Arion vulgaris (Spanish slug)
- Summary of Invasiveness
- Taxonomic Tree
- Notes on Taxonomy and Nomenclature
- Distribution Table
- History of Introduction and Spread
- Risk of Introduction
- Habitat List
- Hosts/Species Affected
- Host Plants and Other Plants Affected
- Growth Stages
- List of Symptoms/Signs
- Biology and Ecology
- Latitude/Altitude Ranges
- Natural enemies
- Notes on Natural Enemies
- Means of Movement and Dispersal
- Pathway Causes
- Pathway Vectors
- Impact Summary
- Economic Impact
- Environmental Impact
- Social Impact
- Risk and Impact Factors
- Uses List
- Detection and Inspection
- Similarities to Other Species/Conditions
- Prevention and Control
- Gaps in Knowledge/Research Needs
- Links to Websites
- Distribution Maps
Don't need the entire report?
Generate a print friendly version containing only the sections you need.Generate report
PicturesTop of page
IdentityTop of page
Preferred Scientific Name
- Arion vulgaris Moquin-Tandon 1855
Preferred Common Name
- Spanish slug
Other Scientific Names
- Arion lusitanicus Mabille 1868
International Common Names
- Spanish: babosa lusitana
- French: arion rouge; limace ibérique; limace noire; limace rouge
Local Common Names
- Germany: Spanische Wegschnecke
- UK: Iberian slug
- ARIOLU (Arion lusitanicus)
Summary of InvasivenessTop of page
Arion vulgaris is a slug native to southern France and Catalonia in Spain, that has since spread to much of central, northern and eastern Europe. It is considered to be invasive across western and central Europe, from the Pyrenees to eastern Poland and from southern France to north Italy, Austria and Slovakia and within an isolated range in eastern Bulgaria.
The invasiveness of A. vulgaris is related to several factors. One is its propensity for hybridizing with native large Arion species to produce vigorous adaptable forms. Its ability to colonize environments disturbed by human activities is also of major importance – for example in one study 99% of Swedish records were from synanthropic habitats and only 1% from natural woodlands – as proximity to humans comes with the possibility of passive dispersal through trade, illegal dumping (fly-tipping) of garden waste and particularly transport on living plants. The garden centre trade and horticulture are particularly implicated. In Poland, there is evidence from studies of molecular diversity that A. vulgaris has originated from repeated, separate introductions from other parts of Europe. The ability of A. vulgaris to utilize a great variety of food sources and types has been well-documented and must aid dispersal and colonization. In gardens, plant diversity has been shown to be positively associated with abundance of A. vulgaris.
Taxonomic TreeTop of page
- Domain: Eukaryota
- Kingdom: Metazoa
- Phylum: Mollusca
- Class: Gastropoda
- Subclass: Pulmonata
- Order: Stylommatophora
- Suborder: Sigmurethra
- Unknown: Arionoidea
- Family: Arionidae
- Genus: Arion
- Species: Arion vulgaris
Notes on Taxonomy and NomenclatureTop of page
This species is widely known as the Lusitanian slug Arion lusitanicus Mabille, 1868. However, the name lusitanicus can no longer be applied. A re-description of lusitanicus sensu Mabille, based on topotypes from its type locality at Setubal, Serra da Arrábida, Portugal (Castillejo, 1997, 1998) has shown that Portuguese lusitanicus has a very different spermatophore and internal morphology from the central and west European species to which this name was applied by Altena (1956) and then by subsequent authors. The distinction between topotypic Arion lusitanicus and Arion ‘lusitanicus’ from north-west Europe has been confirmed by phylogenetic analysis (molecular studies) through ITS1 sequencing (Quinteiro et al., 2005; Colomba et al., 2007), and more recently using mitochondrial (cytochrome oxidase1) and nuclear (Zinc Finger) markers (Pfenninger et al., 2014). Falkner et al. (2002) proposed that the pest species in north-west Europe is called vulgaris Moquin-Tandon, 1855 as this appears to be the first available name that can be unambiguously applied. This is possible because Moquin-Tandon (1855), unusually among early authors, figured the highly diagnostic spermatophore in his description.
British authors, including Quick (1960), have confused vulgaris with Arion flagellus Collinge, a large Arion that inhabits the British Isles and northern Iberia, but has not so far been found elsewhere in Europe nor further afield. Some of Quick’s drawings of ‘lusitanicus’, particularly of the spermatophore (p. 142), actually relate to flagellus. This has clearly been a source of confusion and the reader is directed to Davies’ (1987) paper that first resolved the problem and gives a very detailed account of the distinguishing features and reproductive biology of flagellus and vulgaris (formerly lusitanicus).
DescriptionTop of page
Pneumostome located on the right-hand side of the mantle and near the front margin; keel absent; mantle granular. Foot fringe broad, heavily lineolated, similar colour to the dorsal surface. Juveniles have dark lateral bands with paler bands on the sides above and below these - distinguishing them from juvenile A. rufus and juvenile and adult A. subfuscus. Body colour is variable - yellowish, greyish, chocolate, reddish, brownish (but never greenish as in A.flagellus). Adults are normally unbanded, colour of the upper surface a uniform yellowish-brown, brown, reddish-brown or dark-brown, rarely black. Eggs are white, slightly transparent, soft-shelled, ca. 2.5 mm in diameter, noticeably larger than the eggs of A. flagellus (ca. 2 mm; Briner and Frank, 1998a).
