''Arion'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of air-breathing land

slug Slug, or land slug, is a common name for any apparently shell-less Terrestrial mollusc, terrestrial gastropod mollusc. The word ''slug'' is also often used as part of the common name of any gastropod mollusc that has no shell, a very reduced ...

s in the family

Arionidae Arionidae, common name the "roundback slugs" or "round back slugs" are a taxonomic family of air-breathing land slugs, terrestrial pulmonate gastropod mollusks in the superfamily Arionoidea. Distribution The distribution of this family of s ...

, the roundback slugs. Most species of this

Palearctic The Palearctic or Palaearctic is a biogeographic realm of the Earth, the largest of eight. Confined almost entirely to the Eastern Hemisphere, it stretches across Europe and Asia, north of the foothills of the Himalayas, and North Africa. Th ...

genus are native to the

Iberian Peninsula The Iberian Peninsula ( ), also known as Iberia, is a peninsula in south-western Europe. Mostly separated from the rest of the European landmass by the Pyrenees, it includes the territories of peninsular Spain and Continental Portugal, comprisin ...

. Species can be difficult to distinguish from one another upon cursory examination, because individuals of a species can vary in color and there are few obvious differences between taxa. The color of an individual can be influenced by its diet. Some ''Arion'' are known as

pests PESTS was an anonymous American activist group formed in 1986 to critique racism, tokenism, and exclusion in the art world. PESTS produced newsletters, posters, and other print material highlighting examples of discrimination in gallery represent ...

, such as ''A. lusitanicus'' auct. non Mabille (= ''A. vulgaris''), which damages agricultural crops and

ornamental plant Ornamental plants or ''garden plants'' are plants that are primarily grown for their beauty but also for qualities such as scent or how they shape physical space. Many flowering plants and garden varieties tend to be specially bred cultivars th ...

s, and ''A. rufus'', a familiar

garden A garden is a planned space, usually outdoors, set aside for the cultivation, display, and enjoyment of plants and other forms of nature. The single feature identifying even the wildest wild garden is ''control''. The garden can incorporate bot ...

pest. ''Arion'' slugs are often transported internationally in shipments of plant products and mushrooms. ''Arion'' slugs have been identified in North America and Australia as

invasive species An invasive species is an introduced species that harms its new environment. Invasive species adversely affect habitats and bioregions, causing ecological, environmental, and/or economic damage. The term can also be used for native spec ...

, altering the plants of ecosystems through seed predation and competing with native slugs.

Species

There are approximately 40 species in the genus. Species include: * ''

Arion ater The black slug (also known as black arion, European black slug, or large black slug), ''Arion ater'', is a large terrestrial gastropod mollusk in the family Arionidae, the round back slugs. Many land slugs lack external shells, having a vestigi ...

'' (Linnaeus, 1758) – black slug * '' Arion circumscriptus'' Johnston, 1828 – brown-banded arion * ''

Arion distinctus ''Arion distinctus'' is a species of air-breathing land slug in the family (biology), family Arionidae, sometimes known as the roundback slugs. It is a terrestrial molluscs, terrestrial pulmonate gastropod mollusc. Several common name, vernacular ...

'' Mabille, 1868 – darkface arion * '' Arion fasciatus'' (Nilsson, 1823) – orange-banded arion * '' Arion flagellus'' Collinge, 1893 * '' Arion fuscus'' (O.F.Müller, 1774) * ''

Arion hortensis ''Arion hortensis'', also known by its common name the "garden slug", "small striped slug" or "black field slug" is a species of small air-breathing land slug, a terrestrial pulmonate gastropod mollusk in the family Arionidae, the roundback slu ...

'' Férussac, 1819 – small striped slug * '' Arion intermedius'' Normand, 1852 ( syn. ''Arion alpinus'' Pollonera, 1887Manganelli, G., et al. (2010)
The status of ''Arion alpinus'' Pollonera 1887, and re-description of ''Arion obesoductus'' Reischütz 1973 (Gastropoda, Arionidae).
''Journal of Conchology'' 40, 269–76.) – hedgehog slug * ''

Arion lusitanicus ''Arion lusitanicus'', also known by its common name Portuguese slug, is a species of air-breathing land slug, a terrestrial molluscs, terrestrial pulmonate gastropod mollusc, mollusk in the family Arionidae. Distribution ''Arion lusitanicus'' ...

'' Mabille, 1868 * '' Arion obesoductus'' (syn. ''Arion alpinus'' auctt. non Pollonera, 1887) * ''

Arion occultus ''Arion occultus'' is a species of small air-breathing land slug, a terrestrial pulmonate gastropod mollusk in the family Arionidae, the roundback slugs. Distribution This species occurs in: * Ireland; appears to be introduced in Ireland, but ...

'' R.Anderson, 2004 * ''

Arion owenii ''Arion owenii'' is a species of small air-breathing land slug, a terrestrial pulmonate gastropod mollusc in the family Arionidae, the roundback slugs. Description Note. In slugs it is often difficult to establish good criteria for identifying ...

'' Davies, 1979 – warty arion * ''

Arion rufus The red slug (''Arion rufus''), also known as the large red slug,Arion silvaticus ''Arion silvaticus'' is a species of air-breathing land slug, a terrestrial pulmonate gastropod mollusk in the family Arionidae. Description Note. In slugs it is often difficult to establish good criteria for identifying species using external ...

'' Lohmander, 1937 – forest arion * ''

Arion simrothi ''Arion simrothi'' is a species of air-breathing land slug, a terrestrial pulmonate gastropod mollusk in the family Arionidae, the round-back slugs. Distribution This species is found only in Germany Germany, officially the Federal Rep ...

'' Künkel, 1909 * ''

Arion subfuscus ''Arion subfuscus'' is a species of land slug. It forms a species complex with '' Arion fuscus''. It is native to Eurasia, and has been introduced to eastern North America North America is a continent in the Northern Hemisphere, North ...

'' (Draparnaud, 1805) – dusky arion * ''

Arion transsylvanus ''Arion transsylvanus'' is a species of terrestrial slug in the family Arionidae, the roundback slugs. It is a member of the '' Arion subfuscus'' species complex and known mostly from Transylvania in Romania, where it appears to be the only spe ...

'' Simroth, 1885 * '' Arion vulgaris'' Moquin-Tandon, 1855 (syn. ''Arion lusitanicus'' auct. non Mabille) – Spanish slug

Also included

*'' Arion vejdorskyi'', a taxon with unclear taxonomic position

Etymology

The name ''Arion'' is in reference to Aelion's ''De Natura Animalium,'' which features a story about ''areíones -'' snails which leave their shells behind to feed, thus outsmarting predators who attack the empty shells.

References

{{DEFAULTSORT:Arion (Genus) Gastropod genera Taxa named by André Étienne d'Audebert de Férussac