Baenopsis baetica

Baenopsis baetica (García Gómez, 1984)

Baenopsis baetica @ Tarifa (Spain) by Manuel Martínez Chacón

Class: Gastropoda  Cuvier, 1797
Subclass: Heterobranchia  J.E. Gray, 1840
Clade: Euthyneura  Spengel, 1881
Clade: Nudipleura  Wägele & Willan, 2000
Order: Nudibranchia  Cuvier, 1817
Suborder: Dexiarchia  Schrödl, Wägele & Willan, 2001
Infraorder: Cladobranchia Willan & Morton, 1984
Parvorder: Aeolidida Odhner, 1934
Superfamily: Flabellinoidea  Bergh, 1889
Family: Flabellinopsidae Korshunova, Martynov, Bakken, Evertsen, Fletcher, Mudianta, Saito, Lundin, Schrödl & Picton, 2017
Genus: Baenopsis Korshunova, Martynov, Bakken, Evertsen, Fletcher, Mudianta, Saito, Lundin, Schrödl & Picton, 2017
Species: Baenopsis baetica (García-Gómez, 1984)

Taxonomic note: The classification of the Flabellinidae had remained fairly stable until in 2017 a series of works appeared (Furfaro et al., 2017; Korshunova et al., 2017) that intended to clarify the status of the Flabellinidae family. The main objective of the paper by Furfaro et al. was to molecularly characterize the Mediterranean species while the paper by Korshunova et al. wanted to delve into the phylogenetic relationships between various members of the Flabellinidae family and the other families of aeolidaceans.
Both works were based on the combination of molecular and morphological techniques and, in fact, do not offer very different results, but differ on the size and origin of the studied samples and, mainly, on the interpretation of the results. After the appearance of the paper by Furfaro et al., many Mediterranean species of the genera Calmella, Flabellina and Piseinotecus were grouped under the common genusFlabellina, but had certain problems with some species that did not fit well with the proposed classification (e.g,Flabellina babai) , discovered that the Mediterranean and Atlantic populations ofFlabellina ischitana correspond to two different cryptic species, and noted the problems of the cryptic group formed by Calmella cavolini / Flabellina confusa / Piseinotecus gaditanus, indicating the need for further studies to clarify their status.
Curiously, these studies were being carried out practically in parallel by the group of Korshunova et al. but on a much wider sample of species that included specimens from the Arctic, North Atlantic, Pacific and Indian Oceans. This second paper confirms the polyphily of the family Flabellinidae, but the interpretation of these results becomes a real revolution for the taxonomy of the aeolidaceans, especially for the family Flabellinidae.
Both papers show that there are two well differentiated clades (groups) in the Flabellinidae: species like Coryphella pedata and similars, with cerata that come directly from the back, and species like Flabellina affinis and similars, with cerata of each group coming from a stalk or pod. Although Furfaro et al. consider the species of both clades belonging to the genusFlabellina within the family Flabellinidae, Korshunova et al. distinguishes two families: Coryphellidae and Flabellinidae sensu stricto, also creating many different genera in these families to include the species they study. Its taxonomic proposal, curiously, solves the problems found by Furfaro et al.
In a way, both papers complement to each other, although in the paper by Korshunova et al. it is evident the lack of studies on tropical flabellinid species and those from southern America and Africa, so the subject has not been settled. The proposal to create new genera to collect small groups of species, instead of multispecific genera, seems to be the trend in some of the phylogenetic works of recent years. We hope to see new papers expanding the knowledge on the aeolidaceans soon. A detailed discussion of this exciting controversy can be found at (


  • Flabellina baetica (García Gómez, 1984)


This eolidacean species can reach 3 cm in length. The body is hyaline white so it can see inside the pink or cream internal organs. Oral palps, propodial pals and rhinophores are also whitish. The rhinophores have short rounded and irregular protuberances on all its surface except in a slightly sinuous groove that runs along the entire dorsal midline. There are about 7 groups of ceratas on each side of the body and each of them emerges from a peduncle. The ceras are long and thin, hyaline white and inside the digestive gland looks like a fine cord of soft cream at the base that is darkened to become more or less dark red near the apex, where a white cnidosac is found. The tip of the ceras is sharp. The foot differentiates triangular propodial palps.


The specimens of this species are usually found on rocky bottoms on hydrozoans from which they feed. Very few biological data of the species are known. García-Gómez (1986) indicates that some specimens has been observed on the gymnoblastic hydrozoan of the genus Eudendrium; this same author describes the egg-mass as a long cord, somewhat curled and irregularly wrapped, 1 mm high and with ovigerous capsules of 90-100 microns containing a single white egg.


  • Baenopsis, derived from the specific name of Flabellina baetica, the type species of this genus, named after the ancient Roman province “Baetica“.
  • Baetica. Name of an ancient Roman province formed under Augustus, circa 15-12 BC, after the division of the Lusitania from the Hispania Ulterior. The land area of the Roman province corresponded to more than 75% of the current Andalusia (Spain), specifically it included the full provinces of Huelva, Seville, Cadiz, Malaga and Cordoba, the western half of Granada and Jaen and a fifth of that of Almería, and a quarter of the current Extremadura (south of Badajoz).

We only know documented reports from the Straits of Gibraltar, but there are unpublished observations by Dr. César Megina of the Sevilla University in the Western Andalucia shores.

Known georeferenced records of the species: Baenopsis baetica
: GROC 2010-2011
: Enric Madrenas
: João Pedro Silva
: Bernard Picton
: Manuel Ballesteros.
: M@re Nostrum
: Altres fonts
: Marine Regions

References for the species: Baenopsis baetica

    Andalucía (Atl.): Megina (unpubl. data). Gibraltar: García-Gómez (1984b, 1986a, 2002), García-Gómez et al. (1989), Megina (unpubl. data).

    General: Cervera, Templado, Garcia-Gomez, Ballesteros, Ortea, Garcia, Ros, & Luque, 1988:[P]; Garcia-Gomez, 1986:42; Perrone, 1990b:25

    Sources: Cervera et al., 2004, Ballesteros, 2007 & 2016, McDonald, 2006 and other sources.


    Western Mediterranean:
    Eastern Mediterranean:
    Atlantic Ocean:
This chart displays the observation probability for Baenopsis baetica based on our own records.

More pictures


Further reading

Cite this article as:

Ballesteros, Manuel, Enric Madrenas, Miquel Pontes (2012-2018) "Baenopsis baetica" in OPK-Opistobranquis, Published: 18/01/2015, Accessed: 20/01/2018 at (

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