Berthella plumula

Berthella plumula (Montagu, 1803)

• Berthella porosa de Blainville, 1824
• Bulla plumula Montagu, 1803 (original)
• Cleanthus montagui Leach, 1852
• Lamellaria kleciachi Brusina, 1866
• Pleurobranchus brevifrons Philippi, 1844
• Pleurobranchus fleuriausi d’Orbigny, 1837
• Pleurobranchus perforatus Philippi, 1844
• Pleurobranchus plumula (Montagu)
• Sigaretus stomatellus Risso, 1826

Taxonomic note: Following the study by Ghanimi et al. (2020) of the Berthella stellata species complex, it turns out that the species known so far as Berthella plumula (Montagu, 1803) is actually a complex of two differentiated species; the name B. plumula is retained for specimens from the Atlantic, while the name Berthella perforata (Philippi, 1844) is proposed for specimens from the Mediterranean.

Description
This species can grow up to 35 mm. The overall body color is whitish or pale, but orange animals are not rare. Light brown viscera can be seen, by transparency, in the center of the dorsum. The mantle is quite flat and is characterized by having a lattice pattern consisting of differently shaped small depressions, that provide the dorsum a porous appearance. With a binocular microscope, numerous star like spicules can be seen under the mantle epidermis. The inner shell can also be observed in the central area of the mantle. The head veil, the rhinophores, the branquia and foot are whitish or yellowish. The gill is free for about one third of its total length and has about 20 lamellae on either side of the central shaft.

Biology
It is an sporadical finding, usually under stones or associated to shallow Posidonia oceanica rhizomes. The foot of this species has glands that produce acidic defensive secretions. Little is known about the biology of this species, which could feed on sponges and colonial tunicates.

Etymology

• Berthella. Probably dedicated to Sabin Berthelot (1794-1880), a French naturalyst who enrolled the Navy and participated in the Napoleonic wars. He lived part of his life at the Canary islands, in his post as French consul in Tenerife. The abbreviation “Berth” is used to indicate Sabin Berthelot as an authority in the scientific botanical description and classification. He wrote the “Historia Natural de Canarias” and directed the Botanical Garden of Puerto de la Cruz.
• Plumula. Latin origin, the aftershaft of a feather. The first bud, or gemmule, of a young plant; the bud, or growing point, of the embryo, above the cotyledons.

 Distribution
This species inhabits all the European Atlantic coasts. Mediterranean specimens formerly included in this species have been classified, after the work by Ghanimi et al (2020) as B.perforata. In the Iberian Peninsula it has been observed and collected along the entire Atlantic coast, also in Madeira, Azores and the Canary Islands.

Known georeferenced records of the species: Berthella plumula

Sources:
OBIS GROC 2010-2011 Enric Madrenas João Pedro Silva Bernard Picton GBIF	OPK VIMAR Manuel Ballesteros M@re Nostrum Altres fonts Marine Regions

More pictures

Berthela plumula (Atlantic) by Carlos Fernández-Cid

Bibliography

1246567 Berthella plumula 1 eunomia-revista-en-cultura-de-la-legalidad 50 creator asc 1 394 https://opistobranquis.info/wp-content/plugins/zotpress/
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: