Retusa truncatula

Retusa truncatula (Bruguière, 1792)

Retusa truncatula @ Croatia by Pero Ugarković




































Retusa truncatula  (Bruguière, 1792)

 Classification according to Bouchet et al. (2017)
Taxonomic source: World Register of Marine Species (AphiaID: 141138).

  • Bulla mammillata Philippi, 1836
  • Bulla pellucida Brown, 1827
  • Bulla retusa Maton & Rackett, 1807
  • Bulla semisulcata Philippi, 1836
  • Bulla truncata Adams J., 1800
  • Bulla truncatula Bruguière, 1792 (original)
  • Coleophysis effusa Monterosato, 1890
  • Cylichna mammillata Forbes & Hanley, 1850
  • Cylichna truncata Forbes & Hanley, 1850
  • Cylichna truncatella Locard, 1886
  • Retusa (Coleophysis) piriformis Nordsieck, 1972
  • Retusa carinensis de Gregorio, 1889
  • Retusa dilatata Pallary, 1904
  • Retusa dilatata var. minor Pallary, 1904
  • Retusa mamillata Pruvot-Fol, 1954
  • Retusa piriformis Nordsieck, 1972
  • Retusa retusa Winckworth, 1932
  • Retusa semisulcata (Philippi, 1836)
  • Tornatina mammillata Massy, 1930
  • Tornatina truncatula Massy, 1930
  • Utriculus mammillatus Jeffreys, 1867
  • Utriculus truncatulus Jeffreys, 1867

The base colour of the body is white, and has a head shield indented anteriorly that forms two lobes directed backwards with no middle line. There are two pointed cephalic tentacles. There are no lateral extensions of the foot (parapodial lobes) nor an extension of the mantle under the snail (pallial lobe). Internal organs are not visible trough the shell. The eyes are visible. It has no radula. The foot is elongate, with rounded corners and indented anteriorly. The shell is small (up to 5mm), glossy, coloured white, translucent white or yellowish, with longitudinal striations. It is relatively thick, external, and usually with an elongate cylindrical shape. The opening is narrow, but extends for the length of the shell, and usually beyond its top. The top of the shell (apex) is sunken; in some specimens the apex may be truncated (shortened) or slightly extended out of the shell (mamillate). The shells are mostly umbilicated and have a pattern of prominent growth lines; however spiral grooves can be found in mamillate specimens. It has no operculum.

It lives buried in sand, muddy sand and on gravel from the intertidal zone down to depths of 300 m (Thompson, 1988; Høisæter, 2009). It feeds on small molluscs like Peringia ulvae, perhaps also on foraminiferans and small lamellibranchs.


  • Retusa. From Latin “retusus”, blunt.
  • Truncatula. From Latin, means truncated.

Quite common in the European fossile record, living specimens occur along the entire Norwegian coast, the British Isles, France and Spain Atlantic shores and to the Canary Islands, Madeira and Azores. Present across the Mediterranean Sea (Thompson, 1988; Brattegard & Holthe, 2001; Høisæter 2009) and the Black Sea. In Spain it is present in all the coasts, both Atlantic and Mediterranean. In Catalonia it is present in the fossile record at Ciurana, and living specimens have been found at Tossa de Mar, at Garraf and in the coasts of Tarragona. Because of its small size and living habits (it lives buried in sand) it has been commonly overlooked.

Known georeferenced records of the species: Retusa truncatula
: GROC 2010-2011
: Enric Madrenas
: João Pedro Silva
: Bernard Picton
: Manuel Ballesteros.
: M@re Nostrum
: Altres fonts
: Marine Regions


    Western Mediterranean: ★★☆☆☆
    Eastern Mediterranean: ★★☆☆☆
    Atlantic Ocean: ★★☆☆☆

This chart displays the monthly observation probability for Retusa truncatula based on our own records.

More pictures


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Further reading

Cite this article as:

Ballesteros, M., Madrenas, E. & Pontes, M. (2023) "Retusa truncatula" in OPK-Opistobranquis. Published: 10/09/2014. Accessed: 02/12/2023. Available at (

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