Tenellia maua

Tenellia maua  (Ev. Marcus & Er. Marcus, 1960)

Tenellia maua @ Lake Worth Lagoon, Florida 23-09-2016 by Ariane Dimitris
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: Fionoidea Gray, 1857
Family: Fionidae Gray, 1857
Genus: Tenellia A. Costa, 1866
Species: Tenellia maua  (Ev. Marcus & Er. Marcus, 1960)

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 previously undetected species diversity.

Korshunova et al. (2017) present some phylogenies based on morphological characters (which may be parological) to reclassify this group. In addition, for molecular phylogeny they use the COI gene (not useful to separate genera) instead of i.e. the H3 gene, so the hypotheses presented are weak. For this reason we keep the last classification until the status of this species is cleared.


  • Catriona maua   Ev. Marcus & Er. Marcus, 1960

This is a small aeolidacean, with a maximum reported size of 12mm.  It has a translucent white or yellowish body with opaque white irregular patches. The head is narrow as in other species of the genus. The head tentacles are short, colored with opaque white and directed to the sides. Rhinophores are finger shaped, smooth and short, with the anterior side colored opaque white and a bright red or orange stripe on the posterior side of their base. The eyes are black. The anterior angles of the foot are rounded; the foot is not as broad as the body, and the tail is pointed. The club shaped cerata (wider above the middle) are numerous, there could be up to 11 rows of cerata on each side of the body, the most populated rows are 2 to 4, and the less populated are the ones closer to the tail. The cerata do not cover the anterior body region nor the tip of the tail. Anus and nephroproct are located close to the innermost cerata of the 5th right row, while the gonopore is between the first and the second right rows. The bright red oesophagus is visible by transparency, as are the brown and smooth diverticula of the digestive gland in the base of cerata.

It is generally found in shallow water (from 1 to 8 meters depth) on sponges or hydrozoan branches. Thompson (1980) collected this species in Jamaica from Pennaria hydrozoans, while Marín & Ros (1987) collected it on Ventromma halecioides in the Mediterranean. This species is more freqüent between November and January, and from April to June. The spawn is a one turn coil (Marcus & Marcus, 1960) or kidney shaped (Marín & Ros, 1987) with about 70 eggs of 100 microns of diameter. Hatching occurs after 16-17 days at 16ºC.


  • Maua, of uncertain origin, seems related to cats.

Tenellia maua has an amphi-Atlantic distribution. It has been cited in the Western Atlantic at Miami, USA (Marcus & Marcus, 1960), Curaçao and Bonaire (Marcus & Marcus, 1963), Jamaica (Edmunds, 1964; Thompson, 1980), Barbados (Edmunds & Just, 1983) and Bahamas (Redfern, 2001). In the Eastern Atlantic it has been cited in Gran Canaria, Tenerife and La Gomera (Canary Islands by Ortea et al, 2002), Azores (Malaquias et al., 2009), Cape Verde (Ortea et al., 2002) and the Atlantic Southern coast of Spain (Cervera, unpublished data). In the Mediterranean it has been cited in the Gulf of Naples, Italy (Schmekel, 1968; Schmekel & Portmann, 1982) and in the Mar Menor, Murcia, Spain (Marín & Ros, 1987).

Known georeferenced records of the species: Tenellia maua (z-200).
: GROC 2010-2011 : VIMAR
: Enric Madrenas : Manuel Ballesteros.
: João Pedro Silva : M@re Nostrum
: Bernard Picton : Other sources
: GBIF.ORG : Marine Regions


        Western Mediterranean:1 Stars
        Eastern Mediterranean:0 Stars
        Atlantic Ocean:1 Stars
This chart displays the observation probability for Tenellia maua
based on our own records.


Tenellia maua @ Lake Worth Lagoon, West Palm Beach, Florida, USA by Ariane Dimitris

More pictures


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, Manuel, Enric Madrenas, Miquel Pontes et al. (2012-2017) "Tenellia maua" in OPK-Opistobranquis, Published: 16/05/2016, Accessed: 18/10/2017 at (http://opistobranquis.info/en/ZEgee)

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