Hatchlings are ca. 5 mm long when crawling. The adults are 6-12 cm long and normally weigh 5-15 g (extremes: 3-27 g)
DistributionTop of page
Moquin-Tandon’s description of A. vulgaris relates to a species inhabiting southern France (Moquin-Tandon, 1855). A. lusitanicus sensu Mabille, on the contrary, is restricted to Portugal (Quinteiro et al., 2005). In addition, there is no evidence to suggest that A. vulgaris occurs on the Iberian Peninsula outside the southern Pyrenees of Catalunya (Chevallier, 1981; Castillejo, 1998; Quinteiro et al., 2005). Theories for its area of origin range from southern Europe (Schmid, 1970) to the Alpine Region. Chevallier (1981) gives a map showing its French range, which is mainly Pyrenean rather than alpine.
Arion vulgaris has been spread by international trade from central and south France and can now be found throughout much of central, northern and eastern Europe. In many regions, it is well-established and has partly replaced the native large arionids: A. rufus and A. ater, especially in anthropogenic habitats, to become a serious pest (Fechter and Falkner, 1990; Turner et al., 1998). There has been considerable interbreeding with rufus and ater throughout its range (Zemanova et al., 2017) and the resulting vigorous hybrids may contribute to notable local increases in numbers. A. vulgaris appears uncommon at higher altitudes, at least in the Alps (ca. 1600 m above sea level; Turner et al., 1998) although this may not apply to the Pyrenees (Chevallier, 1981). Often, there is a clear gradation from pure A. vulgaris in valleys, through hybrids on the slopes, to A. rufus at higher altitudes in European mountains, paralleling ecological gradients (Zemanova et al., 2017).
Extensions in its range have been recorded in a number of countries since 2000. It is now confirmed from Ireland (Anderson, 2010), where it was earlier confused with other taxa. Similarly, it has been identified in the UK mainland, occurring sporadically in disturbed habitats of SE England (Davies, 1987). More recently (2015), it has been cited as especially numerous from localities around Norwich (JIC, 2021). It has recently been found in Iceland for the first time (Ingimarsdóttir and Ólafsson, 2005). Outside Europe, there is a suspected occurrence in the Falkland Islands (Proschwitz, 1988). This report has not been confirmed because the specimen involved was badly damaged. There is also a single unconfirmed report from Cornell University in the USA from October 1998.
Distribution TableTop of page
The distribution in this summary table is based on all the information available. When several references are cited, they may give conflicting information on the status. Further details may be available for individual references in the Distribution Table Details section which can be selected by going to Generate Report.Last updated: 17 Dec 2021
|Continent/Country/Region||Distribution||Last Reported||Origin||First Reported||Invasive||Reference||Notes|
|Bulgaria||Present, Localized||Introduced||Invasive||Synanthropic; Stara Planina only|
|Faroe Islands||Present, Widespread||Introduced||1996||Invasive|
|Finland||Present, Localized||Introduced||Invasive||Aland Isles|
|France||Present, Widespread||Native||Invasive||Described from near Lyons in 1855, now widespread|
|Iceland||Present, Localized||Introduced||2003||Invasive||South only; Original citation: Ingimarsdóttir and Ólafsson (2005)|
|Italy||Present, Localized||Introduced||Invasive||North only|
|Norway||Present, Localized||Introduced||1988||Invasive||Coastal; south and west|
|Poland||Present, Widespread||Introduced||1987||Invasive||Original citation: Koz
|-Azores||Present, Widespread||Unclear whether the taxon referred to here is vulgaris or lusitanicus s.s.|
|Spain||Present, Localized||Native||Catalunya only|
|United Kingdom||Present, Widespread||Introduced||1954||Invasive||Locally abundant at many sites, but especially common in the south east|
History of Introduction and SpreadTop of page
Arion vulgaris was first recognized in the UK and France in the early 1950s (Winter, 1989; Kerney, 1999), but has spread extensively throughout the SE of the UK (Davies, 1987; Rowson et al., 2014; JIC, 2021). It was first reported in Switzerland in 1955 (Turner et al., 1998), where it has been shown to hybridize with endemic A. rufus; these vigorous and adaptable forms (Knop and Reusser, 2012) are spreading rapidly in Alpine areas (Zemanova et al., 2017) and possibly throughout the range of A. vulgaris, displacing native large Arions. It was first reported in Germany in 1965 (Schmid, 1970), in Belgium in 1974 (Winter, 1989), in the Netherlands in 1988 (Winter, 1989) and in Austria in 1972 (Fischer and Reischütz, 1998). Before German unification in 1990, A. vulgaris was well-established in West, but not in East Germany (Proschwitz, 1997b). The first record for the former East Germany is from 1994 (Proschwitz, 1997b). In Sweden, A. vulgaris was first recorded in 1975, but from 1987 onwards populations exploded and the species spread rapidly to new sites. Of all the records in Sweden, 99% are from anthropogenic and only 1% from natural woodlands (Proschwitz, 1997a).
Outside Europe, there is a suspected occurrence in the Falkland Islands (Proschwitz, 1988). This report has not been confirmed because the specimen involved was badly damaged. There is also an unconfirmed report from Cornell University in the USA from October 1998.
