occasional paper no. 20 an atlas of oxfordshire

Occasional Paper No. 20 AN ATLAS OF OXFORDSHIRE TERRESTRIAL MOLLUSCA S.J.GREGORY, Northmoor Trust and J.M.CAMPBELL Published by Oxfordshire Museums in co-operation with the Northmoor Trust Oxfordshire Museums are a division of the Department of Leisure and Arts Oxfordshire County Council, Oxfordshire Museums Store, Witney Road, Standlake, Oxon, OX8 7QG Tel: 01865 300639 Oxfordshire County Council Oxfordshire Museums Service November 2000

Oxfordshire Museums Service – Biological Records Centre Atlas of Terrestrial Mollusca

CONTENTS Page Introduction 1 Recording: Past and Present 1 Habitat Associations 2 Oxfordshire Biological Records Centre 3 Acknowledgements 3 Bibliography 4 Introduction to the maps and species accounts 4 General Maps: Main Towns and Natural Areas 5 Calcareous Rocks 5 Woodlands 6 Tetrad Coverage 6 Species Maps (listed alphabetically by Genus, including recent synonyms): Page

Abida 15 Acanthinula 18 Acicula 7 Aegopinella 28 Arianta 50 Arion 21 Ashfordia 46 Azeca 10 Balea 42 Boettgerilla 34 Candidula 44 Carychium 8 Cecilioides 40 Cepaea 51 Cernuella 45 Clausilia 41 Cochlicopa 10 Cochlodina 40 Columella 12 Deroceras 37 Discus 20 Ena 19 Euconulus 39 Helicella 45 Helicigona 50 Helix 52

Page

Hygromia 48 Lauria 16 Lehmannia 36 Limax 34 Macrogastra 41 Malacolimax 36 Milax 32 Monacha 46 Nesovitrea 28 Oxychilus 29 Oxyloma 9 Perforatella 47 Pomatias 7 Punctum 20 Pupilla 16 Pyramidula 11 Succinea 9 Tandonia 33 Testacella 42 Trichia 48 Vallonia 17 Vertigo 13 Vitrea 27 Vitrina 26 Zenobiella 47 Zonitoides 31

Oxfordshire Museums Service – Biological Records Centre Atlas of Terrestrial Mollusca 1

INTRODUCTION The Mollusca are a large and diverse, group of mainly marine animals. Terrestrial snails and slugs belong to a small part of the Class Gastropoda. There is no real difference between a snail and a slug. In the latter the shell, so characteristic of snails, is merely reduced in size and usually internal. Most snails and slugs feed on lichens, algae, fungi or dead plant matter. Many will also scavenge corpses if encountered, but only a Glass Snail, Oxychilus draparnaudi, and the Shelled Slugs, Testacella spp., are active predators. These both feed primarily on earthworms. A few species, such as the Grey Field Slug, Deroceras reticulatum, and the Garden Snail, Helix aspersa, can be pests of crops and garden plants, but this is the exception. The Oxfordshire Molluscan fauna is not static. The majority of Oxfordshire’s 91 species of snail and slug live un-noticed in the countryside, many dependent on semi-natural habitats. As human activities put increasing pressure on the countryside some species have become amongst the county’s rarest inhabitants. Other species, such as the Garden Snail have been widely transported by human activities and have been spread well beyond their natural range. This process continues today and recent colonists of the county include the Greenhouse Slug, Lehmannia valentiana, which has now been found outdoors at a few garden centres. RECORDING: PAST AND PRESENT The terrestrial Mollusca are one of the most well worked invertebrate groups within Oxfordshire. The visual attractiveness and wide range of colour varieties exhibited by many species made them popular with Victorian collectors. During the 19th century numerous local lists were published, mainly for the Henley, Banbury and Oxford districts. Towards the end of the century these were collated by Collinge (1891) to give the first full county list complete with details of distribution. The 64 species included most of the county’s known rarities. In the 1920’s much work was undertaken by two emminent conchologists: the Rev. L.W.Grensted and A.E.Ellis. Four species were added to the county list: the elusive snails Vertigo substriata and V. moulinsiana and the slugs Arion intermedius and Malacolimax tenellus. Four additional species were added through taxonomic splitting of species aggregates. For example, Vallonia costata and V. excentrica were distinguished from V. pulchella. Similarly, Candidula gigaxii and Trichia plebeia were also added. This period cumulated with the publication of the Victoria County History of Oxfordshire (VCH) (Grensted 1938) with records collated for 72 species. Fieldwork undertaken by the Bureau of Animal Population Studies, based at Oxford University, generated many species records from the 1930’s onwards (the ’Wytham Survey’). Further taxonomic splits added Carychium tridentatum, Cochlicopa lubricella, and Vitrea contracta. In the 1960’s and 1970's Dr H.J.M.Bowen undertook surveys on local nature reserves. Largely neglected since the turn of the century, the early 1980’s generated many slug records, including those of M.R.Hughes. The slugs Arion fasciatus, A. silvaticus and Deroceras panormitanum (caruanae) are recorded for the first time. Since the late 1980's there has been a concerted effort by Dr A.I.Spriggs and the authors to achieve a balanced recording effort across the county within all habitats, including man-made


