Cerberilla bernadettae

Cerberilla bernadettae (Tardy, 1965)

Cerberilla bernadettae 20mm @ Sepieres (L'Escala) in 8 m 4-08-2016 by Enric Madrenas










































Cerberilla bernadettae  J. Tardy, 1965

 Classification according to Bouchet et al. (2017)
Taxonomic source: World Register of Marine Species (AphiaID: 138719).

  • Cerberilla bernadetti Tardy, 1965

This species can reach up to 20 mm. of length. It has a translucent white body, with a relatively flat and rounded back. The foot is very wide, translucent white and dotted with small brown spots. The anterior part of the foot forms two short tentacles adorned with a white line (sometimes orange) which are usually directed backwards. On both sides of the mouth it has two very long and thin oral tentacles, translucent with an opaque dorsal side, decorated with a white line more or less marked than often has orange hue. From the base of these oral tentacles to the head there is usually a dark brown or black spot on each side. These dark spots can cover the base of the rhinophores, sometimes forming two oblique lines behind the head. The rhinophores are short and smooth, with a brown base, sometimes orange. The eyes are located in a depigmented area on the base of the rhinophores. It has many cerata covering the back of the animal. Cerata of the first three rows are shorter and less abundant than the dozen rows behind them, which gives it a “combed backwards” look. The cerata are whitish and tapered, have a yellow spot marked with a black subapical dot. Sometimes, depending on the food, it is possible to see the light brown digestive gland inside each cerata. On the back, the ceratal plume usually covers the tail, which is little or no visible at all. The anal opening is on the right side of the body, under the fifth row of cerata, while the genital apertures are also on the right side, between the second and third rows of cerata.

This species lives buried in the sand and it feeds mainly on sea anemones as Diadumene cincta, Cereus pedunculatus, Sagartia troglodytes, Actinothoe anguicoma, etc. which it prefers to attack approaching from beneath the sand to avoid contact with the stinging tentacles, despite it has also been observed directly attacking and devouring one of the tentacles not caring if the anemone contracts the tentacles to defend itself. Jean Tardy described this species “with a boldness and an incredible voracity, compared with other [Atlantic] species” noting its incredible “gluttony”. The spawn is a transparent spiral of two or three turns with about 10,000 to 20,000 eggs colored white to pink (probably the color depends on the diet of the animal) that hatch after about 5 days into a veliger larvae that will have a planktonic life before setting down to the bottom and becoming an adult.


  • Cerberilla. Probably related to Cerbère (Cervera de la Marenda in Catalan), a French commune located in the department of Pyrenees-Orientales and the Languedoc-Roussillon region near the Réserve Naturelle Cerbère-Banyuls-sur-Mer. Established in 1974, this was the first coastal marine reserve in France, covering 650 ha of sea.
  • Bernadettae. Dedicated to Bernadette, the wife of Jean Tardy, who first spotted the four specimens used for the description of the species on 27 and 28 September 1964 in Fouras (France).

Cerberilla bernadettae is very rarely seen in the wild because of its small size and its habit of burying itself in the sand. Little is known about its distribution, although it is present on the French Atlantic coast (Tardy found it off the island of Aix, Charente-Maritime, France) which has been confirmed by other local reports such as (Montaudouin et al. 2000). This species was also cited in Arcachon in 1980, in the Canary Islands (Moro et al. 1995), in Galicia and Portugal. In the Mediterranean it seems to be a much less frequent species, with an specimen observed on the French Riviera and in Corsica (DORIS, 2016), in Italy (Cattaneo-Vietti et al. 1990) and Sardinia (Cattaneo-Vietti et al. 1992) as well as on the African coast of Tunisia. Reports from South Africa (Gosliner 1985) and the Pacific: Australia (Burns, 1966 and 1974), California (McDonald, 1975), etc. should be revised by molecular studies to certify them.

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

References for the species: Cerberilla bernadettae

Similar species
Due to its characteristics, and being the only known species of the genus in the Mediterranean and near Atlantic, it is unmistakable.


    Western Mediterranean:1 out of 5 stars
    Eastern Mediterranean:0 out of 5 stars
    Atlantic Ocean:1 out of 5 stars

This chart displays the monthly observation probability for Cerberilla bernadettae based on our own records.

More pictures


Further reading

Cite this article as:

Pontes, Miquel, Manuel Ballesteros, Enric Madrenas (2022) "Cerberilla bernadettae" in OPK-Opistobranquis. Published: 13/09/2014. Accessed: 18/01/2022. Available at (https://opistobranquis.info/en/PYYJt)

To copy this cite click on the right button.