In addition to the information provided in the History of Introduction table, A. vulgaris has been confirmed from Ireland. Kerney (1999), in his atlas of non-marine Mollusca, shows A. lusitanicus (=vulgaris) as an Irish species. However, subsequent research indicates that Kerney’s records are probably in error. The species has since been unequivocally recorded in Ireland by Anderson (2010).
IntroductionsTop of page
|Introduced to||Introduced from||Year||Reason||Introduced by||Established in wild through||References||Notes|
|Natural reproduction||Continuous restocking|
|Austria||1972||Yes||No||Fischer and Reischütz (1998)||Accidental|
|Belgium||1974||Yes||No||De Winter (1989)||Accidental|
|Bulgaria||Yes||No||Wiktor (1983)||Accidental; in Stara Planina|
|Czech Republic||1993||Yes||No||Dvorák and Horsák (2003)||Accidental|
|Denmark||1991||Yes||No||Proschwitz and Winge (1994)||Accidental|
|Falkland Islands||UK||No||No||Proschwitz (1988)||Accidental. In Port Stanley|
|Faroe Islands||Denmark||1996||Yes||No||Weidema (2006)||Accidental|
|Finland||1990||Yes||No||Valovirta (1995)||Accidental; Aland Islands|
|Germany||Yes||No||von Proschwitz (1997b)||Accidental|
|Iceland||2003||Yes||No||Ingimarsdóttir and Ólafsson (2005)||Accidental|
|Netherlands||1988||Yes||No||De Winter (1989)||Accidental|
|Norway||1988||Yes||No||Proschwitz and Winge (1994)||Accidental|
|Poland||Yes||No||Kozlowski and Kornobis (1995)||Accidental|
|Slovakia||1992||Yes||No||Cejka et al. (2006)||Accidental|
|Spain||Yes||No||Chevallier (1981)||Accidental; Catalunya|
|Sweden||1975||Yes||No||Proschwitz (1997a)||Accidental; southern Sweden|
|Switzerland||1955||Yes||No||Turner et al. (1998)||Accidental|
|UK||Yes||No||Kerney (1999); Rowson et al. (2014)||Accidental|
Risk of IntroductionTop of page
It is likely that A. vulgaris will continue to spread northwards and especially eastwards in Europe, to the Baltic States and Russia (Proschwitz, 1997a). It is likely this range expansion will be facilitated by its frequent hybridization with local species of large Arion, allowing vulgaris to assimilate locally adaptive traits (Knop and Reusser, 2012; Zemanova et al., 2017). It may be expected to turn up eventually in the Antipodes and in North America.
A survey of introduced slugs in California, USA, categorizing taxa only by their ITS sequencing using identified UK material as standards, found only A. rufus (R McDonnell, UCLA, personal communication, 2008). But use of only limited numbers of molecular markers provides little power to determine if these animals are rufus or vulgaris-rufus hybrids.
Many authors refer to its propensity for transport with plant materials through the horticultural trade and the gardening trade, a characteristic facilitated by frequently high population densities.
HabitatTop of page
Arion vulgaris is most frequent in agricultural and horticultural habitats with permanent, dense vegetation, such as grassland, fallows and gardens and is often abundant in compost heaps (Dörler et al., 2018). In low numbers, it is present in most agricultural and horticultural land and also increasingly in natural habitats (Fechter and Falkner, 1990; Turner et al., 1998).
Habitat ListTop of page
|Terrestrial||Managed||Cultivated / agricultural land||Principal habitat||Harmful (pest or invasive)|
|Terrestrial||Managed||Protected agriculture (e.g. glasshouse production)||Secondary/tolerated habitat||Harmful (pest or invasive)|
|Terrestrial||Managed||Managed forests, plantations and orchards||Secondary/tolerated habitat||Harmful (pest or invasive)|
|Terrestrial||Managed||Disturbed areas||Principal habitat||Harmful (pest or invasive)|
|Terrestrial||Managed||Rail / roadsides||Principal habitat||Harmful (pest or invasive)|
|Terrestrial||Managed||Urban / peri-urban areas||Principal habitat||Harmful (pest or invasive)|
|Terrestrial||Natural / Semi-natural||Natural forests||Secondary/tolerated habitat||Harmful (pest or invasive)|
|Terrestrial||Natural / Semi-natural||Scrub / shrublands||Secondary/tolerated habitat||Harmful (pest or invasive)|
Hosts/Species AffectedTop of page
Arion vulgaris is a serious pest of diverse vegetable crops (especially Brassicaceae, lettuce, cucurbits), vegetable seedlings, arable crops (Triticeae), forage (helianthus), ornamental plants, low-growing fruits (strawberries) and herbs within gardens, regularly causing severe losses (Dörler et al., 2018). In the early stages of arable crop development (after seedling emergence or after planting), the plants are seriously defoliated or completely destroyed. The leaves, flowers or fruit may be damaged with feeding holes and the potential harvest devalued. In Austria, serious damage to arable agriculture has been reported (Reischütz, 1984). In Poland, A. vulgaris was found to feed on a wide range of plants, including arable crops and commonly occurring weeds. Significantly, vulgaris was found to destroy far more seeds in its gut than native gastropod species (Blattmann et al., 2013). Slug damage was found on 103 plant species (including wild species), preferred crops including Brassica napus (Kozlowski and Kaluski, 2004; Kozlowski, 2005).