(synanthropic) sites, such as churchyards. The presence of five additional snails, Columella aspersa, Euconulus alderi, Perforatella subrufescens, Perforatella rubiginosa and most recently, Hygromia cinctella has been confirmed in the county. Six slugs, all strongly associated with man-made habitats, have also been discovered: Arion lusitanicus, A. flagellus, A. distinctus, Tandonia budapestensis, Boettgerilla pallens and Lehmannia valentiana. To date 91 species have been recorded from Oxfordshire. To the end of October 2000, over 20,000 site-based species records are held on the Oxfordshire Biological Records Centre (OBRC) computerised database (using RECORDER). The majority of these records are post 1990. The collection of data is ongoing. HABITAT ASSOCIATIONS Snails tend to be much more numerous on lime-rich soils, due to the requirement of lime for shell building. Slugs are not so dependent on lime and sites with acidic soils can be important for slugs, despite supporting a limited snail fauna. Some species, such as Desmoulin’s Whorl Snail (Vertigo moulinsiana) or the Ash-black Slug (Limax cinereoniger), have precise habitat requirements, which makes them good indicators of undisturbed semi-natural habitats. Unfortunately this also makes such species vulnerable to habitat change and degradation. As increasing pressure is put on the countryside for farming, forestry, housing and new roads these have become some of the county’s rarest inhabitants. Deciduous woodland: This is the natural climax vegetation of southern England and has proved the most diverse of the semi-natural habitats. Within Oxfordshire, well over 40 species are regularly encountered within semi-natural ancient deciduous woodland, especially where these lie over lime-rich soils, hold plenty of dead wood and support waterlogged (flushed) areas. Six species, Acicula fusca, Vertigo substriata (wet areas), Ena montana, Limax cinereoniger, Malacolimax tenellus and Perforatella subrufescens are confined to such prime habitat. Other typical woodland inhabitants are Azeca goodalli, Cochlodina laminata, Macrogastra rolphii and to a lesser extent the slugs Limax maximus and Lehmannia marginata. Calcareous fen and riverside marsh: Wetland is another important semi-natural habitat for slugs and snails within the county, provided they are not cut for hay or too heavily grazed. About 40 species are frequently encountered. Characteristic species include Succinea putris, Oxyloma pfeifferi, Vallonia pulchella, Zonitoides nitidus, Deroceras laeve, Euconulus alderi and Ashfordia granulata. Undisturbed wetland, with intact hydrology, is important for the locally scarce Whorl Snails Vertigo antivertigo, V. substriata (if shaded), and V. moulinsiana and the nationally rare Perforatella rubiginosa. Calcareous Grassland: The lime-rich, free draining soils favour snails that are adapted to the generally dry conditions. Herb-rich short turf grassland supports a specialist snail community characterised by Pupilla muscorum and the common Vallonia excentrica. Two declining species, Abida secale and Helicella itala are confined to such habitat. Helicigona lapicida, once widespread, is now extinct at its known grassland sites. More frequent species, such as Vertigo pygmaea, Candidula intersecta and C. gigaxii, will also inhabit rougher areas. Where there is a good mosaic of grazed short turf, rough grass and scrub up to 40 species can be


collected. Open scrub is important for two species, Pomatias elegans and the uncommon Roman Snail Helix pomatia. Limestone Walls: To a snail, these are nothing more than a poorly vegetated grassland and tend to support similar species. None-the-less old limestone walls, especially if mossy, hold a distinctive fauna. This is characterised by Pyramidula rupestris, Lauria cylindracea. Less frequently, the Tree Snail Balea perversa and the rarities Vertigo pusilla and Helicigona lapicida may be found. A similar species assemblage occurs on roofs tiled with ‘Cotswold slate’ limestone. Churchyards and Gardens: Man-made (synanthropic) habitats, even in urban areas, can be as diverse as many semi-natural sites. Such sites not only hold a wide range of the more generalist woodland and grassland species, but also a great variety of non-native species, accidentally introduced by human activity. Commonly encountered species include the snails Trichia striolata and Helix aspersa and the slugs Arion ater, A. distinctus, A. hortensis, Tandonia budapestensis and Deroceras panormitanum. Specialist ‘synanthropic’ species, rarely found away from built up areas, are the slugs Arion lusitanicus, A. flagellus, Milax gagates, Tandonia sowerbyi, Boettgerilla pallens, Limax flavus, Lehmannia valentiana, Testacella haliotidea and the carnivorous snail Oxychilus draparnaudi. Because of open public access churchyards have featured prominently in the synanthropic sites examined. OXFORDSHIRE BIOLOGICAL RECORDS CENTRE The Oxfordshire Biological Records Centre (OBRC) was set up in 1976 by the County Council Department of Museums Service and co-ordinates biological recording within the current administrative county of Oxfordshire. This was created during the local government reorganisation of 1974 by the amalgamation of ‘old’ Oxfordshire (vice-county 23) with the north-west part of Berkshire (vc 22). The uses of the OBRC are manifold and include planning, conservation, education and research. Details about the OBRC. and an annual newsletter are available to interested persons at the following address: John Campbell Oxon BRC Oxon County Museums Store, Witney Road, Standlake, Oxon, OX8 7QG ACKNOWLEDGEMENTS Dr Arthur Spriggs has been a major driving force behind this project, having undertaken much of the fieldwork, offered much advice on fieldwork techniques and provided useful comments on the draft text. Thanks are due to Miss Stella Davies (slugs) and Dr Michael Kerney (snails), of the Conchological Society of Great Britain and Ireland, for advice and prompt identification of difficult or unusual specimens. Mr Charles Elton kindly made the data in the


Wytham Survey available. Others recorders, notably Dr Keith Alexander, Dr Humphrey Bowen, M.R.Hughes and M.Weideli have contributed their Oxfordshire records to the OBRC. BIBLIOGRAPHY Collinge, W.E. (1891) The Land and Freshwater Mollusca of Oxfordshire. The Conchologist,

1: 11-53. Ellis, A.E. (1927) Additional notes on the Mollusca of the Oxford District. Journal of

Conchology. 18: 137-138. Grensted. L.W. (1926) Mollusca. In: Walker J.J. (Ed) The Natural History of the Oxford

District. Oxford University Press Grensted. L.W. (1938) Mollusca. In: Salzman L.P. (Ed) Victoria County History of

Oxfordshire, Oxford University Press. Kerney, M. (1999) Atlas of the Land and Freshwater Molluscs of Britain and Ireland. Harley

Books. Kerney, M. & Stubbs, A. (1980) The Conservation of Snails, Slugs and Freshwater Mussels.

