''Akera bullata'' is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

sea snail Sea snail is a common name for slow-moving marine gastropod molluscs, usually with visible external shells, such as whelk or abalone. They share the taxonomic class Gastropoda with slugs, which are distinguished from snails primarily by the ...

(or

sea slug Sea slug is a common name for some marine invertebrates with varying levels of resemblance to terrestrial slugs. Most creatures known as sea slugs are gastropods, i.e. they are sea snails (marine gastropod mollusks) that over evolutionary t ...

), a

marine Marine is an adjective meaning of or pertaining to the sea or ocean. Marine or marines may refer to: Ocean * Maritime (disambiguation) * Marine art * Marine biology * Marine debris * Marine habitats * Marine life * Marine pollution Military * ...

opisthobranch Opisthobranchs () is now an informal name for a large and diverse group of specialized complex gastropods which used to be united in the subclass Opisthobranchia. That taxon is no longer considered to represent a monophyletic grouping. Euopisth ...

gastropod The gastropods (), commonly known as snails and slugs, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, from freshwater, and from land. T ...

mollusk Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is e ...

in the family Akeridae, a family that is related to the

sea hare The clade Anaspidea, commonly known as sea hares ('' Aplysia'' species and related genera), are medium-sized to very large opisthobranch gastropod molluscs with a soft internal shell made of protein. These are marine gastropod molluscs in the ...

s. This species is the only

Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a Continent#Subcontinents, subcontinent of Eurasia ...

an representative of the genus ''

Akera ''Akera'' is a marine genus of sea hare in the family Akeridae, known from the late Callovian (Jurassic) to the recent periods.Gofas, S. (2012). Akera O.F. Müller, 1776. Accessed through: World Register of Marine Species at http://www.marinespe ...

''.

Distribution

This species occurs from

Norway Norway, officially the Kingdom of Norway, is a Nordic country in Northern Europe, the mainland territory of which comprises the western and northernmost portion of the Scandinavian Peninsula. The remote Arctic island of Jan Mayen and t ...

to the Canaries, and also in the

Mediterranean The Mediterranean Sea is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean Basin and almost completely enclosed by land: on the north by Western and Southern Europe and Anatolia, on the south by North Africa, and on the e ...

Ecology

This is a

herbivorous A herbivore is an animal anatomically and physiologically adapted to eating plant material, for example foliage or marine algae, for the main component of its diet. As a result of their plant diet, herbivorous animals typically have mouthpart ...

bottom dweller (up to 370 m deep), which feeds on

seagrass Seagrasses are the only flowering plants which grow in marine environments. There are about 60 species of fully marine seagrasses which belong to four families (Posidoniaceae, Zosteraceae, Hydrocharitaceae and Cymodoceaceae), all in the orde ...

es in the genera ''

Zostera ''Zostera'' is a small genus of widely distributed seagrasses, commonly called marine eelgrass, or simply seagrass or eelgrass, and also known as seaweed by some fishermen and recreational boaters including yachtsmen. The genus ''Zostera'' con ...

'' and ''

Posidonia ''Posidonia'' is a genus of flowering plants. It contains nine species of marine plants ("seagrass"), found in the seas of the Mediterranean and around the south coast of Australia. The APG system (1998) and APG II system (2003) accept this gen ...

''.

Description

The body has a maximum length of about 6 cm. Its color varies from gray to orange, with white or dark specks. Its fragile and smooth shell is white or brown. This sea hare is not an agile swimmer. It uses its broad

parapodia In invertebrates, the term parapodium ( Gr. ''para'', beyond or beside + ''podia'', feet; plural: parapodia) refers to lateral outgrowths or protrusions from the body. Parapodia are predominantly found in annelids, where they are paired, unjointed ...

(fleshy protrusions), held together funnelwise above the head, to paddle away when disturbed.

Synonyms

''Acera bullata'' is an orthographic variant with considerable currency. The NLBIF lists a large number of synonyms in addition to the above; including: ''Bulla akera'' (Gmelin, J.F., 1791),Marine Mollusca of the Faroes. p. 95. ''Bulla norwegica'' (Bruguière, J.G., 1789), ''Bulla canaliculata'' (Olivi, 1792), ''Bulla resiliens'' (Donovan, E., 1801), ''Bulla fragilis'' (Lamarck, J.B.P.A. de, 1822), ''Akera flexilis'' (Brown, 1844), ''Bulla hanleyi'' (Adams A. in Sowerby G.B. II, 1850/1855), ''Eucampe donovani'' (Leach, W.E., 1852), ''Bulla elastica'' (Sandri & Danilo, 1856), ''Acera bullata'' var. nana (Jeffreys, 1867), ''Acera elegans'' (Locard, 1886), ''Bulla farrani'' (Norman, 1890), ''Bulla globosa'' (Cantraine, F.J., 1840), ''Akera tenuis'' (Brusina, S., 1866) and ''Akera farrani'' (Winckworth, R., 1932).

References

Müller, O.F. (1776). ''Zoologica Danicae Prodromus seu Animalium Daniae et Norvegiae indigenarum characters, nomine, et synonyma imprimis popularium''. Havniae. XXXII, 274 pp., page(s): 242

Distribution

Ecology

Description

Synonyms

References

Further reading