Host Plants and Other Plants AffectedTop of page
Growth StagesTop of page
SymptomsTop of page
Copious deposits of slime and slime trails leading from damaged site indicate activity.
Damage only within 1-5 m from the field edge, next to an area with dense, undisturbed vegetation, for example, grassland, fallow, scrub and garden.
Surface damage to large plants or plant parts specifically indicates the presence of this species. Complete removal of plants above ground may occur.
No damage occurs below ground with this species.
List of Symptoms/SignsTop of page
|Fruit / external feeding|
|Fruit / frass visible|
|Fruit / reduced size|
|Inflorescence / external feeding|
|Leaves / external feeding|
|Leaves / frass visible|
|Leaves / shredding|
|Roots / external feeding|
|Seeds / external feeding|
|Stems / external feeding|
|Stems / visible frass|
|Vegetative organs / external feeding|
|Whole plant / external feeding|
|Whole plant / frass visible|
Biology and EcologyTop of page
Arion vulgaris shows comparatively little genetic variation through its central European range (Quinteiro et al., 2005). Material from Switzerland (Zemanova et al., 2017), Britain, France, Italy and Norway (Hatteland et al., 2015) shows genetic evidence of hybridization and introgression with A. ater and A. rufus. These observations are concordant with data on metabolic rates of individuals of these species from Sweden (Hagnell et al., 2003) which appear to suggest hybridization between A. vulgaris and A. rufus.
Interpretation of these data is complicated by the suggestion (Chevallier, 1981) that the A. ater complex in Europe comprises species additional to those presently recognized, i.e. A. ater, A. rufus and A. vulgaris.
Arion vulgaris has an annual life cycle (Davies, 1987). In the British Isles, mating takes place between late July and early September. Courtship starts after sunset and copulation may take between 2 and 3 h (Davies, 1987). The eggs are laid between September and November and the adults then die off. The juveniles appear in spring (March/April) and grow rapidly to maturity in June/July.
The life cycle is flexible, adapting to local conditions with two generations thought to occur in especially favourable (warm, moist) environments, with a biennial life cycle adopted in less favourable high altitude sites (Knop and Reusser, 2012).
Although A. vulgaris can self-fertilise, populations of A. vulgaris reproduce more often by outcrossing
Physiology and Phenology
Due to recent expansions in range, the difficulty in distinguishing A. vulgaris from related species and the possibility of widespread hybridization and introgression, few reliable observations on regional phenotypic variability are reported.
Chevallier (1977) noted a tendency for dark-coloured individuals to occur at higher altitudes in the species native range in France and for brighter, reddish-coloured individuals to predominate in warmer regions and at lower altitudes. Observations consistent with hybridization of local species such as A. ater and A. rufus in these locations (Zemanova et al., 2017), producing highly plastic and adaptable forms locally (Knop and Reusser, 2012).
ClimateTop of page
|Cf - Warm temperate climate, wet all year||Preferred||Warm average temp. > 10°C, Cold average temp. > 0°C, wet all year|
|Cs - Warm temperate climate with dry summer||Preferred||Warm average temp. > 10°C, Cold average temp. > 0°C, dry summers|
|Ds - Continental climate with dry summer||Tolerated||Continental climate with dry summer (Warm average temp. > 10°C, coldest month < 0°C, dry summers)|
|ET - Tundra climate||Tolerated||Tundra climate (Average temp. of warmest month < 10°C and > 0°C)|
Latitude/Altitude RangesTop of page
|Latitude North (°N)||Latitude South (°S)||Altitude Lower (m)||Altitude Upper (m)|
Natural enemiesTop of page
|Natural enemy||Type||Life stages||Specificity||References||Biological control in||Biological control on|
|Anas platyrhynchos||Predator||Adults; Nematodes|Juveniles||not specific|
|Carabus||Predator||Eggs; Nematodes|Juveniles||not specific||Hatteland et al. (2013)|
|Cychrus caraboides||Predator||Eggs; Nematodes|Juveniles||not specific|
|Erinaceus europaeus||Predator||Adults||not specific|
|Phasmarhabditis hermaphrodita||Parasite||Nematodes|Juveniles||not specific||Hatteland et al. (2013)|
|Pterostichus||Predator||Eggs; Nematodes|Juveniles||not specific|
|Silpha atrata||Predator||Adults; Nematodes|Juveniles||not specific|
Notes on Natural EnemiesTop of page
No natural enemies have yet been shown to substantially reduce the populations of A. vulgaris.
Means of Movement and DispersalTop of page
Very little is known about the rates of spread of this species. However, there is now evidence to suggest gradual spread and introgression with local species of large Arions in areas where A. vulgaris has become established (Zemanova et al., 2017).
An introduction to new areas is always accidental and appears to occur with the movement of plant materials including garden and horticultural waste.
Pathway CausesTop of page
Pathway VectorsTop of page
Impact SummaryTop of page
Economic ImpactTop of page
No overall assessment of the economic consequences of A. vulgaris has been made, but the species contributes to damage on several horticultural crops (Fischer and Reisschütz, 1998). Strawberry growers in Norway have reported more than 50% loss in yield due to A. vulgaris, but proper economic assessments have not been conducted yet (Weidema, 2006). Much of the uncertainty surrounding impact attributable to this species is a consequence of its confusion with endemic species with which it hybridizes.