NCC Whiteaves, J.F. (1857) On the Land and Freshwater Mollusca inhabiting the Neighbourhood

of Oxford. Ashmolean Society, Oxford. INTRODUCTION TO THE MAPS AND SPECIES ACCOUNTS The species maps have been produced from the computerised data-base held at the O.B.R.C. Species records are site based but the maps indicate the occurrence of a given species within tetrads. Tetrads are 2km by 2km areas defined by the even numbered national grid lines shown on Ordnance Survey maps. The 10km grid squares are shown as numbered solid lines with the tetrads between. Also shown is the course of the River Thames which is the approximate pre-1974 county boundary between Oxfordshire (vc.23) and Berkshire (vc.22). The maps illustrate the occurrence of all native and naturalised species, capable of surviving outdoors. Records are shown for live specimens falling into two time categories. Dead shells of unknown age are listed separately. Only the most recent record for a given tetrad is shown using the symbols below: Records made in or after 1985 Records made prior to 1985 only X Dead and sub-fossil shells of unknown age Species names follow those used in Kerney (1999), but recent name changes have been put in parentheses to avoid confusion. The presence of each species within the two vice-counties is indicated above the species account. Nationally Notable species (i.e. occurring in 16-100 10km grid squares throughout the British Isles) and those listed in the British Red Data Book (which documents rare and vulnerable species) or in the UK Biodiversity Action Plan (BAP) (which lists species with globally important populations occurring within Britain), are also noted. Species accounts refer to observations in Oxfordshire, unless noted otherwise. VCH refers to the Victoria County History (Grensted 1938). Each species account is followed by a brief summary of the British status.


MAIN TOWNS and NATURAL AREAS

��

��

��

��

��

��

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

44

River Thames

63

63

Thame

Oxford City

Bicester

55

64

6579

Banbury

Witney

ChippingNorton

Henley

Natural Areas are biogeographic zones characterised by physical factors such as geology and topography and provide a framework for conservation initiatives across England. Each has a unique landscape, rural land use and associated fauna and flora. Six Natural Areas, which clearly correspond to underlying geology (see Map below), occur in Oxfordshire. These are: 44: Midland Clay Vales 55: Cotswolds 63: Thames and Avon Vales 64: Midvale Ridge (‘Oxford Heights’) 65: Chilterns 79: Berkshire and Marlborough Downs

CALCAREOUS ROCKS

��

��

��

��

��

��

��

��

��

��

��

��

��

��

��

��

20 30 40 50 60 70 80

50

40

30

20

10

SP

00

SU

90

80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

ClayCap

Oolites, etc

Corallian

Chalk

The shaded areas indicate where limestones and chalk outcrop. These correspond closely to the Natural Areas of the Cotswolds, the Midvale Ridge and the Chilterns. Areas where this geology has been masked by more recent drift deposits (e.g. the Chiltern Clay Cap) have been omitted. Outcrops of clays occur elsewhere: Lower Lias to the north and bands of Oxford, Kimmeridge and Gault clays across the Clay Vales.


WOODLANDS

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 TETRAD COVERAGE

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

All tetrads containing one or more woodlands of more than 8 ha in area are shown. The approximate extent of woodland cover within each tetrad is indicated by the size of the symbol. The type and quality of the woodland varies considerably from conifer plantation to blocks of ancient deciduous forest. The well-wooded Chilterns are apparent. Other well-wooded areas occur on the Midvale Ridge and in the Cotswolds. The Clay Vales and the Berkshire Downs are, as a rule, poorly wooded. The map shows the number of species recorded within each tetrad across Oxfordshire. Although some areas are better recorded than others it is none the less apparent that the richest areas correspond to the lime-rich and well-wooded areas of the Cotwolds, the Midvale Ridge and the Chiltern escarpment.


POMATIIDAE Pomatias elegans (Müller 1774) - Round-mouthed Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 This distinctive burrowing snail can be locally common where lime-rich friable soils occur over chalk and limestones. The species is very gregarious with colonies (often indicated by abundant dead shells) typically found in semi-natural habitats, such as steep woods or scrubby grasslands. Described in the VCH as “common in calcareous districts”. It is locally common wherever friable lime-rich soils occur in southern England.

ACICULIDAE Acicula fusca (Montagu 1803) - Point Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

sub-fossilpre-1985post-1985

vc.22 & vc.23 Notable b. This small elusive snail inhabits ancient deciduous woodland where it can be found amongst moss or leaf litter and under dead wood or stones. Although probably under-recorded it is genuinely scarce in the county. Most records (usually for single specimens) are from the Chiltern Hills but also from Wychwood Forest and scattered sites on the Midvale Ridge. First recorded from Stow Wood, near Oxford, in 1857, the VCH lists three sites. Nationally, a widespread, but scarce and declining species, strongly associated with ancient deciduous woodland.


ELLOBIIDAE Carychium minimum Müller 1774 - Herald Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 This small species is widespread in variety of habitats throughout the county, but is easily over-looked. In leaf litter, under stones and dead wood, beneath loose bark on logs and within tussocks it can be numerous. Described as “common and widely distributed” in the VCH, but this also includes records for C. tridentatum. It is common throughout the British Isles.

Carychium tridentatum (Risso 1826) - Slender Herald Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985

post-1985

vc.22 & vc.23 A common and widespread species found in similar locations to C. minimum. Indeed the two species are often found together. They are not distinguished in older records and C. tridentatum was first recorded in 1952 at Wytham Wood. Another common species throughout the British Isles.


SUCCINEIDAE Succinea putris (Linné 1758) - Large Amber Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 This, and the following species, can sometimes prove difficult to separate on external characters. S. putris is widespread and associated with marshy ground. It does occur at ground level, but is most conspicuous high up on marginal plants, such as Sweet Grass (Glyceria maxima), bordering rivers and canals. It may prove to be under-recorded in the Clay Vales because farmland ditches have not been adequately surveyed. Described as “generally distributed” in the VCH. Throughout southern Britain this is a common species in wetland habitats.

