|
Arion ater (Linnæus, 1758)
|
|
Species name:
|
Arion ater (Linnæus, 1758)
|
|
|
Taxon name:
|
Limax ater Linnæus, 1758
|
|
Originally described in:
|
Linnæus, C. 1758. Systema naturæ per regna tria naturæ, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Tomus I. Editio decima, reformata. - pp. [1-4], 1-824. Holmiæ. (Salvius).
|
|
Distribution:
|
N and NW Europe, in Scandinavia becoming coastal beyond about 61° N
|
|
Diagnosis:
|
Slug deeply black, rarely dark brown, foot-fringe black, tubercles large and elongate. Sole blackish grey. Juveniles ivory whitish with black head, quickly they become greyish, half-grown animals are often black like adults.
Atrium and vagina considerably narrower than spermatheca, oviduct narrow, spermatheca spherical.
Arion lusitanicus is never black, juveniles are characteristically banded.
|
|
Size:
|
Up to 130 mm long
|
|
Biology:
|
Prefers humid habitats, usually in woods. In Britain in natural habitats of moderately humid habitats, open and in forests, usually in wilder and harsher places than A. rufus, in the west and north. In Spain as a synanthope, feeding on desintegrating and green plants, in many zones a horticultural pest. Up to 1800 m in Alps and Pyrenees.
Eggs are laid under mosses, exceptionally also inside the soil, in batches (every 1-3 weeks from August to October) of up to 150 eggs, later in the season only around 20 eggs, juveniles hatch after at least 27 days, this takes longer with cold temperatures, maturity is reached after 9 months, colpulation in early summer, repeated copulations are not necessary, slugs die shortly after the last eggs were laid, life span not more than a year.
|
|
Threatened:
|
In Britain (at least until 1999) one of the most widespread and frequent terrestrial molluscs, records by Kerney 1999 include Arion rufus.
Vulnerable in Niedersachsen.
|
|
Family:
|
Arionidae
|
|
Higher group:
|
Gastropoda
|
|
Comments:
|
Sympatric occurrences with Arion rufus in Denmark, N Germany (Schleswig-Holstein) and S England, in other parts of Britain they seem to interbreed.
References: Künkel 1908, Kerney & Cameron 1979: 104, Jungbluth et al. 1989: 122, Falkner 1990: 194, Castillejo 1997: 70, Kerney 1999: 120, Welter-Schultes 2012: 473 (range map).
|