Environmental ImpactTop of page
Impact on Habitats
Arion vulgaris can be a significant cause of defoliation of wild plants and even trees (Proschwitz, 1997a). However, these effects are likely to be short-lived and the severity of defoliation will be dependent upon a number of environmental variables controlling slug breeding success.
Impact on Biodiversity
The main impact on biodiversity noted by authors has been the decline in numbers and disappearance of Arion rufus in areas where A. vulgaris is abundant and invasive (Fischer and Reischütz, 1998). It is now clear that their apparent decline is due to hybridization with these local species (Hatteland et al., 2015; Zemanova et al., 2017).
Social ImpactTop of page
The use of toxic baits could have health impacts on children in gardens and on predators that may accumulate poisons. The volume of sales of garden slug killers in central Europe has been linked to the prevalence of this species (Weidema, 2006).
Risk and Impact FactorsTop of page
- Proved invasive outside its native range
- Abundant in its native range
- Highly adaptable to different environments
- Is a habitat generalist
- Tolerates, or benefits from, cultivation, browsing pressure, mutilation, fire etc
- Pioneering in disturbed areas
- Capable of securing and ingesting a wide range of food
- Benefits from human association (i.e. it is a human commensal)
- Fast growing
- Has high reproductive potential
- Reproduces asexually
- Changed gene pool/ selective loss of genotypes
- Negatively impacts agriculture
- Negatively impacts livelihoods
- Threat to/ loss of native species
- Competition - monopolizing resources
- Interaction with other invasive species
- Highly likely to be transported internationally accidentally
- Difficult to identify/detect in the field
- Difficult/costly to control
Uses ListTop of page
- Laboratory use
- Research model
Detection and InspectionTop of page
The occurrence of A. vulgaris in transported plant materials may involve the adults, juveniles or eggs.
The adults and juveniles are active after dark and may be detected in the evening or early morning, or by inspecting plant materials stored under cover. Like Deroceras reticulatum, all stages hide under debris, stones and wood and occasionally in the soil around root systems. Smaller stages may hide in leaf whorls.
The eggs are deposited on the soil, under dead leaves or other surface debris and are not buried in the soil.
Traps containing molluscicides (metaldehyde, carbamate, iron pyrophosphate hydrate) may be used to collect material, but hand collecting is often as efficient and avoids the risk of contaminating produce.
Similarities to Other Species/ConditionsTop of page
Arion vulgaris belongs to a clade of large round-back slugs inhabiting central, western and southern Europe. These include A. rufus, which has been dispersed with trade to western North America. A. vulgaris and A. rufus are closely related and able to hybridize (Hagnell et al., 2003, Hatteland et al., 2015; Zemanova et al., 2017).
Unfortunately, it is very difficult to distinguish between these species based on external morphology. Reliable methods of discrimination include: dissection of the distal genitalia in mature individuals (Noble 1992; Hatteland et al., 2015); the use of ITS1 sequencing data based on known reference material and microsatellite markers (Zemanova et al., 2017). The spermatophores exchanged during sexual intercourse are highly diagnostic, but they are unlikely to be available routinely. A summary of the internal and external characteristics of A. vulgaris are given by Davies (1987). Quick (1960) provides a useful summary for A. rufus.
Colour phases are often difficult to attribute to this species due to its frequent hybridization and introgression with endemic species: a dark phase and a light phase, are recognized but are most likely a consequence of introgression.
The dark phase (red-brown, black body colours) of A. vulgaris has a sub-dermal black pigment masked by an overlying reddish pigment. That the red pigment responds to environmental conditions and varies from bright red-brown (warm, dry conditions) to dark-brown or black (cold conditions) (Chevallier, 1977) is likely a consequence of introgression with local species, corresponding with the distribution of either A. rufus (warmer drier conditions) and A. ater (cooler wetter conditions). Colour can alter within a generation if specimens are transplanted from warm to cold areas, e.g. an increase in altitude or movement further north (R Anderson, [address available from CABI], personal communication, 2008). The foot fringe colour matches the overall body colour in the dark phase. In the dark phase of A. rufus, there is no indication of contrasting pigment layers in the dermis. In addition, the foot fringe is brighter, yellow or red to orange, usually contrasting markedly with (duller) body colours that may include grey or pure black.
The pale phase of A. vulgaris (yellowish to pale-brown body colours) lacks the contrasting dark subdermal pigment and the skin layers are uniform in colour. The pale phase is difficult to distinguish from A. rufus although the latter still tends to have brighter red to orange, contrasting foot fringes, whereas in A. vulgaris the foot fringe and body colours match better.
Populations of A. vulgaris reproduce more often by outcrossing than by selfing, although this is still possible in the absence of mates. Together with other large Arions such as A. rufus and A. ater, which are facultatively self-fertile, often producing a proportion of each egg clutch by self-fertilization, A. vulgaris lies at the end of a continuum which runs from preferential to occasional facultative self-fertilization.
Resting individuals of A. rufusand A. ater, when stimulated by stroking the back firmly, may react by rolling the body from side to side while in the contracted position. This reaction is not characteristic of A. vulgaris, although individuals which are the product of introgression may show a similar response (see Davies, 1987).
Prevention and ControlTop of page
Due to the variable regulations around (de)registration of pesticides, your national list of registered pesticides or relevant authority should be consulted to determine which products are legally allowed for use in your country when considering chemical control. Pesticides should always be used in a lawful manner, consistent with the product's label.