Oxyloma pfeifferi (Rossmässler 1835) - Pfeiffer’s Amber Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 Another widespread wetland species often found on vegetation in marshes or fens. Specimens have not been dissected and atypical specimens may have been confused with S.putris (or vice versa). First recorded at Cowley Marsh, Oxford, in 1853 and referred to as “general on marshy ground” in the VCH. There is a large proportion of older records, possibly reflecting past confusion with S. putris rather than a recent decline. Common in a wide variety of wetland habitats throughout the British Isles.


COCHLICOPIDAE Azeca goodalli (Férussacc 1821) - Three-toothed Moss Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 This distinctive snail shows a strong preference for ancient deciduous woodland on lime rich or acidic soils, but avoids the Clay Vales. It can be locally widespread, such as in the hanging woods of the Evenlode valley, but is rarely numerous. It occurs amongst moss and beneath stones or dead wood. Four sites are given in the VCH, the earliest from Headington Quarry, Oxford, in 1855. Outside Oxfordshire this local species is scattered across England and Wales, typically in wooded areas.

Cochlicopa lubrica (Müller 1774) - Slippery Moss Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 This is one of the most widely recorded species in Oxfordshire. It is very common under stones and dead wood, amongst moss and leaf-litter or within tussocks in most habitats. Described as “common and general” in the VCH, but this also includes records for C. lubricella. This species is equally abundant throughout much of Britain.


Cochlicopa lubricella (Porro 1838)

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 This species, though widespread, is much less common than C. lubrica. It is found mainly in woodlands, but also inhabits other places including churchyards. The two species often occur together. The older records do not distinguish between them and C. lubricella was first recorded in 1952 at Wytham Wood. Widespread in Britain but much more localised than C. lubrica.

PYRAMIDULIDAE Pyramidula rupestris (Draparnaud 1801) - Rock Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 This species can be extremely numerous beneath moss and stones on limestone walls and on roofs constructed from ‘Cotswold slate’. It is often abundant in the west of the county, but becomes scarcer towards the east. It is absent from chalk in south, except where limestone has been imported. This distribution mirrors that given in the VCH i.e. “mainly in oolite and coral rag areas”. This species has a patchy distribution in Britain, but is locally common where outcrops of limestone coincide with a suitably humid climate.


VERTIGINIDAE Columella edentula aggregate - Toothless Chrysalis Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 It is difficult to separate the two species of Columella in the field and the majority of records simply refer to the species aggregate. The VCH gives four sites and comments that it is “surprisingly rare in the county”. They are small and elusive snails and it is only in recent years that an attempt has been made to distinguish between them. Recent surveys have shown C. edentula to be much more widespread in the county than C. aspera (see maps below). This is in keeping with nation trends, as C. edentula is more frequent in lowland areas, whilst C. aspera is more characteristic of upland areas and tolerant of acidic soils.

Columella edentula (Draparnaud 1805)

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23: Widespread in a variety of damp habitats, including woodland and marsh. Usually amongst moss or leaf litter, but sometimes climbing low vegetation.

Columella aspera (Martens 1830)

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23: Apparently rare and confined to areas where acidic soils occur, notably the Chiltern Hills.


Vertigo pusilla Müller 1774 - Wall Whorl Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.23 only Notable b This tiny species is known from a few old shaded moss covered limestone walls in the Cotswolds, where it lives amongst loose stones and moss. Although, easily overlooked it is genuinely rare. The VCH lists four sites, including one at Woodeaton where it was found in 1857 and still persists today. It may have declined since the 19th century and has not been seen in the “Banbury area” since 1855. This widespread but uncommon species is associated with rocky limestone grassland and old walls, mainly in northern England.

Vertigo antivertigo (Draparnaud 1801) - Marsh Whorl Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 Another small and elusive snail, found amongst rush and sedge litter or moss, in fens and riverside marshes. It is certainly not common in the county but may be overlooked at some sites. The VCH gives a single location, near Weston-on-the-Green in 1857. This characteristic wetland species is frequent in Britain but is declining in lowland England.


Vertigo substriata (Jeffreys 1833) - Striated Whorl Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 This rare wetland species is confined to a few sites on the Midvale Ridge, notably in the Cothill area. It inhabits scrubby fen and wet woodland, where it occurs amongst moss and sedge litter. It is not listed in the VCH. A widespread species found throughout Britain but scarce and declining in the south-east.

Vertigo pygmaea (Draparnaud 1801) - Common Whorl Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 This is the only widespread Vertigo in county, but in common with the other species it is elusive and probably underrecorded. Often found in small numbers amongst moss and grass-litter, rarely under dead wood. It prefers un-shaded sites ranging from wet meadows (where it climbs vegetation in winter) to dry calcareous grassland. A few records are from churchyards. It is widely recorded in the VCH. Frequent in much of Britain and the only species of Vertigo not showing a marked national decline.


Vertigo moulinsiana (Dupuy 1849) - Des Moulins’ Whorl Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 RDB3 UKBAP (p) This county rarity is well known from a number of calcareous fens in the Cothill area, where it was first recorded in 1906. Recorded from besides the Thames at Radley in the 1920’s, but not seen subsequently (now a gravel pit). Recently it has been recorded from two Thames-side marshes further downstream. It is normally very elusive but climbs tall vegetation in autumn where it is more easily collected. It is not listed in the VCH. This rare species is known from fens and riverside marshes in southern England. It is scarce throughout Europe and legally protected.

CHONDRINIDAE Abida secale (Draparnaud 1801) - Large Chrysalis Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 Notable b This species remains frequent on the short turf chalk grassland of the Chiltern Hills, where it was described as “local” in the VCH. It is usually found amongst grass-litter or under stones, occasionally at woodland edges. There is an outlying population on Whitehorse Hill, but further searches of the Berkshire Downs have failed to find additional sites. The species has long disappeared from outlying sites on the Cotswold and Midvale Ridge limestones and seems to be declining in the Chilterns. An uncommon species restricted to a few chalk and limestone areas in southern England (where it is declining) and the Pennines.


