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The Kerry slug or Kerry spotted slug, scientific name ''Geomalacus maculosus'', is a rare species of medium-sized to large air-breathing land slug. It is a terrestrial pulmonate gastropod mollusc in the family Arionidae, the roundback slugs. An adult Kerry slug generally measures 7–8 cm (2.8–3.2 in) in length and is dark grey or brownish in colour, with yellowish spots. The internal anatomy of the slug shows some unusual features, and some characteristic differences from the genus ''Arion'', which is the type genus of the family Arionidae. The Kerry slug was described in 1843, rather late compared to many other relatively large land gastropods that form a part of the fauna of the British Isles; this is one indication of this slug's rarity and its secretive habits. Although the distribution of this slug species does include some wild habitats in southwestern Ireland (e.g. in County Kerry), the species is more widespread in north-west Spain and from central to northern Portugal. However, it is not found anywhere between Ireland and Spain. The species appears to require environments that have high humidity and acidic soil (soil with no calcium carbonate in it). The slug is mostly nocturnal or crepuscular, although in Ireland it is active on overcast days. It feeds on lichens, liverworts, mosses and fungi, which grow either on boulders or on tree trunks. This rare species is officially protected by conservation laws in each of the three countries in which it occurs. However, the survival of the Kerry slug is nonetheless threatened because it lives only in completely wild, unspoiled habitat of a particular type: acidic woodlands and moorlands that support the species of lower plants on which the slug relies for food. This habitat type is itself at risk from a number of different factors, ranging from climate change to the construction of roads. Attempts have been made to establish breeding populations in captivity, to help ensure the survival of this slug species, but with only limited success. ==Taxonomy== The Kerry slug is a gastropod, as are all other snails and slugs, including slugs and snails that live in saltwater, those that live in freshwater, and those that live on the land. This is a land slug which breathes air, a pulmonate. It is in the clade Stylommatophora, which means that its primitive eyes or eye spots are carried on the tips of its two upper tentacles. Despite superficial similarities, not all land slugs are in the same family or superfamily. The Kerry slug is an arionid, or round-backed slug; it has no keel on its back, in contrast to the land slugs in the family Limacidae and Agriolimacidae. It also shares numerous internal anatomical features with slug species in other genera within the family Arionidae, including the ''Arion'' slugs, which are most typical of the family. The Kerry slug's scientific name or binomial name is ''Geomalacus maculosus''. It is in the genus ''Geomalacus'', a name which literally means "earth mollusc". Its specific name ''maculosus'' means "spotted", from the Latin word ''macula'' "spot". The English language vernacular name (or common name) is derived from the name of County Kerry, which is the county in the southwest of Ireland where this species was first collected, and which is also the type locality, as mentioned in the original description. The scientific name of the species is also sometimes written as ''Geomalacus (Geomalacus) maculosus''. This is because the genus ''Geomalacus'' contains two subgenera: the nominate subgenus (subgenus of the same name) ''Geomalacus'' and a second subgenus ''Arrudia'' Pollonera, 1890. The subgenus ''Geomalacus'' contains only one species, the Kerry slug. The subgenus ''Arrudia'' includes three species. This slug species was originally described and named from specimens collected in Ireland. In 1842, an Irish naturalist named William Andrews (1802–1880) sent material that he had found at Caragh Lake in County Kerry to the Irish naturalist George James Allman,〔 who then introduced the slug to science as a new species. The Kerry slug has been included in molecular phylogenetic studies since 2001. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Kerry slug」の詳細全文を読む スポンサード リンク
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