour. The body is divided into two regions, a thoracic and abdominal region along with a prominent head. The anterior end is broad, short, flattened and made up of 14 segments. The posterior is thinner and made up of 12 segments. Each body segment has a lobed shaped body extension on each side called a parapod, used for locomotion. There are no bristles (chaetae) on the parapoda at the posterior end. There are projections of the body wall called branchiae separated into two groups in segments 2-5 of the anterior end. There are four branchiae in each group. The palps, a crown of tentacles from the mouth are used in feeding. There are 6-8 short, stout bristle type structures called paleae, with pointed tips on each side of the anterior end. The paleae may be covered by the branchiae. The last segment of the body has one pair of long, and a number of round, filamentous appendages.

Recorded distribution in Britain and Ireland

Recorded from Orkney, North Sea, Southampton Water, Isles of Scilly, Celtic Sea, the Irish Sea and the west coast of Scotland. Also recorded on the north east coast of Ireland.

Global distribution



Lives mainly in soft sand at depths of between 30-90 m. Can live in fragile tubes of sand or mud attached to solid objects or lying across the sea bed.

Depth range


Identifying features

  • Usually yellowish or white in colour.
  • Up to 18 mm long.
  • Body divided into two regions, a thoracic and abdominal region along with a prominent head.
  • Two simple eyespots.
  • Lobed head with tentacles that can be retracted into mouth.

Additional information

Feeds by extending its tentacles across the sediment surface. Mucus secreted by the tentacles traps food which is then carried back to the mouth. Branchiae are used for gas exchange.

Listed by

- none -


  1. Fauchald, K., 1977. The polychaete worms. Definitions and keys to the orders, families and genera. USA: Natural History Museum of Los Angeles County.

  2. Foster-Smith, J. (ed.), 2000. The marine fauna and flora of the Cullercoats District. Marine species records for the North East Coast of England. Sunderland: Penshaw Press, for the Dove Marine Laboratory, University of Newcastle upon Tyne.

  3. Hayward, P., Nelson-Smith, T. & Shields, C. 1996. Collins pocket guide. Sea shore of Britain and northern Europe. London: HarperCollins.

  4. Hayward, P.J. & Ryland, J.S. (ed.) 1995b. Handbook of the marine fauna of North-West Europe. Oxford: Oxford University Press.

  5. Holthe, T., 1986. Marine Invertebrates of Scandinavia. No. 7. Polychaeta Terebellomorpha. Norway: Norwegian University Press

  6. Howson, C.M. & Picton, B.E., 1997. The species directory of the marine fauna and flora of the British Isles and surrounding seas. Belfast: Ulster Museum. [Ulster Museum publication, no. 276.]

  7. Mackie, A.S.Y., Oliver, P.G. & Rees, E.I.S., 1995. Benthic biodiversity in the southern Irish Sea. Studies in Marine Biodiversity and Systematics from the National Museum of Wales. BIOMOR Reports, no. 1.

  8. Rouse, G.W. & Pleijel, F., 2001. Polychaetes. New York: Oxford University Press.


  1. NBN (National Biodiversity Network) Atlas. Available from: https://www.nbnatlas.org.

  2. OBIS (Ocean Biodiversity Information System),  2024. Global map of species distribution using gridded data. Available from: Ocean Biogeographic Information System. www.iobis.org. Accessed: 2024-05-20


This review can be cited as:

Heath, T.A. 2005. Ampharete falcata A bristleworm. In Tyler-Walters H. and Hiscock K. Marine Life Information Network: Biology and Sensitivity Key Information Reviews, [on-line]. Plymouth: Marine Biological Association of the United Kingdom. [cited 20-05-2024]. Available from: https://www.marlin.ac.uk/species/detail/1915

Last Updated: 13/05/2005