Early Warning Systems
No warning system is available for A. vulgaris. However, in habitats that have been undisturbed for at least 2 years, A. vulgaris often occurs in high numbers and is likely to cause damage.
Ploughing and other methods of soil cultivation significantly reduce slug populations, and the removal of vegetation deprives A. vulgaris of shelters. In recent years the establishment of fallows has been encouraged in many European countries as part of government-subsidized set-aside programmes. Along with grassland, fallows and other undisturbed habitats are excellent habitats for A. vulgaris. In these habitats, A. vulgaris builds up large populations rapidly and migrates into adjacent crops, often completely destroying the nearest few metres of the field. Thus, crops sensitive to slug feeding should not be sown or planted next to undisturbed habitats and undisturbed habitats should not be created next to a slug sensitive crop.
The nematode Phasmarhabditis hermaphrodita (Rhabditidae) is a moderately effective biocontrol agent for many slug species (Wilson et al., 1993; Glen et al., 1996). Juvenile A. vulgaris are susceptible to P. hermaphrodita, but larger specimens are not (B Speiser, FiBL, Frick, Switzerland, unpublished data).
Chinese ducks are successfully used to control slugs in horticultural crops (B Grimm, Institute of Zoology, Graz, Austria, personal communication; B Speiser, FiBL, Frick, Switzerland) but their use is limited by the labour requirement of herd management. If ducks swallow A. vulgaris, they need access to water to clean their beaks (Sulzberger, 1996). The successful use of ducks for control of snails is described by Sakovich (1996).
For chemical control of A. vulgaris, bait pellets are normally used. These contain either metaldehyde or a carbamate as active ingredient. The pellets are broadcast on the soil. If A. vulgaris migrates into the crop from an adjacent habitat, it may be sufficient to treat a narrow strip (0.5 m) with twice the dosage recommended for broadcast application (Friedli and Frank, 1998).
There is little scope to reduce damage by A. vulgaris through the use of resistant varieties.
Gaps in Knowledge/Research NeedsTop of page
Quantification of economic impacts is missing from almost all evaluations and should be followed up. An inherent difficulty with such quantification will be recognizing the impact of hybrids and introgressed endemic species, the activity of which is attributable to A. vulgaris.
The status of A. vulgaris in the USA is unclear. Apart from a uncorroborated report on the internet for Cornell University, USA in 1998 no evidence for its occurrence there has been adduced. Despite this, almost the whole of the continental USA falls within the latitudinal and climatic parameters suitable for this species. The relevant authorities are aware of the potential problem, but more studies addressing the identity of introduced large arionids in the USA are required. A molecular study in California, USA (R McDonnell, UCLA, personal communication, 2008) suggests that the invasive, large arionids in that area at least, are attributable to A. rufus; although using a single molecular marker cannot determine the level of hybridization and introgression in these introduced populations.
ReferencesTop of page
Altena CORvan, 1956. [English title not available]. (Notes sur les limaces, 3. (Avec la collaboration de Mm. Aten et A. Schouten) Sur la présence en France de'Arion lusitanicus Mabille) Journal de Conchyliologie, 95:89-99
Anderson R, 2010. The invasive pest slug Arion vulgaris Moquin-Tandon (=A. lusitanicus Mabille) (Mollusca: Arionidae) confirmed for Ireland, with an appeal for records. Irish Naturalists' Journal, 31(1):69-70. http://www.habitas.org.uk/inj/
Blattmann, T, Boch, S, Tuerke, M, Knop, E, 2013. Gastropod seed dispersal: an invasive slug destroys far more seeds in its gut than native gastropods. PLoS ONE, 8
Cesari P, 1978. [English title not available]. (Nota preliminare sulla diffusione in Italia e l'esplosione demografica nel Veneto di Arion lusitanicus Mabille) Lavori,Società veneziana di Scienze naturali., 3-7
Chevallier H, 1977. [English title not available]. (Observations sure le polymorphisme des limaces rouges (Arion rufus Linné et Arion lusitanicus Mabille) et de l'escargot petit-gris (Helix aspersa Müller)) Haliotis, 6:41-48
Colomba M, Backeljau T, Gregorini A, Jordaens K, 2007. Chromosome numbers and chromosomal evolution in the land snail genus Arion (Gastropoda, Pulmonata). In: Proceedings of the World Congress of Malacology, Antwerp, Belgium, 15-20 July 2007, 40
Dörler, D., Kropf, M., Laaha, G., Zaller, J. G., 2018. Occurrence of the invasive Spanish slug in gardens: can a citizen science approach help deciphering underlying factors?. BMC Ecology, 18(23), (02 August 2018). https://link.springer.com/article/10.1186/s12898-018-0179-7
Fechter R, Falkner G, 1990. Weichtiere. München, Germany: Mosaik Verlag
Friedli J, Frank T, 1998. Reduced applications of metaldehyde pellets for reliable control of the slug pests Arion lusitanicus and Deroceras reticulatum in oilseed rape adjacent to sown wildflower strips. Journal of Applied Ecology, 35(4):504-513
