Trapania lineata

Trapania lineata (Haefelfinger, 1960)

Trapania lineata by Enric Madrenas

Class: Gastropoda  Cuvier, 1797
Subclass: Heterobranchia  J.E. Gray, 1840
Clade: Euthyneura  Spengel, 1881
Clade: Nudipleura  Wägele & Willan, 2000
Order: Nudibranchia  Cuvier, 1817
Suborder: Euctenidiacea  Tardy, 1970
Infraorder: Doridacea  Thiele, 1931
Superfamily: Onchidoridoidea  J.E. Gray, 1827
Family: Goniodorididae  H. Adams & A. Adams, 1854
Genus: Trapania  Pruvot-Fol, 1931
Species: Trapania lineata  Haefelfinger, 1960

This sea slug typically measures between 10 mm and 15 mm in length. The whitish body is plump in its central area, more or less dark brown in the center deppending if /what it has been eating, and decorated with iridescent white lines that run along the back, sides of the body, head, oral tentacles, rhinophores, tail and, in certain cases, also along the axis of the branchial leaves. There is a couple of pallial tentaculiform processes, directed backwards, at the sides of the rhinophores and two processes more at the sides of the gill. The oral tentacles are usually pigmented yellow-orange, as are the tips of the rhinophores and gill leaves, propodial palps, the anterior and posterior pallial fingerlike processes and the end of the tail. The rhinophores are long and wide, with the basal portion without lamellae and of the same colour of the body, and the laminar portion coloured yellow. The gill consists of three gill leaves, one in central position and two on the sides, they have a wide rachis and are tripinnate. Among the gill leaves there are usually found copepod ectoparasites. The light beige coloured anal papilla is located right behind the gill leaves. The foot is relatively narrow and of the same color of the body, in its front side there are two backwards directed finger-like propodial palps, pigmented yellow in its distal half.

This is not a common species and usually lives in dimly lit rocky walls with an abundance of algae, sponges and hydroids, also inside caves. It feeds on entoprocta (Kamptozoa) of the genus Loxosomella (Cattaneo-Vietti et al. 1990). No other details of its biology are known.


  • Trapania. Bernard Picton considers this derives from Greek Drepane meaning “sickle” or “reaping hook”, presumably referred to the appendixes located in the base of rhinophores and gills in the genus Trapania.
  • Lineata. From Latín “lineatus”, with lines, lined.

This species is, so far, endemic of the Mediterranean Sea. It has been reported on the Mediterranean coast of France, Sardinia, Turkey and from the Strait of Gibraltar in all the Iberian Mediterranean coast and the Balearic Islands (Cervera et al. 2004). In the Catalan coast it has been reported or observed in cala Es Caials, Cadaqués, L’Escala, Medes islands, Palamos, Formigues islands, Blanes, Mataró and La Pineda (Salou).

Known georeferenced records of the species: Trapania lineata
: 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 observation probability for Trapania lineata based on our own records.

More pictures


Further reading

Cite this article as:

Ballesteros, Manuel, Enric Madrenas, Miquel Pontes et al. (2012-2017) "Trapania lineata" in OPK-Opistobranquis, Published: 15/05/2012, Accessed: 18/12/2017 at (

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