Home Guide to Opisthobranchs Nudibranchia Doridina Doridoidei Onchidoridoidea Okenia aspersa

Okenia aspersa

Okenia aspersa (Alder & Hancock, 1845)

Okenia aspersa @ Pointe de l'Espiguette, France by Pascal Girard

Taxonomy
 

Superdomain

Biota  

 

Kingdom

Animalia  

 

Phylum

Mollusca  

 

Class

Gastropoda  

 

Subclass

Heterobranchia  

 

Infraclass

Euthyneura  

 

Subterclass

Ringipleura  

 

Superorder

Nudipleura  

 

Order

Nudibranchia  

 

Suborder

Doridina  

 

Infraorder

Doridoidei  

 

Superfamily

Onchidoridoidea  

 

Family

Goniodorididae  

 

Subfamily

Goniodoridinae  

 

Genus

Okenia  

 

Species

Okenia aspersa  (Alder & Hancock, 1845)

 
 Classification according to Bouchet et al. (2017)
Taxonomic source: World Register of Marine Species (AphiaID: 140035).
Synonyms

  • Doris quadricornis Montagu, 1815
  • Idalia aspersa Alder & Hancock, 1845
  • Idalia caudata Orested, 1844 
  • Idalia modesta Verrill, 1875 
  • Idalia pulchella Alder & Hancock, 1854
  • Idaliella modesta (A. E. Verrill, 1875)
  • Okenia ascidicola M. P. Morse, 1972 
  • Okenia leachii var. quadricornis (Montagu, 1815)
  • Okenia modesta (A. E. Verrill, 1875) 
  • Okenia pulchella (Alder & Hancock, 1854)
  • Okenia quadricornis (Montagu, 1815)

Description
With a lenght of about 15-20 mm, the reddish brown body bears spicules and a narrow pallial ridge with 16 simple appendages, of which the anterior 4 are elongate, while the remainder are shorter, all of the same colour of the body. Small areas of the flanks, veil, tail, rhinophores, gills and appendages show a darker colour and there are yellow patches scattered everywhere but the ventral surface of the foot. Also there are opaque white spots scattered over flanks, veil and tail, that shows a white middle line from the gills to almost its tip. The frontal velum is slightly bilobed. The rhinophores, having 43 lamellae, are a little longer than the anterior appendages, all of them with hyaline white tips. The branchial tuft has 11 unipinnate gills. The spicules lie within the integument and up to the tips of the pallial ridge appendages. The genital pore opens on the right of the anterior third of the animal’s body.

Biology
Okenia aspersa is reported to feed on Ascidiella spp. (Thompson, 1964; Thompson & Brown, 1976; Todd, 1981) and Molgula spp. (Holt, 1891; Thompson & Brown, 1976; Just & Edmunds, 1985; Picton & Morrow, 1994; Valdés & Ortea, 1995).

Etymology

  • Okenia. In honor of Prof. Dr. Ludwig Gilbert Lorenz Oken, (1779-1851), German natural philosopher, editor of the magazine “Isis” and publisher of the book “Lehrbuch der Naturgeschichte”.
  • Aspersa. From Latin “aspersus”, sprinkled, powdered.

Distribution
This species has been reported from Norway to Southern Portugal, also in the Western Mediterranean where it has been found in France, Italy and Malta. A report of Okenia ascidicola from Massachussetts, USA (Morse, 1972), that is now considered a synonim of O.aspersa, should be verified molecularly.

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

Abundance

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

This chart displays the monthly observation probability for Okenia aspersa based on our own records.

