White catworm (Nephtys cirrosa)

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



Nephtys cirrosa is a thin, smooth, segmented worm, up to 10 cm in length. Its head is small, with four small antennae. Nephtys cirrosa has a large proboscis, covered in prominent papillae, that it projects and uses to dig into the sediment. It is oval in cross section but, may appear flattened (when viewed from above) owing to bristled lobes (parapods) which extend from the body. It is a lustrous white colour with golden bristled parapods. Nephtys cirrosa is an active worm which demonstrates the characteristic swimming motion (a rapid lateral wriggling, starting from the rear and increasing in amplitude towards the head) of the Nephtyidae.

Recorded distribution in Britain and Ireland

Found throughout the British Isles, where it nears the northern limit of its distribution.

Global distribution

Nephtys cirrosa reaches its northern limit in Scotland, and German Bight of the North Sea. The species is found in the Mediterranean.


Nephtys cirrosa lives infaunally in sandy sediment in the intertidal and shallow sublittoral, where it is often abundant. It does not make a definite burrow.

Depth range


Identifying features

  • Body with 90-95 segments, 6-10 cm in length and relatively thin.
  • Smooth front and back surfaces, lustrous white in colour.
  • Golden bristled parapods (locomotory structures) extend to each side giving a flattened appearance but, in section, body is oval.
  • Small head, the prostomium (a flattened sphere projecting forwards above the mouth) has four small antennae at its anterior corners.
  • Eyes are not obvious.
  • Large proboscis with many papillae (including a large mid-dorsal one) may be projected and used to dig rapidly into sediment if disturbed.
  • Chaetae (bristles) on posterior parapods very finely toothed, some sharply bent.
  • On all but the first few body segments there is a reddish, sickle-shaped gill located between the dorsal and ventral lobes of the body segment.
  • Long single tail-filament trails from the rear end.

Additional information

  • The different species of Nephtyidae are difficult to identify, requiring detailed examination of the parapoda and chaetae. Reference to Rainer (1991) is recommended.
  • Large worms are used for bait and are called 'catworms' by anglers.
  • Nephtys cirrosa prefers cleaner and coarser sand than Nephtys hombergii.
  • Four species of Nephtys (Nephtys caeca, Nephtys cirrosa, Nephtys hombergii and Nephtys longosetosa) occur intertidally in the British Isles, two others, Nephtys ciliata and Nephtys hystricis, are confined almost exclusively to the subtidal (Olive & Morgan, 1991).

Listed by

- none -


  1. Brafield, A.E., 1978. Life in sandy shores. London: Edward Arnold.

  2. Bruce, J.R., Colman, J.S. & Jones, N.S., 1963. Marine fauna of the Isle of Man. Liverpool: Liverpool University Press.

  3. Clark, R.B. & Haderlie, E.C., 1960. The distribution of Nephtys cirrosa and Nephtys hombergii of the south western coasts of England and Wales. Journal of Animal Ecology, 29, 117-147.

  4. Eleftheriou, A. & McIntyre, A.D., 1976. The intertidal fauna of sandy beaches-a survey of the Scottish coast. Scottish Fisheries Research Report, 6, 1-61.

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

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

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

  8. JNCC (Joint Nature Conservation Committee), 1999. Marine Environment Resource Mapping And Information Database (MERMAID): Marine Nature Conservation Review Survey Database. [on-line] http://www.jncc.gov.uk/mermaid

  9. Olive, P.J.W. & Morgan, P.J., 1991. The reproductive cycles of four British intertidal Nephtys species in relation to their geographical distribution (Polychaeta: Nephtyidae). Ophelia, Supplement 5, 351-361.

  10. Picton, B.E. & Costello, M.J., 1998. BioMar biotope viewer: a guide to marine habitats, fauna and flora of Britain and Ireland. [CD-ROM] Environmental Sciences Unit, Trinity College, Dublin.

  11. Rainer, S.F., 1991. The genus Nephtys (Polychaeta: Phyllodocida) of northern Europe: a review of species, including the description of N. pulchra sp. n. and a key to the Nephtyidae. Helgolander Meeresuntersuchungen, 45, 65-96.

  12. Wolff, W.J., 1971. Distribution of four species of Nephtys (Polychaeta) in the estuarine area of the rivers Rhine, Meuse and Scheldt. Vie et Milieu, Supplement 22, 677-699.


  1. Bristol Regional Environmental Records Centre, 2017. BRERC species records recorded over 15 years ago. Occurrence dataset: https://doi.org/10.15468/h1ln5p accessed via GBIF.org on 2018-09-25.

  2. Centre for Environmental Data and Recording, 2018. Ulster Museum Marine Surveys of Northern Ireland Coastal Waters. Occurrence dataset https://www.nmni.com/CEDaR/CEDaR-Centre-for-Environmental-Data-and-Recording.aspx accessed via NBNAtlas.org on 2018-09-25.

  3. Environmental Records Information Centre North East, 2018. ERIC NE Combined dataset to 2017. Occurrence dataset: http://www.ericnortheast.org.ukl accessed via NBNAtlas.org on 2018-09-38

  4. Kent Wildlife Trust, 2018. Kent Wildlife Trust Shoresearch Intertidal Survey 2004 onwards. Occurrence dataset: https://www.kentwildlifetrust.org.uk/ accessed via NBNAtlas.org on 2018-10-01.

  5. Manx Biological Recording Partnership, 2017. Isle of Man wildlife records from 01/01/2000 to 13/02/2017. Occurrence dataset: https://doi.org/10.15468/mopwow accessed via GBIF.org on 2018-10-01.

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

  7. OBIS (Ocean Biodiversity Information System),  2024. Global map of species distribution using gridded data. Available from: Ocean Biogeographic Information System. www.iobis.org. Accessed: 2024-05-25

  8. South East Wales Biodiversity Records Centre, 2018. SEWBReC Worms (South East Wales). Occurrence dataset: https://doi.org/10.15468/5vh0w8 accessed via GBIF.org on 2018-10-02.


This review can be cited as:

Budd, G.C. 2005. Nephtys cirrosa White catworm. In Tyler-Walters H. Marine Life Information Network: Biology and Sensitivity Key Information Reviews, [on-line]. Plymouth: Marine Biological Association of the United Kingdom. [cited 25-05-2024]. Available from: https://marlin.ac.uk/species/detail/1795

Last Updated: 26/10/2005