Glen DM, Wilson MJ, Hughes L, Cargeeg P, Hajjar A, 1996. Exploring and exploiting the potential of the rhabditid nematode Phasmarhabditis hermaphrodita as a biocontrol agent for slugs. Slug & snail pests in agriculture. Proceedings of a Symposium, University of Kent, Canterbury, UK, 24-26 September 1996., 271-280
Hatteland, B. A., Haukeland, S., Roth, S., Brurberg, M. B., Vaughan, I. P., Symondson, W. O. C., 2013. Spatiotemporal analysis of predation by carabid beetles (Carabidae) on nematode infected and uninfected slugs in the field. PLoS ONE, 8(12), e82142. doi: 10.1371/journal.pone.0082142
Hatteland, B. A., Solhøy, T., Schander, C., Skage, M., Proschwitz, T. von, Noble, L. R., 2015. Introgression and differentiation of the invasive slug Arion vulgaris from native A. ater. Malacologia, 58(1/2), 303-321. http://www.bioone.org/loi/mala
JIC, 2021. Slugwatch. Norwich, UK: John Innes Centre.https://www.jic.ac.uk/research-impact/technology-research-platforms/entomology-and-insectary/slugwatch/
Kerney MP, Cameron RAD, Jungbluth JH, 1979. Die Landschnecken Nord- und Mitteleuropas. Hamburg, Germany: Paul Parey
Knop, E., Reusser, N., 2012. Jack-of-all-trades: phenotypic plasticity facilitates the invasion of an alien slug species. Proceedings of the Royal Society B. Biological Sciences, 279(1747), 4668-4676. doi: 10.1098/rspb.2012.1564
Kozlowski J, Kaluski T, 2004. Preferences of Deroceras reticulatum (O. Müller), Arion lusitanicus Mabille and Arion rufus (Linnaeus) for various weed and herb species and winter oilseed rape (II group plants). Folia Malacologica, 12:173-180
Kozlowski J, Kornobis S, 1995. [English title not available]. (Arion lusitanicus Mabille, 1868 (Gastropoda: Arionidae) w Polsce oraz nowe stanowisko Arion rufus (Linnaeus, 1758)) Przeglad Zoologiczny, 39:79-82
Kozłowski, J., 2007. The distribution, biology, population dynamics and harmfulness of Arion lusitanicus Mabille, 1868 (Gastropoda: Pulmonata: Arionidae) in Poland. Journal of Plant Protection Research, 47(3), 219-230. http://www.ior.poznan.pl/Journal/
Laznik Z, Ross JL, Trdan S, 2010. Massive occurrence and identification of the nematode Alloionema appendiculatum Schneider (Rhabditida: Alloionematidae) found in Arionidae slugs in Slovenia. Acta Agriculturae Slovenica, 95(1):43-49. http://aas.bf.uni-lj.si/februar2010/06laznik.pdf
Ludwig A, Reise H, Hutchinson JMC, 2015. The slug fauna of gardens in the town of Görlitz (Saxony, Germany). (Die Nacktschneckenfauna in Gärten der Stadt Görlitz (Sachsen, Deutschland).) Berichte der Naturforschenden Gesellschaft der Oberlausitz, 23:43-57. http://www.naturforschende-gesellschaft-der-oberlausitz.de/Publikationen
Pfenninger, M., Weigand, A., Bálint, M., Klussmann-Kolb, A., 2014. Misperceived invasion: the Lusitanian slug (Arion lusitanicus auct. non-Mabille or Arion vulgaris Moquin-Tandon 1855) is native to Central Europe. Evolutionary Applications, 7(6), 702-713. doi: 10.1111/eva.12177
Proschwitz, T. Von, 1997. Erstnachweis von Arion lusitanicus Mabille in Mecklenburg-Vorpommern. Schriften zur Malakozoologie, 10:21-22
Quinteiro J, Rodríguez-Castro J, Castillejo J, Iglesias-Piñeiro J, Rey-Méndez M, 2005. Phylogeny of slug species of the genus Arion: evidence of monophyly of Iberian endemics and of the existence of relict species in Pyrenean refuges. Journal of Zoological Systematics and Evolutionary Research, 43(2):139-148. http://www.blackwell-synergy.com/servlet/useragent?func=showIssues&code=jzs
Rowson, B, Anderson, R, Turner, JA, Symondson, WOC, 2014. The slugs of Britain and Ireland: undetected and undescribed species increase a well-studied, economically important fauna by more than 20%. PLoS ONE, 9(4), https://doi.org/10.1371/journal.pone.0091907
Sakovich NJ, 1996. An integrated pest management (IPM) approach to the control of the brown garden snail, (Helix aspersa) in California citrus orchards. In: Henderson IF, ed. Slug & Snail Pests in Agriculture. Farnham, UK: British Crop Protection Council, 283-287
Soroka M, Kaluski T, Kozlowski J, Wiktor A, 2007. Molecular diversity among populations of the terrestrial slugs Arion lusitanicus and Arion rufus (Mollusca, Pulmonata, Arionidae) in Poland. In: Proceedings of the World Congress of Malacology, Antwerp, Belgium, 15-20 July 2007, 211 pp
Sulzberger R, 1996. Wenn Schnecken zur Plage werden. München, Germany: BLV
Turner H, Kuiper JGJ, Thew N, Bernasconi R, Ruetschi J, Wuthrich M, Gosteli M, 1998. Atlas of the Mollusca of Switzerland and Liechtenstein. Atlas der Mollusken der Schweiz und Liechtensteins., 527 pp
Anderson R, 2010. The invasive pest slug Arion vulgaris Moquin-Tandon (=A. lusitanicus Mabille) (Mollusca: Arionidae) confirmed for Ireland, with an appeal for records. Irish Naturalists' Journal. 31 (1), 69-70. http://www.habitas.org.uk/inj/
CABI, Undated. Compendium record. Wallingford, UK: CABI
CABI, Undated a. CABI Compendium: Status as determined by CABI editor. Wallingford, UK: CABI
Cesari P, 1978. [English title not available]. (Nota preliminare sulla diffusione in Italia e l'esplosione demografica nel Veneto di Arion lusitanicus Mabille). Lavori, Società veneziana di Scienze naturali. 3-7.