PUPILLIDAE Pupilla muscorum (Linné 1758) - Moss Chrysalis Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 This small species is widespread in the county but is only common on the Chiltern chalk. It is typically found in semi-natural short-turf grassland, including those on prehistoric earthworks, where it occurs amongst grass-litter and under stones. Occasionally it can be found on old limestone walls, including a few within churchyards. Described as “common and general” in the VCH, it is possible that this snail has undergone a decline in recent years. A widespread species found on lime-rich soils throughout Britain, especially on the chalk and limestone in the south-east, but declining in some areas.

Lauria cylindracea (da Costa 1778) - Common Chrysalis Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985

post-1985

vc.22 & vc.23 In gardens and churchyards this common species can be numerous, especially on stone walls or even roofs. It can also be found under loose bark on trees, such as willow pollards, or less commonly amongst leaf-litter in grasslands, fens or woodlands on lime rich soils. Given as “common and general” in the VCH. Throughout the British Isles this is common in a variety of typically dry habitats.


VALLONIIDAE Vallonia costata (Müller 1774) - Ribbed Grass Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 This, the commonest Vallonia in Oxfordshire, is typically found in dry open locations, such as calcareous grassland, gardens and churchyards. It can be found amongst moss, under stones and dead wood and often on walls. The three species of Vallonia are not always separated in older records, but the VCH describes this species as “frequent about Oxford”. On the lime-rich soils of south-eastern England this is a common species.

Vallonia pulchella (Müller 1774) - Beautiful Grass Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 This can be a common snail on the Thames flood plain, as is apparent from map. It occurs amongst moss and within tussocks on damp meadows and dead shells can be often found among flood debris. It is local elsewhere in the county, mainly associated with river valleys. Some of the older records may refer to V. excentrica, as the two were not always separated. The VCH regarded this as “the least common of the three species”. In south-eastern England this is a frequent inhabitant of damp meadows and marshes.


Vallonia excentrica Sterki 1892 - Eccentric Grass Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985

post-1985

vc.22 & vc.23 A widespread species inhabiting similar dry sites to V. costata, but it is less frequently encountered. In calcareous grassland it is typically found with P. muscorum, but it also inhabits road verges and lawns. Recorded as “common about Oxford and probably general” in the VCH. Some of the older records for V. pulchella may refer to this species. Common throughout south-eastern England, especially on lime-rich soils.

Acanthinula aculeata (Müller 1774) - Prickly Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 This small, but very distinctive, snail is probably common in deciduous woodland and hedge-banks throughout much of the county. However, it is rather elusive and is typically well concealed amongst leaf-litter or within crevices on the underside of dead wood or stones. The VCH considered it “general but not common”. Throughout the British Isles this is a common species.


ENIDAE Ena montana (Draparnaud 1801) - Mountain Bulin

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

sub-fossilpre-1985post-1985

vc.23 only RDB3 UKBAP (c) This rare snail inhabits ancient deciduous woodlands on lime rich soils, often on stony slopes. Restricted colonies occur on the Chiltern escarpment (where it was widely recorded in the VCH) and the Evenlode catchment in the Cotswolds. In the latter area it was apparently overlooked until recent decades. It is normally very elusive, hiding amongst moss and leaf litter, but in wet weather it readily climbs smooth barked trees, such as beech or ash, and becomes highly visible. There is no evidence of a local decline. This is a nationally rare and declining ancient woodland species patchily distributed across southern England.

Ena obscura (Müller 1774) - Lesser Bulin

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985

post-1985

vc.22 & vc.23 This species can be found in small numbers within woodlands, shady gardens and churchyards on lime-rich soils throughout the county. It usually occurs amongst leaf-litter or under dead wood, but sometimes frequents old stone walls and like E .montana, will readily climb tree trunks in wet weather. Described in the VCH as “fairly common”. Outside Oxfordshire this species is common in shady habitats on lime-rich soils throughout England and Wales.


ENDODONITIDAE Punctum pygmaeum (Draparnaud 1801) - Dwarf Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985

post-1985

vc.22 & vc.23 This minute species has proved elusive and is probably underrecorded. It is certainly widespread in the county and found in a variety of habitats, such as woodlands, grasslands and churchyards. Typically found amongst moss and leaf litter or within tussocks. It is widely recorded in the VCH. A common species throughout the British Isles, especially in wooded areas.

Discus rotundatus (Müller 1774) - Rounded Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 Within Oxfordshire this is the most commonly recorded snail. It is readily found under stones and dead wood, often in large numbers, in almost every habitat. It should be present in all tetrads. The VCH describes it as “common and general”. This species is abundant and ubiquitous throughout Britain.


ARIONIDAE: Roundback Slugs Arion ater (Linné 1758) - Great Black Slug

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 Varying in colour from cream, orange, reddish, brown to jet black this is the largest of the roundback slugs. A familiar sight in many urban areas, normally lurking amongst stones and general debris, but following rain specimens can be conspicuous in the open. Although less frequent in rural areas woodlands and grasslands are also inhabited. Dissection has shown both forms, ‘A. ater’ and ‘A. rufus’ to occur in county, but their relative distributions are not known and all records have been combined. Recorded in the VCH as “abundant and general”. This species is common throughout the British Isles in a wide variety of habitats.

Arion lusitanicus Mabille 1868 - Lusitanian Slug

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.23 only A recent addition to the county list, discovered by chance in 1993 following dissection of an ‘A. ater’ specimen. It has been found beneath stones, and amongst debris, in a churchyard in the east of the county, where it is probably a modern accidental introduction. All specimens have been orange/brown in colour. It may be overlooked at other similar sites and some records for A. ater may actually refer to this species. Most old records for this species refer to A. flagellus. However, it has been shown to be frequent in south-western England, with isolated records, typically in gardens, occurring elsewhere.


Arion flagellus Collinge 1893 - Durham Slug

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.23 only This large slug was also added to the county list in 1993 and is probably another modern introduction into the county. Specimens are typically bluish-green in colour, but are only reliably separated from A. ater by dissection. The few records are all from churchyards. It is may prove to be under-recorded and may also be increasing its range across the county. Beyond Oxfordshire, this species is widespread, but is most common in western areas. Until recently it had been misidentified as A. lusitanicus.