Videos

 

More pictures

Okenia aspersa Two spawn coils. Location Bushmills Bay, Causeway Coast, coordinates 55.230417,-6.5528, depth 27.5m, date 08-06-2010. – Photograph ©Bernard Picton
Okenia aspersa disruptive camouflage. Location White Cliffs, Rathlin, Rathlin Island, coordinates 55.292767,-6.240267, depth 30m, date 14-06-2007. – Photograph ©Bernard Picton
Okenia aspersa @ Tiree, W. Scotland. Collected Bob Earll, photo by Bernard Picton
Okenia aspersa @ Penzance, UK 20200509 by David Fenwick
Okenia aspersa by Cervera el al (1991)
Okenia aspersa @ France by Pascal Girard

Bibliography

    Alder J, Hancock A. 1845. A monograph of the British nudibranchiate Mollusca: with figures of all the species. Ray Society, London.
    Ballesteros M, Madrenas E, Pontes M. 2025. OPK - Opistobranquis. Available from https://opistobranquis.info/.
    Behrens DW. 2004. Pacific Coast nudibranchs, Supplement II. New species to the Pacific Coast and new information on the oldies. Proceedings of the California Academy of Sciences (4) 55(2): 11–54.
    Betti F, Cattaneo-Vietti R, Bava S. 2015. First records from the Ligurian Sea of the cold water species Okenia aspersa and Doto koenneckeri (Gastropoda: Nudibranchia). Marine Biodiversity Records 8, e2015. https://doi.org/10.1017/S1755267215000846.
    Cervera JL, López-González PJ, García-Gómez JC. 1991. Taxonomic and geographical range data on two rare species of Okenia (Gastropoda: Nudibranchia: Doridacea) from the Eastern Atlantic. The Veliger 34 (1): 56-66.
    Cervera JL, Calado G, Gavaia C, et al. 2004. An annotated and updated checklist of the opisthobranchs (Mollusca: Gastropoda) from Spain and Portugal (including islands and archipelagos). Boletín Instituto Español de Oceanografía, 20 (1-4): 1-111. L.
    Debelius H, Kuiter RH. 2007. Nudibranchs of the world. Frankfurt: IKAN- Unterwasserarchiv. 360 pp. p.
    Edmunds M. 1968. Acid secretion in some species of Doridacea (Mollusca, Nudibranchia). Proceedings of the Malacological Society of London 38:121-133; tbls. 1-3; figs. 1-4.
    Garcia FJ, Bertsch H. 2009. Diversity and distribution of the Gastropoda Opisthobranchia from the Atlantic Ocean: A global biogeographic approach. Scientia Marina. 73(1):153–160. https://doi.org/10.3989/scimar.2009.73n1153.
    García-Gómez JC, Cervera JL, García FJ, et al. 1991. Resultados de la campaña internacional de biología marina “Algarve 88”: moluscos opistobranquios. Bollettino Malacologico 27 (5-9): 125-138.
    Høisæter T. 1986. An annotated check-list of marine molluscs of the Norwegian coast and adjacent waters. Sarsia 71(2):73-175.
    Just H, Edmuns M. 1985. North atlantic nudibranchs (Mollusca) seen by Henning Lemche. Ophelia supplement 2: 1-150.
    Long SJ. 2006. Bibliography of Opisthobranchia 1554-2000. Bayside Books & Press, Tustin, CA, U.S.A. 672p.
    McDonald G. 2009. Bibliographia Nudibranchia. 2nd Online Edition, Annotated. 1072 pp  Institute of Marine Sciences, University of California, Santa Cruz. Available from http://escholarship.org/uc/item/8115h0wz.
    McKay DW, Smith SM. 1979. Marine Mollusca of east Scotland. Royal  Scottish Museum. 185 pp. p.
    McMillan NF. 1968. British shells, xii + 196 pp. Frederick Warne & Co., Ltd.
    Picton B. 1981. Collections of nudibranch Mollusca from the Republic of Ireland made during 1981. Report to the Praeger Committee, Royal Irish Academy, Dublin, 5 unnumbered pp.
    Picton BE, Morrow C. 1994. Okenia aspersa accessed through: Nudibranchs of the British Isles on 2014-12-14. Available from http://www.habitas.org.uk/marinelife/species.asp?item=W13010#.
    Picton BE, Morrow C. 1994. A Field guide to the Nudibranchs of the British Isles. London: Immel Publishing Ltd. London: 143 pp.