Friedli J, Frank T, 1998. Reduced applications of metaldehyde pellets for reliable control of the slug pests Arion lusitanicus and Deroceras reticulatum in oilseed rape adjacent to sown wildflower strips. Journal of Applied Ecology. 35 (4), 504-513. DOI:10.1046/j.1365-2664.1998.3540504.x
Hagnell J, Schander C, Nilsson M, Ragnarsson J, Valstar H, Wollkopf A M, Proschwitz T von, 2006. How to trap a slug: commercial versus homemade slug traps. Crop Protection. 25 (3), 212-215. DOI:10.1016/j.cropro.2005.04.008
Kerney MP, Cameron RAD, Jungbluth JH, 1979. (Die Landschnecken Nord- und Mitteleuropas)., Hamburg, Germany: Paul Parey.
Laznik Ž, Ross J L, Trdan S, 2010. Massive occurrence and identification of the nematode Alloionema appendiculatum Schneider (Rhabditida: Alloionematidae) found in Arionidae slugs in Slovenia. Acta Agriculturae Slovenica. 95 (1), 43-49. http://aas.bf.uni-lj.si/februar2010/06laznik.pdf
Ludwig A, Reise H, Hutchinson J M C, 2015. The slug fauna of gardens in the town of Görlitz (Saxony, Germany). (Die Nacktschneckenfauna in Gärten der Stadt Görlitz (Sachsen, Deutschland).). Berichte der Naturforschenden Gesellschaft der Oberlausitz. 43-57. http://www.naturforschende-gesellschaft-der-oberlausitz.de/Publikationen
Moquin-Tandon A, 1855. Histoire naturelle des mollusques terrestres et fluviatiles de la France contenant des études générales sur leur anatomie et leur physiologie et la description particulière des genres, des esp. Paris, France: J. B. Baillière. 646 pp.
Rowson B, Anderson R, Turner JA, Symondson WOC, 2014. The slugs of Britain and Ireland: undetected and undescribed species increase a well-studied, economically important fauna by more than 20%. PLoS ONE. 9 (4), https://doi.org/10.1371/journal.pone.0091907
Seebens H, Blackburn T M, Dyer E E, Genovesi P, Hulme P E, Jeschke J M, Pagad S, Pyšek P, Winter M, Arianoutsou M, Bacher S, Blasius B, Brundu G, Capinha C, Celesti-Grapow L, Dawson W, Dullinger S, Fuentes N, Jäger H, Kartesz J, Kenis M, Kreft H, Kühn I, Lenzner B, Liebhold A, Mosena A (et al), 2017. No saturation in the accumulation of alien species worldwide. Nature Communications. 8 (2), 14435. http://www.nature.com/articles/ncomms14435
Slotsbo S, 2014. Nobanis invasive alien fact sheet: Arion lusitanicus. In: Nobanis invasive alien fact sheet: Arion lusitanicus, https://www.nobanis.org/globalassets/speciesinfo/a/arion-lusitanicus/arion_vulgaris1.pdf
Speiser B, Zaller J G, Neudecker A, 2001. Size-specific susceptibility of the pest slugs Deroceras reticulatum and Arion lusitanicus to the nematode biocontrol agent Phasmarhabditis hermaphrodita. BioControl. 46 (3), 311-320. DOI:10.1023/A:1011469730322
Turner H, Kuiper J G J, Thew N, Bernasconi R, Ruetschi J, Wuthrich M, Gosteli M, 1998. Atlas of the Mollusca of Switzerland and Liechtenstein. (Atlas der Mollusken der Schweiz und Liechtensteins.). In: Atlas der Mollusken der Schweiz und Liechtensteins. Neuchâtel, Switzerland: Centre Suisse de Cartographie de la Faune (CSCF). 527 pp.
Zemanova M A, Broennimann O, Guisan A, Knop E, Heckel G, 2018. Slimy invasion: climatic niche and current and future biogeography of Arion slug invaders. Diversity and Distributions. 24 (11), 1627-1640. https://onlinelibrary.wiley.com/doi/full/10.1111/ddi.12789
OrganizationsTop of page
ContributorsTop of page
07/04/2008 Updated by:
Roy Anderson, Consultant, UK
04/12/2019 Updated by:
Leslie R Noble, Nord University, Norway
Distribution MapsTop of page
Select a dataset
CABI Summary Records
Unsupported Web Browser:
One or more of the features that are needed to show you the maps functionality are not available in the web browser that you are using.
Please consider upgrading your browser to the latest version or installing a new browser.
More information about modern web browsers can be found at http://browsehappy.com/