Pleurobranchus testudinarius

Pleurobranchus testudinarius (Cantraine, 1835)

Pleurobranchus testudinarius by Enric Madrenas







































Pleurobranchus testudinarius  Cantraine, 1835

 Classification according to Bouchet et al. (2017)
Taxonomic source: World Register of Marine Species (AphiaID: 140821).

  • Doris testudinaria Risso 1818
  • Pleurobranchus mammillatus Schultz in Philippi, 1836
  • Susania testudinaria Cantraine, F.J., 1840
  • Pleurobranchus denotarisi Vérany, 1846
  • Daudebardia tarentina de Stefani & Pantanelli, 1879
  • Corambe testudinaria Fischer P. 1889

This is a large species because it can reach more than 20 cm in length. The mantle is very domed and very broad, completely covering the foot. The color of the adult animal is orange-red or dark purple, but in the young speciments it is of a lighter shade. The mantle has conical protuberances that are larger in the center and whose bases are surrounded by thin purple lines. In the anterior part of the mantle there’s a slit hiding the insertion point of the rhinophores. The cephalic veil is underdeveloped. The gill is yellowish and has 18 to 30 lamellae on either side of the central shaft, its big size frequently makes it protrude from the mantle. The foot is yellowish and on its back zone there is a “pedia” gland.

Apparently it feeds on certain species of colonial tunicates although data suggest that it could be a scavenger too. Very little is known about the biology of this species. It is believed it has nocturnal habits, during the day hiding under rocks or inside caves.


  • Pleurobranchus. From Greek Pleuron, “side” + Bragchia, “gill”.
  • Testudinarius. From Latin testūdin- (root of testūdō) turtle, pertaining to or resembling a turtle or turtle shell.

Distribution predominantly Mediterranean, this species has also been recently cited for the Azores and the Canary Islands. In the Catalan coast has been observed in different locations on sandy bottoms from about 20 m depth, but also in underwater caves of the Costa Brava.

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

References for the species: Pleurobranchus testudinarius


    Western Mediterranean:2 out of 5 stars
    Eastern Mediterranean:0 out of 5 stars
    Atlantic Ocean:0 out of 5 stars

This chart displays the monthly observation probability for Pleurobranchus testudinarius based on our own records.



More pictures


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Further reading

Cite this article as:

Ballesteros, M., Madrenas, E. & Pontes, M. (2022) "Pleurobranchus testudinarius" in OPK-Opistobranquis. Published: 15/05/2012. Accessed: 07/12/2022. Available at (

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