Arion subfuscus (Draparnaud 1805) - Dusky Slug

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 Throughout the county this is a common species. It is most numerous in rural sites, such as woodlands and hedge banks, where it can is readily found under stones and dead wood. It also occurs in churchyards and gardens. Recorded as “plentiful and general” in the VCH. Throughout many habitats in Britain this is a common species.


Arion circumscriptus aggregate - Bourguignat’s Slug

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

vc.22 & vc.23 The map (left) includes all records for Arion circumscriptus, A. silvaticus and A. fasciatus. The three species can be difficult to separate in the field and prior to the 1980’s all records within Oxfordshire were given for the species aggregate. This is given as “common and general” in the VCH. The distribution of the individual species within the county remains poorly known as can be seen from the maps below.

Arion circumscriptus Johnston 1828

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

vc.22 & vc.23 This may prove to be the commonest of the three species within the county. Records are mainly from woodlands, but also meadows and churchyards. It is usually found under stones or dead wood. In lowland habitats throughout the British Isles this is a frequent species.


Arion silvaticus Lohmander 1937

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 This slug, with pale silvery flanks, is perhaps the easiest of the aggregate to identify in the field and consequently tends to be the more often noted. The majority of the records are from deciduous woodland and the mapped records strongly correspond with well-wooded areas, such as the Chiltern Hills and the Cotswolds. Throughout the British Isles this is a frequent slug inhabiting most habitats.

Arion fasciatus (Nilsson 1823)

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 Of the three species this seems to be the rarest within the county. Many of the records are from disturbed sites such as churchyards. About a third of the records have confirmed by dissection. It is frequent throughout northern England and Scotland, especially in disturbed sites, but less common in the south.


Arion hortensis aggregate - Garden Slug

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 The three species of the Arion hortensis aggregate are only reliably separable by dissection. The majority of records refer to the species aggregate. All records are included in the map (left). It occupies a wide range of habitats, including urban areas where it can be a pest. The VCH describes it as “common and general”. The few dissected specimens indicate the presence of two species, A. hortensis sensu stricto (form ‘R’) and A. distinctus (form ‘A’) within in the county (see maps below). Both seem to be equally widespread and are probably common throughout the county. Both remain seriously underrecorded.

Arion hortensis Férussac 1819 (form ‘R’)

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

Arion distinctus Mabille 1868 (form ‘A’),

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

Nationally A. distinctus is believed to be common across much of the British Isles, whereas A. hortensis sensu stricto is much more confined to southern counties.


Arion intermedius Normand 1852 - Hedgehog Slug

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985

post-1985

vc.22 & vc.23 This common species is most numerous in rough grassland, where it typically occurs amongst moss and grass litter or within tussocks. It is found in a variety of sites from churchyards and road verges to semi-natural meadows, chalk grassland and open woodland. It was not recorded until 1907 (Blenheim Park), but considered “numerous around Oxford” in the VCH. Nationally, a very common slug in a wide array of habitats.

VITRINIDAE Vitrina pellucida (Müller 1774) - Pellucid Glass Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 This is a common species throughout the county but living specimens are rarely encountered outside of the winter months. It occurs under stones and dead wood in variety of habitats from churchyards to semi-natural woodland. Recorded as “common and general” in the VCH. It is very common throughout the British Isles often in damp woodlands and grassland.


ZONITIDAE Vitrea crystallina (Müller 1774) - Crystal Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 A widespread and common species within the county. It is found amongst moss and leaf litter, under stones and dead wood or within tussocks in a wide array of rural and urban sites. Described as “common and general” in the VCH, but this also includes records for V. contracta. Throughout the British Isles this is common in a variety of damp sheltered places.

Vitrea contracta (Westerlund 1871) - Milky Crystal Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 Another widespread ssail found in a wide array of rural and urban sites. It often occurs with V. crystallina, especially in drier sites, such as chalk grassland, but it generally seems to be less frequent. The two species are not distinguished in older records. It is common throughout the British Isles but preferring drier sites such as calcareous grassland or screes.


Nesovitrea hammonis (Ström 1765) - Rayed Glass Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 Although common throughout the county it is never found in large numbers. It is more prevalent in damper sites such as woodland, wetlands and meadows, occasionally in shady churchyards. It can be found under dead wood, amongst moss or within tussocks. In the VCH it is widely recorded. It is common throughout the British Isles in marshes, damp grassland and woodland.

Aegopinella pura (Alder 1830) - Clear Glass Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 This species is common throughout the county, especially in well wooded areas. It can be found under stones and dead wood or amongst leaf litter in a wide range of, mainly rural, habitats. In the VCH it is noted as occurring “sparingly”. A common snail throughout the British Isles, typically in deciduous woodland.


Aegopinella nitidula (Draparnaud 1805) - Smooth Glass Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 A very common species. Although most often encountered amongst moss in woodlands or scrub it occurs in most habitats. It can be numerous at some sites and dead shells often abound. Given as “common and general” in the VCH. In woodlands, rough grass and disturbed sites throughout the British Isles it is very common.

Oxychilus draparnaudi (Beck 1837) - Draparnaud’s Glass Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985

post-1985

vc.22 & vc.23 Unusually for a snail, this species is carnivorous, feeding mainly on earthworms. A fairly recent colonist into the county, it was first recorded at the Oxford Botanic Gardens in 1926 and had become well established in Oxford gardens by 1935 (VCH). It has since increased substantially and is now widespread throughout the county. Typically it occurs under large stones or among debris in churchyards, gardens and scrubby waste ground, seldom far from houses. This ancient introduction is widely established and increasing across much of England, typically in gardens.


Oxychilus cellarius (Müller 1774) - Cellar Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985

post-1985

vc.22 & vc.23 A common species occurring in a wide range of habitats, including disturbed sites, under stones and dead wood or amongst moss and leaf litter. Listed as “common and general” in the VCH. Nationally a very common snail occurring throughout the British Isles.

