Tergipes tergipes

Tergipes tergipes (Forsskål in Niebuhr, 1775)

Tergipes tergipes by Bernard Picton

Taxonomy
 

Superdomain

Biota  

 

Kingdom

Animalia  

 

Phylum

Mollusca  

 

Class

Gastropoda  

 

Subclass

Heterobranchia  

 

Infraclass

Euthyneura  

 

Subterclass

Ringipleura  

 

Superorder

Nudipleura  

 

Order

Nudibranchia  

 

Suborder

Cladobranchia  

 

Superfamily

Fionoidea  

 

Family

Tergipedidae  

 

Genus

Tergipes  

 

Species

Tergipes tergipes  (Forsskål in Niebuhr, 1775)

 
 Classification according to Bouchet et al. (2017)
Taxonomic source: World Register of Marine Species (AphiaID: 141641).

Taxonomic note: The phylogenetic analyses performed by Cella et al. (2016) revealed that the traditional Tergipedidae family is polyphyletic and belongs to a larger monophyletic clade including members of the traditional families Eubranchidae, Fionidae and Calmidae; this was an unexpected result, since the validity of these taxa and their distinctness from the Tergipedidae was never questioned before. They proposed to join the families Tergipedidae, Eubranchidae, Calmidae and Fionidae under the name of Fionidae. Within Fionidae, obtained results demonstrated the need of developing a new classification as previous classifications (for instance, separating Catriona, Cuthona and Trinchesia as distinct taxa) were inconsistent with the resulting phylogeny. Analyses also recover a clade (Tenellia) that includes all members of the genera Tenellia, Trinchesia, Phestilla, Catriona and the majority of described and undescribed Cuthona species. New genera Rubramoena, Abronica and Tergiposacca are proposed to group other species. This molecular study also suggests that Fionidae is rich in cryptic species complexes, difficult to separate by traditional taxonomic characters, and a great previously undetected species diversity.
A few months later Korshunova et al. (2017) take up the study of the phylogeny of the Tergipedidae and using not only molecular data but also morphological and ontogenetic data they severely criticise the work by Cella et al. (2016), proposing to reinstate the families Calmidae, Eubranchidae, Fionidae, Tergipedidae, Cuthonidae, Cuthonellidae and Trinchesiidae, the latter being the most abundant in specific taxa. They also reinstate the genera Catriona, Diaphoreolis, Phestilla and Trinchesia that in the paper by Cella et al. (2016) had been included in the genus Tenellia. Korshunova et al. also describe a new genus, Zelentia that includes Z. pustulata (type species Eolis pustulataAlder & Hancock, 1854), Z. fulgens (MacFarland, 1966) and a new species from the Barents Sea, Z. ninel, indicating important p-distances among the three species (between 10.49% and 13.83%). All previous genera, Korshunova et al. (2017) consider them within the family Trinchesiidae. They also question the validity of the Rubramoena genus of Cella et al.
The position of WoRMS is conservative, maintaining the families Cuthonidae, Calmidae, Cuthonellidae, Eubranchidae, Fionidae, Pseudovermidae, Tergipedidae and Trinchesiidae within the superfamily Fionoidea. The European species that, until recently, were considered as Cuthona, WoRMS considers them within the genus Trinchesia, as T.albopunctata, T.caerulea, T.foliata, T.genovae, T.granosa, T.ilonae, T.miniostriata and T.ocellata. Rubramoena is also considered a valid genus in WoRMS. These opinions are those that we accept in OPK while no other more conclusive data are available.

Synonyms

  • Aeolis neglecta Lovén, 1846
  • Eolidia despecta Johnston, 1835
  • Limax tergipes Forsskål in Niebuhr, 1775 (original)
  • Psiloceros claviger Menke, 1844
  • Tergipes despectus (Johnston, 1835)
  • Tergipes lacinulatus de Blainville, 1824

Description
This is a very small species of aeolidacean, not exceeding 5 mm in length, that has a narrow and elongated body. The general coloration is yellowish-white but the transparent integument allows the observation of most cream coloured viscera from the second right cerata almost to the tail, and the dark green digestive gland, in the form of a serpentine shaped cord that runs almost the entire length of the body and whose branches run into every cerata. Oral palps are short and translucent while the rhinophores are long and thin and are soft brown pigmented on the base. The back and sides of the head are also finely coloured in light brown and there are also two elongated dark brown spots ranging obliquely from the rear base of the rhinophores to the insertion of the first cerata; in these brown spots are where the eyes are located. The shape and arrangement of the cerata is characteristic of this species: only one series of cerata on each side of the body, symmetrically placed the first two and the rest alternating from one side to the other, being the right cerata somewhat more advanced than the left side cerata. The cerata are long and thin, narrower at the base, within them the dark green digestive gland is visible. The genital orifice is located below and slightly forward of the first right cerata. The foot is semi-transparent, it does not form propodiales tentacles in its forward zone and the tail is long.

Biology
This small aeolidacean has been observed living over several species of hydroids like Aglaophenia pluma, Bougainvillia ssp., Campanularia sp., Clava multicornis, Gonothyraea loveni, Laomedea flexuosa, L. gelatinosa, L. loveni, Obelia dichotoma, O . longissima, Sertularia sp. and polyps of Sarsia eximia. Some of these species are epibionts of bivalve molluscs such as mussels Mytilus galloprovincialis and could be their food. Although it is a species that is not often seen, possibly due to their small size and mimicry with the hydrarian colonies it lives on, it has been sometimes cited as gregarious. Spawning takes the form of a transparent reniform capsule and 2 mm in length, containing 150 white eggs of 80-100 microns of diameter.

Distribution
This is a species that has a wide geographical distribution, having been cited on both sides of the Atlantic and in the Mediterranean. In the western Atlantic it has been cited from the Arctic, Newfoundland and down to the coast of New Jersey (USA), also in the coast of Brazil. In the eastern Atlantic coasts it has been cited in the shores of Denmark, Nederlands and Belgium, the British Isles and Ireland. In the Iberian Peninsula it has been cited in the Cantabrian area, along the Portuguese coast, in Andalusia, the Levantine coast and Catalonia (it has been cited just once, at Sitges, over the hydrarian Obelia dichotoma epibiont of mussel shells). It has also been cited in the Ukrainian Black Sea coast.

Known georeferenced records of the species: Tergipes tergipes
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:

More pictures

Bibliography

Further reading

Cite this article as:

Ballesteros, Manuel, Enric Madrenas, Miquel Pontes (2012-2018) "Tergipes tergipes" in OPK-Opistobranquis, Published: 30/11/2012, Accessed: 14/11/2018 at (https://opistobranquis.info/en/xqYC8)

In order to copy this cite or text fragments you must be a registered user.