    Pola M, Paz-Sedano S, Macali A, et al. 2019. What is really out there? Review of the genus Okenia Menke, 1830 (Nudibranchia: Goniodorididae) in the Mediterranean Sea with description of two new species. PLoS ONE 14(5): e0215037. https://doi.org/https://doi.org/10.1371/journal.pone.0215037.
    Pruvot-Fol A. 1954. Mollusques opisthobranches. Paris, France: Paul Lechevalier (Faune de France). 460 p.
    Rudman WB. 2007. Two new species of Okenia (Nudibranchia: Goniodorididae) from eastern Australia and Tanzania. Zootaxa 1657 : 57-67.
    Rudman WB. 2004. Further species of the opisthobranch genus Okenia (Nudibranchia: Goniodorididae) from the Indo-West Pacific. Zootaxa 695 : 1-70.
    Seaward DR. 1982. Sea area atlas of the marine molluscs of Britain and Ireland. Conchological Society of Great Britain & Ireland / Nature Conservancy Council, 242 pp.
    Thiele J. 1931. Handbuch der systematischen Weichtierkunde 1. Jena (Fischer): i-vi, 1-778, 783 figs.
    Thiele J, Bieler R, Mikkelsen PM. 1992. Handbook of systematic malacology. Washington, D.C.: Smithsonian Institution Libraries : National Science Foundation.
    Thollesson M. 1999. Phylogenetic analysis of dorid nudibranchs (Gastropoda: Doridacea) using the mitochondrial 16S rRNA gene. Journal of Molluscan Studies 65(3):335-353.
    Thollesson M. 2000. Increasing fidelity in parsimony analysis of dorid nudibranchs by differential weighting, or a tale of two genes. Molecular Phylogenetics and Evolution August, 2000. 16 (2): 161-172.
    Thompson TE. 1964. Grazing and the life cycles of British nudibranchs, pp 275-297, In: D. J. Crisp (ed ), Grazing in terrestrial and marine environments. British Ecological Society Symposium No. 4, 322 pp Blackwell, Oxford.
    Thompson TE. 1988. Molluscs: benthic opisthobranchs (Mollusca: Gastropoda) keys and notes for the  identification of the species. 2nd ed. Avon, Great Britain: Brill, E. J. & Backhuys, W. (Synopses of the British fauna,). 356 p.
    Thompson TE, Brown GH. 1984. Biology of Opisthobranch Molluscs. Vol. 2. Ray Society, London 156, pp. 229:
    Thompson TE, Brown GH. 1976. British opisthobranch molluscs Mollusca: Gastropoda; keys and notes for the identification of the species. London: Acad. Pr. (Synopses of the British fauna). 203 S. p.
    Todd CD. 1981. The ecology of nudibranch molluscs. Oceanography & Marine Biology Annual Review 19:141-234.
    Trainito E, Doneddu M. 2014. Nudibranchi del Mediterraneo. 2nd. Il Castello. 192 p.
    Turk SM, Seaward DR. 1997. The marine fauna and flora of the Isles of Scilly - Mollusca. Journal  of Natural History 31(4):555-633.
    Urgorri V, Diaz-Agras G, Besteiro C, et al. 2011. Additions to the inventory of Mollusca Opisthobranchia of Galicia (NW Iberian Peninsula). Thalassas. 27(2):77–100. Available from ://WOS:000291629300006.
    Valdés Á, Ortea J. 1995. Revised taxonomy of some species of the genus Okenia Menke, 1830 (Mollusca: Nudibranchia) from the Atlantic Ocean, with the description of a new species. The Veliger, 38(3): 223-234.
    Wägele H, Vonnemann V, Wägele W. 2003. Toward a phylogeny of the Opisthobranchia. Molecular Systematics and Phylogeography of Mollusks.:185–228. Available from ://CCC:000221520800008.
    Winckworth R. 1932. The British marine Mollusca. Journal of Conchology 19(7):211-252.
    WoRMS Editorial Board. 2025. World Register of Marine Species. WoRMS. Available from http://www.marinespecies.org.

    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. (2012-2025) "Okenia aspersa" in OPK-Opistobranquis. Published: 19/10/2014. Accessed: 03/02/2025. Available at (https://opistobranquis.info/en/?p=16277)