Fiona pinnata

Fiona pinnata (Eschscholtz, 1831)

Fiona Pinnata 40mm @ Cala Rajada, Mallorca 25-06-2020 by David Martinez & Joan Sans

WoRMS Taxonomic Information

Current accepted name: Fiona pinnata (Eschscholtz, 1831)

Current classification

SuperdomainBiota
KingdomAnimalia
PhylumMollusca
ClassGastropoda
SubclassHeterobranchia
InfraclassEuthyneura
SubterclassRingipleura
SuperorderNudipleura
OrderNudibranchia
SuborderCladobranchia
SuperfamilyFionoidea
FamilyFionidae
GenusFiona
SpeciesFiona pinnata (Eschscholtz, 1831)
Synonyms

  • Doris fasciculata Gmelin, 1791 
  • Eolidia longicauda Quoy & Gaimard, 1832
  • Eolidia natans d’Orbigny, 1837
  • Eolidia pinnata Eschscholtz, 1831 (original)
  • Fiona atlantica Bergh, 1857 
  • Fiona marina Eliot, 1910 
  • Hymenaeolis elegantissima Costa A., 1867 
  • Limax marinus Forsskål in Niebuhr, 1775 
  • Oithona nobilis Alder & Hancock, 1851

Description
Animals of 50 mm in length have been reported, but the most common size is about 20 mm. Its color varies depending on its food from white to brown or violet blue. Oral tentacles and rhinophores are very similar and short, rhinophores are smooth. The ceratas are very numerous, without being apparently grouped and are directed sideways, each cerata has a somewhat scalloped membranous band on its inner face and lacks a cnidosac at its distal end. The margin of the foot is scalloped and lacks propodial tentacles. The anus leads to a dorsolateral anal papilla, located approximately in the center of the body. Alder & Hancock (1851) made a remarkable anatomical description of this species under the name of Oithona nobilis.

Biology
It is one of the few pelagic nudibranch species that lives on the high seas on floating objects. It feeds on cirriped crustaceans of the genus Lepas that grow on these floating objects (Wirtz, 1998, 1999). It has also been mentioned that it feeds on pelagic hydrozoans such as Velella velella (Wirtz, 1998) and Porpita porpita. If it finds adequate food, F. pinnata has a very fast growth rate, reaching a size of 20 mm in just 4-5 days.

Etymology

  • Fiona. Latinised form of the Gaelic word fionn, meaning “white”, “fair”.
  • Pinnata. From Latin “pinnātus”, feathered, pinnate, winged.

Distribution
It is a cosmopolitan species that has been reported in all the world’s oceans. The featured picture on this page corresponds to a finding by David Martínez and Joan Sans on 25/06/2020 of about 30 specimens, including adults (up to 40mm.), juveniles and egg spawns, who lived in a plastic fruit box drifting along the coast of Cala Rajada (Mallorca). In Catalonia it has been found in few locations, always associated with floating objects that reach the coast.

Known georeferenced records of the species: Fiona pinnata
Sources:
OBIS
GROC 2010-2011
Enric Madrenas
João Pedro Silva
Bernard Picton
GBIF
OPK
VIMAR
Manuel Ballesteros
M@re Nostrum
Altres fonts
Marine Regions

Similar species
Due to its morphology and way of life, it does not resemble any other nudibranch.

Abundance

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

This chart displays the monthly observation probability for Fiona pinnata based on our own records.

More pictures

Bibliography

    1246567 Fiona pinnata 1 eunomia-revista-en-cultura-de-la-legalidad 50 creator asc 1 12295 https://opistobranquis.info/wp-content/plugins/zotpress/

    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. (2025) "Fiona pinnata" in OPK-Opistobranquis. Published: 13/08/2014. Accessed: 03/09/2026. Available at (https://opistobranquis.info/en/?p=12295)