Duvaucelia manicata

Duvaucelia manicata (Deshayes, 1853)

Synonyms

• Candiella villafranca Vayssière, 1901
• Duvaucelia gracilis Risso, 1826
• Nemocephala marmorata Costa A., 1867
• Tritonia moesta Bergh, 1884
• Tritonia manicata Deshayes, 1853

Description
The body, like in other species of the same genus, is tall and with a square section. Animals are small and can reach a size of just over 10 mm long. The background color of the body is whitish but the dorsum appears darkened by an elongated and of irregular contour dark brown, almost black, stain, continuous in many specimens, which runs from the back of the head to the tail. Spots of the same color are also appreciated in front of the rhinophores and on the side walls of the body, in this case in the form of small irregular spots and, in some animals, aligned as a discontinuous stripe. In some specimens the spots on the dorsum and sides of the body could be reddish. The head has a semitransparent cephalic veil with 4-6 fingerings in the front. The rhinophores are short and cylindrical, with 2-3 poorly developed lamellae and a small number of digitations directed obliquely and forward. The rhinophore is surrounded at its base by a wide whitish sheath which also could be coloured in dark brown pigment. The eyes are seen by transparency in the center of the base of the rhinophores. The back has 3-4 white little branched processes on each side. The genital opening and anus are located on the right side of the body, at the height of the first and second dorsal process. The foot is rounded in the front area and is broad in the tail, widely protruding underneath the dorsum; it is coloured whitish.

Biology
This species is usually found in dimly lit shallow rocky walls with an abundance of seaweeds, sponges and hydrarians. In these walls abound anthozoan cnidarians of the stoloniferous group, of the genus Cornularia and Clavularia, on which it apparently feeds. It can also be found between rhizomes of Posidonia oceanica.

Etymology

• Duvaucelia. In honor of Alfred Duvaucel (1792-1824), son of Anne-Marie Duvaucel’s marriage to Baron de Cuvier, with whom he was in India and Sumatra collecting objects of natural history for the Museum of Paris until his death, in Java, at the age of 31.
• Manicata. From Latin “manicatus”, with sleeves, alluding the rhinophoric sheaths.

Distribution
This species is mainly distributed across all Mediterranean coastlines but there are cites from the Atlantic coast of Morocco and in the British Isles. In the Iberian Peninsula it has been found in all coastal areas and also in the Balearic islands. In Catalonia it has been cited in several localities of the Costa Brava (Es Caials, Illes Medes, Estartit, Cala Aiguablava, Llafranc, Cala Santa Cristina, Tossa de Mar) and also in Vilassar de Mar.

Known georeferenced records of the species: Duvaucelia manicata
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

Similar species
Due to its dark coloration, it cannot be confused with any other species.

Abundance

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