''Berthella plumula'', commonly known as yellow-plumed sea slug, is a gastropod mollusc usually found on rocky coasts in the

infralittoral The littoral zone or nearshore is the part of a sea, lake, or river that is close to the shore. In coastal ecology, the littoral zone includes the intertidal zone extending from the high water mark (which is rarely inundated), to coastal are ...

zone and which can live up to 30m depth.

Description

''Berthella plumula'' is an oval-shaped sea slug with an internal shell, which can be up to long. The body is up to and has a cream to orange colour and often displays reticulate markings. The head is flat and a large oral veil lies between the propodium and the

mantle A mantle is a piece of clothing, a type of cloak. Several other meanings are derived from that. Mantle may refer to: *Mantle (clothing), a cloak-like garment worn mainly by women as fashionable outerwear **Mantle (vesture), an Eastern Orthodox ve ...

. The rhinophores are protruding and enrolled. The species has acid glands in the skin which secrete sulphuric acid for protection in case of danger.

Distribution

''Berthella plumula'' is found in the north-eastern Atlantic, the Mediterranean Sea, the English Channel and the North Sea.

Behavior

Diet

''Berthella plumula'' is a slow moving predator which scrapes its

radula The radula (, ; plural radulae or radulas) is an anatomical structure used by molluscs for feeding, sometimes compared to a tongue. It is a minutely toothed, chitinous ribbon, which is typically used for scraping or cutting food before the food ...

on rocks to feed on colonial ascidians of the genus ''

Botryllus ''Botryllus'' is a genus of colonial ascidian tunicates in the family Styelidae. Species Species in this genus include: * '' Botryllus arenaceus'' Monniot, 1988 * '' Botryllus aster'' Monniot, 1991 * '' Botryllus closionis'' Monniot, Monniot ...

'' as well as on '' Oscarella'' sponges.

Reproduction

The species is

hermaphrodite In reproductive biology, a hermaphrodite () is an organism that has both kinds of reproductive organs and can produce both gametes associated with male and female sexes. Many Taxonomy (biology), taxonomic groups of animals (mostly invertebrate ...

and the two individuals reciprocally fecundate each other by exchanging their sperm. The reproductive period occurs in spring. The laying is tube-shaped and the eggs are displayed in spiral.

Similar species

''Berthella plumula'' can be confused with ''

Berthella stellata ''Berthella stellata'' is a species of sea slug in the family Pleurobranchidae. It is found in shallow water in the Mediterranean Sea, the western Atlantic Ocean and the tropical and subtropical Indo-Pacific region. Taxonomy This sea slug was Sp ...

'', which is smaller and displays a small white mark on its back, and with '' Berthellina edwardsii'', which is usually bigger and more red.

References

{{Taxonbar, from=Q5063374 Pleurobranchidae Molluscs of the Atlantic Ocean Molluscs of the Mediterranean Sea Gastropods described in 1803 Taxa named by George Montagu (naturalist)