Facelina annulicornis

Facelina annulicornis (Chamisso & Heysenhardt, 1821)

Facelina annulicornis @ Costa Brava (Spain) by Enric Madrenas

WoRMS Taxonomic Information

Current accepted name: Facelina annulicornis (Chamisso & Eysenhardt, 1821)

Current classification

SuperdomainBiota
KingdomAnimalia
PhylumMollusca
ClassGastropoda
SubclassHeterobranchia
InfraclassEuthyneura
SubterclassRingipleura
SuperorderNudipleura
OrderNudibranchia
SuborderCladobranchia
SuperfamilyAeolidioidea
FamilyFacelinidae
GenusFacelina
SpeciesFacelina annulicornis (Chamisso & Eysenhardt, 1821)
Synonyms

  • Eolidia annulicornis Chamisso & Eysenhardt, 1821
  • Eolis punctata Alder & Hancock, 1845
  • Facelina punctata (Alder & Hancock, 1845)

Description
This facelinid can reach a size of more than 30 mm in length. The body is translucent white with the back tinted pink and the head tinted cream. The oral tentacles are approximately twice as long as the rhinophores, and also colored translucent white, with opaque white dots on basal half. The cephalic region and the back of the animal, as well as the surface of the cerata is sprayed with small white circular spots. In front of the base of the rhinophores a dark brown stain can be seen with the form of a mask, while another curved similar stain goes back, crossing between the rhinophores and directed to the left. These stains correspond to the pigmentation of the buccal bulb and esophagus. The rhinophores are translucent, with a brown ring near the light yellow apex and fine lamellae slightly oblique along its full surface. The eyes are located behind the base of the rhinophores. The cerata are grouped in 6-7 series on each side of the body, with the first group well separated from others by a space corresponding to the cardiac region. Numerous cerata in the first and second group are distributed in 3 rows, while in the remaining groups, cerata are distributed in two rows. The cerata are elongated and slightly curved, progressively decreasing in thickness from the base to the apex. The digestive gland within the cerata is dark brown and occupies all the cerata but the apex, which is transparent; cerata are sprayed white, as the rest of the body. The foot is transparent and under the head evolves to two well-developed propodial palps, translucent white with opaque white dots on its front side.

Biology
F. annulicornis is a very active species that is often found wandering on different substrates in search of food, usually hydrozoans of the genus Eudendrium, Obelia, Pennaria and Tubularia. It is cited that animals placed in aquariums can prey on other nudibranchs’ spawns and even adult specimens of aeolidaceans or dendronotaceans. The spawn is a cord wrapped in a somewhat irregular spiral filled with pink eggs about 80 microns in diameter.

Etymology

  • Facelina – Latin for lined face
  • annulicornis – Latin for ringed horns

Distribution
This species has been recorded in continental European shores, in the British Isles from Scotland, in the French Atlantic, in the Iberian Peninsula in its coastal areas, Canary Islands, Azores and Madeira. Also present in the Western Mediterranean and the Balearic Islands. In Catalonia it has been cited in different coastal locations of the Costa Brava such as Cala Sant Antoni and Es Caials (Cadaqués), Aiguablava (Begur), L´Escala, Tossa de Mar and Cala Sant Francesc (Blanes).

Known georeferenced records of the species: Facelina annulicornis
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
Facelina auriculata, larger, rhinophores lamellated only distally and coloured white in the front side. Cerata with blue tones. First 3 groups of cerata with 2-3 rows, the rest with only one.

Abundance

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

This chart displays the monthly observation probability for Facelina annulicornis based on our own records.

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More pictures

Bibliography

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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. (2025) "Facelina annulicornis" in OPK-Opistobranquis. Published: 17/05/2012. Accessed: 03/09/2026. Available at (https://opistobranquis.info/en/?p=627)