Oxychilus alliarius (Miller 1822) - Garlic Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 This common species is widespread, but has a preference for more acidic sites, such as woodlands on the Chiltern clay cap or the Midvale sands, even in conifer plantations. It is found under stones and dead wood and when handled it emits a pungent smell of garlic. The VCH considered it to be “generally distributed but local”. Another very common species in Britain.


Oxychilus helveticus (Blum 1881) - Swiss Glass Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985

post-1985

vc.22 & vc.23 Although widespread and common across much of the county it is scarce in the Clay Vales and on the Lias clays in the north. It predominantly inhabits woodlands, usually under dead wood, but also in shady churchyards and damp places generally. It can emit a slight smell of garlic when provoked, but never as potent as O. alliarius. It is widely recorded in the VCH. Possibly an old introduction, but now locally common throughout England and Wales.

Zonitoides excavatus (Alder 1830) - Hollowed Glass Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 and vc.23 The only likely records held at the OBRC for this species, typical of wet acidic woodland, are from Bagley Wood (1922) and from a Chiltern beech wood (1984). It has not been refound at either site. The habitat at the Chiltern site seems unsuitable and may be erroneous. There is no reason to doubt the Bagley record, but its status in the county is uncertain. Outside Oxfordshire this species is locally common in wet acidic woodland, especially in western Britain.


Zonitoides nitidus (Müller 1774) - Shiny Glass Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 This widespread species is associated with wet habitats, such as marshes, and is common on much of the Thames flood plain. It can be found under dead wood, amongst moss and flood debris or within tussocks. Described as “well distributed and common” in the VCH. The large proportion of old records may indicate a decline in some parts of the county. It is common throughout most of England and Wales and tolerant of flooding.

MILACIDAE - Keeled Slugs Milax gagates (Draparnaud 1801) - Jet Slug

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 This is a rare slug in Oxfordshire and may be an ancient introduction. There are just two recent records, from under stones in a churchyard and in a large domestic garden. First recorded in 1891, there are several records listed in the VCH. However, it is possible that some may refer to T. budapestensis, as then unrecognised from Britain. Although locally common in the south-west, it is uncommon inland and typically found in gardens.


Tandonia sowerbyi (Férussac 1823) - Keeled Slug

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

vc.22 & vc.23 Typically for an introduced species this large slug inhabits disturbed sites, such as gardens and churchyards, and can be common in some urban areas. It is most easily found by turning large stones. The VCH describes it as “apparently increasing” but this may include records for T. budapestensis, as then unrecognised in the county. Throughout Britain this species is a frequent inhabitant of gardens.

Tandonia budapestensis (Hazay 1881) - Budapest Slug

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

vc.22 & vc.23 Although not recorded in the VCH, this modern introduction may have reached Oxfordshire early in the 20th century and may have been long confused with T. sowerbyi or M. gagates. Its presence in the county was not confirmed until 1988 and it is has proved to be the commonest of the Milacid slugs by far. Found under stones and general debris, typically in gardens and churchyards, but also in hedgerows, disturbed woodland and scrub. Accidentally introduced into Britain around the turn of the century, it is now common and increasing in many areas.


Boettgerilla pallens Simroth 1912 - Worm Slug

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985

post-1985

vc.22 & vc.23 First recorded in Britain in 1972, this introduced slug was first collected at Oxford in 1988. It is now well established in gardens, churchyards and scrubby waste ground throughout Oxfordshire. Its subterranean habits make it rather elusive and it is most easily found by turning very large stones, especially in the winter months. Known from a handful of sites during the 1970’s this species is now locally frequent in many parts of Britain and continues to increase.

LIMACIDAE - Keelback Slugs Limax maximus Linné 1758 - Leopard or Great Grey Slug

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 When fully grown this can be a large and attractively marked species. Although characteristic of woodland (it is particularly common in the well-wooded Chiltern Hills), it also inhabits waste places and gardens and will even enter houses. Usually found under dead wood, but in wet weather it will readily climbs tree trunks. Given as “common and general” in the VCH. It is common throughout the British Isles.


Limax cinereoniger Wolf 1803 - Ash-black Slug

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 This, Britain’s largest slug, is surprisingly adept at concealing itself within large pieces of dead wood. In the autumn it is much easier to find, often close to fungi. It is a characteristic inhabitant of ancient deciduous woodlands in the Chiltern Hills, often on acidic soils. Outlying populations near Oxford (known since the 1850’s) and in the west of the county (a recent discovery) suggest it may be awaiting discovery in other suitable (acidic) woodlands. Beyond Oxfordshire this ancient woodland species is widespread, but local and declining.

Limax flavus Linné 1758 - Yellow Slug

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 Although widely recorded this species is not encountered with any frequency. Typically found in churchyards or gardens, it can be found under large stones or within crevices on stone walls. Described as “common and general” in the VCH, it seems to have become less common in recent years. This may reflect the loss of its preferred habitat: cellars, kitchens and sculleries. Throughout much of Britain this remains a frequent species.


Malacolimax tenellus (Müller 1774) - Slender Slug

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.23 only Notable b. UKBAP (c) All records for this elusive slug are from ancient Beech woodland in the Chiltern Hills, often associated with L. cinereoniger. Mature specimens, found in autumn, are bright yellow and are characteristically found on the underside of fungi, nearby beneath dead wood or climbing adjacent Beech trunks. There is no evidence of a local decline and it may even be under-recorded. The VCH gives one site, Checkendon, where it still occurs. This is an uncommon and declining species associated with ancient woodlands, including Caledonian pine-forest.

Lehmannia marginata (Müller 1774) - Tree Slug

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 In well-wooded areas, such as the Chiltern Hills, this species can be locally common. Although strongly associated with deciduous woodlands, it also occurs in churchyards and gardens. Often found under stones and dead wood, but in damp weather, large numbers will readily climb tree trunks or walls, becoming very conspicuous. Listed as “general and common” in the VCH. It is common throughout much of Britain especially in the west.


