Palio nothus

Palio nothus (Johnston, 1838)

Palio nothus @ Loch Sween, Scotland 20160206 by Matt Barnes
















































Palio nothus  (G. Johnston, 1838)

 Classification according to Bouchet et al. (2017)
Taxonomic source: World Register of Marine Species (AphiaID: 182808).

  • Polycera nothus (Johnston, 1838)
  • Polycera ocellata Alder & Hancock, 1842 
  • Triopa nothus Johnston, 1838 (original)

Length up to 28 mm. The body is tall and with the animal in extension, it is somewhat narrower in the middle area between the rhinophores and the gill. Very dark brown body, sometimes in olive tones, except whitish spots throughout the body that correspond to conical tubercles of different sizes. The margins of the dorsum are very well marked around the whole animal and are also whitish and tuberculate. The rhinophores and gills are brown. On both sides of the gill there are white rounded papillae. Rhinophors with lighter coloured leaves. The foot is whitish.

It lives from the intertidal zone down to 20-30 m in rocky areas with the bryozoans it feeds on. The spawn is a spirally wound ribbon of a turn and a half with white eggs.


  • Nothus. From Latin “nothus”, cross-bred, mixed, mongrel, false, spurious, illegitimate (known father).

Basically an Atlantic species, Palio nothus has very few citations in the Mediterranean. The first cite for the Mediterranean corresponds to (Alen Petani, 2011) on the island of Vir, Croatia. Enric Madrenas’ finding in the Cap de Creus in 2015 we believe is the first report for the Western Mediterranean.

Known georeferenced records of the species: Palio nothus
: 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 Palio nothus based on our own records.

More pictures


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    Ballesteros, M., E. Madrenas, and M. Pontes. 2023. OPK - Opistobranquis. (
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    Bibliography based on the works by Steve Long, 2006. Bibliography of Opisthobranchia 1554-2000 and Gary McDonald, 2009. Bibliographia Nudibranchia, with later updates from other resources.

Further reading

Cite this article as:

Ballesteros, M., Madrenas, E. & Pontes, M. (2023) "Palio nothus" in OPK-Opistobranquis. Published: 20/10/2014. Accessed: 28/02/2024. Available at (

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