Chinaman's hat (Calyptraea chinensis)

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



A limpet-like shell, up to 15 mm across and 5 mm high. Apex with small nipple-shaped beaks, often slightly coiled. Growth lines parallel to edge of aperture, sometimes, especially near the aperture, with small projections. Shell exterior white or yellow, interior pearly white. Flesh yellow with white markings. No operculum.

Recorded distribution in Britain and Ireland

Present on south-west coasts of Britain, in the western Channel and off the Isle of Man. Reaches its northern limit on the west coast of Scotland but not recorded from Ireland.

Global distribution

Extends south from the British Isles to the Mediterranean and north-west Africa.


Present on shells or under stones at low water of spring tides on sheltered shores in south-west England, and in the sublittoral on stones and shell gravel associated with soft substrata down to 20 m on the west coast of England.

Depth range


Identifying features

  • Conical shell not spirally coiled except in apical whorls (protoconch).
  • Aperture nearly circular.
  • Internal tongue-shaped partition present, extending from apex to edge of shell.
  • Flattened neck lobe present on each side of head behind tentacles.

Additional information

Calyptraea chinensis is a protandrous hermaphrodite: animals with a shell width of up to 2 mm are male, larger specimens are female. Calyptraea chinensis may spread further northwards and increase in abundance as a result of seawater warming.

Listed by

- none -


  1. Fish, J.D. & Fish, S., 1996. A student's guide to the seashore. Cambridge: Cambridge University Press.

  2. Graham, A., 1971. British Prosobranchs. London: Academic Press.[Synopses of the British Fauna, no. 2.]

  3. Graham, A., 1988. Molluscs: prosobranchs and pyramellid gastropods (2nd ed.). Leiden: E.J. Brill/Dr W. Backhuys. [Synopses of the British Fauna No. 2]

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

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

  6. Hiscock, K., Southward, A., Tittley, I., Jory, A. & Hawkins, S., 2001. The impact of climate change on subtidal and intertidal benthic species in Scotland. Scottish National Heritage Research, Survey and Monitoring Report , no. 182., Edinburgh: Scottish National Heritage

  7. 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.]

  8. McMillan, N.F., 1968. British Shells. London: Frederick Warne & Co Ltd.


  1. Centre for Environmental Data and Recording, 2018. Ulster Museum Marine Surveys of Northern Ireland Coastal Waters. Occurrence dataset accessed via on 2018-09-25.

  2. Conchological Society of Great Britain & Ireland, 2018. Mollusc (marine) data for Great Britain and Ireland - restricted access. Occurrence dataset: accessed via on 2018-09-25.

  3. Conchological Society of Great Britain & Ireland, 2018. Mollusc (marine) records for Great Britain and Ireland. Occurrence dataset: accessed via on 2018-09-25.

  4. Fenwick, 2018. Aphotomarine. Occurrence dataset Accessed via on 2018-10-01

  5. NBN (National Biodiversity Network) Atlas. Available from:

  6. OBIS (Ocean Biodiversity Information System),  2024. Global map of species distribution using gridded data. Available from: Ocean Biogeographic Information System. Accessed: 2024-07-21


This review can be cited as:

Skewes, M. 2003. Calyptraea chinensis Chinaman's hat. 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 21-07-2024]. Available from:

Last Updated: 29/08/2003