Lehmannia valentiana (Férussac 1821) - Greenhouse Slug

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 This recent addition to the county list was first recorded from Oxford in 1993. It is presently known from three garden centres, where it is most likely introduced from plant nurseries. It is probably present at other sites, including gardens, where it may be confused with L. marginatus. This species has long been known from glasshouses in Britain but is becoming more frequently recorded outside in gardens and garden centres.

Deroceras laeve (Müller 1774) - Marsh Slug

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 This small slug is characteristic of marshy ground, such as beside rivers, in fens and wet glades in woodlands. It is usually fairly elusive, but can be found in small numbers amongst moss, under dead wood or within tussocks. In the VCH it is described as “scarce but in most districts”. Throughout the British Isles this is a very common wetland slug.


Deroceras reticulatum (Müller 1774) - Grey Field Slug

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 This ubiquitous species is the most commonly encountered slug in the county and may be found anywhere. It can be particularly numerous at disturbed sites and can be a severe pest in gardens and arable fields. It should occur in all tetrads. The VCH simply says “ubiquitous”. It is equally abundant and ubiquitous throughout the British Isles.

Deroceras panormitanum (Lessona & Pollonera 1882) (=D. caruanae) - Caruana’s Slug

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 First recorded at Oxford in 1984, this modern introduction was not known to the VCH. Today it is a fairly common slug throughout the county and possibly continues to increase. It is typically found under stones and amongst debris in disturbed sites, such as gardens, churchyards and waste-ground. Not known in Britain until 1931 this species is now widely established particularly in western areas.


EUCONULIDAE Euconulus fulvus (Müller 1774) - Tawny Glass Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 This has proved to be a fairly common snail, especially in the drier well wooded Chiltern Hills. It occurs in a wide variety of habitats, including woodlands, grassland and churchyards, usually amongst moss and leaf litter, within tussocks or under dead wood. It is described as “sparingly but generally distributed” in the VCH, but this also includes records for E. alderi. Indeed the two species were not differentiated within the county until the 1980’s and some of the pre-1985 records may refer to E. alderi. Throughout the British Isles this is a

common snail.

Euconulus alderi (Gray 1840)

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 This species is less common than E. fulvus, and prefers damper habitats, such as flood meadows, fens or wet woodlands. Searching amongst moss, leaf litter or within tussocks can be productive. It is apparently absent from the waterless Chiltern Hills and Berkshire Downs. None the less, the two species often occur together and were not distinguished in older records. It is also widespread throughout Britain, but is more local than E. fulvus.


FERUSSACIIDAE Cecilioides acicula (Müller 1774) - Blind Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 This small blind species is exclusively subterranean. It is often discovered by turning large stones in gardens, churchyards or grasslands on friable lime-rich soils. It is widespread, but elusive, and is certainly underrecorded. For example, dead shells in mole hills or flood debris are much more widely encountered than living specimens. It is widely recorded in the VCH. In the chalk and limestone areas of south-eastern England this is a common species but it becomes much scarcer to the north.

CLAUSILIIDAE: Door Snails Cochlodina laminata (Montagu 1803) - Plaited Door Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 This large species was considered very scarce in the past and had a disjunct distribution. The VCH notes it as “not common, except (Chiltern) Beech woods”. It genuinely seems to have become more widespread in the last century and is now locally common wherever woodlands occur on calcareous soils. It is easily found under dead wood, often with C. bidentata, and will readily climb tree trunks in wet weather. A locally common species in woodlands on calcareous soils throughout England and Wales.


Macrogastra rolphii (Turton 1826) - Rolph’s Door Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985

post-1985

vc.22 & vc.23 Notable b. First recorded at South Hinksey, near Oxford, in 1880 this species was considered extinct by the VCH. Some 70 years later (1951) it was rediscovered at the nearby Wytham Woods. Recent surveys have shown it to occur in several nearby ancient calcareous deciduous woodlands. Outlying colonies occur in the Evenlode Valley and on the Chiltern escarpment. It lives amongst moss and leaf-litter, occasionally beneath dead wood, but unlike C. laminata and C. bidentata it never climbs trees. This uncommon species is confined mainly to the south-east of England.

Clausilia bidentata (Ström 1765) - Common Door Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 Within Oxfordshire, this ubiquitous snail is one of the most frequently encountered species. In woodlands and hedgerows it can be extremely numerous, especially under dead wood, and during wet weather it readily climbs trees in large numbers. Given as “common and general” in the VCH. This species is abundant over much of England and Wales.


Balea perversa (Linné 1758) - Tree Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 A widespread but rarely encountered snail. It is usually found within crevices or amongst moss on tree trunks or old stone walls, but becomes elusive in dry weather. Old willow pollards or senescent elders are often favoured. Recent records from mossy 'Cotswold slate' roofs suggest it may be more widespread than previously thought. It is widely recorded in the VCH. This predominantly western species has declined in many areas as a result of air pollution, but is making a comeback in many areas. This may also be the case in Oxfordshire.

TESTACELLIDAE: Shelled Slugs Testacella maugei Férussac 1819 - Maugé’s Slug

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc 22 only This carnivorous slug is not listed in Collinge (1891) or the VCH, but there is an old record from Faringdon in 1905 held by the OBRC. There have been no subsequent records. It is a particularly elusive species and may have been overlooked, but it has not been seen in central England for several decades. Believed to be an introduction, this apparently rare slug was widely recorded across southern England in the early twentieth century, but all modern records are from south-western areas.


Testacella haliotidea Draparnaud 1801 - Shelled Slug

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 This elusive earthworm predator is most easily found in autumn by turning large stones or hand sorting soil in churchyards or mature gardens. Although probably underrecorded it does seem to be genuinely scarce. Described as “not at all uncommon” in Collinge (1891) and widely recorded in the VCH it seems to be much less common now, perhaps reflecting the decline in manured vegetable plots and increased use of garden chemicals. Records for this is apparently rare slug are widely scattered throughout England.

Testacella scutulum Sowerby 1821 - Shield Slug

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 There are old records for this species. Collinge (1891) cites a record from Oxford in 1887, but adds; “I am now inclined to think that these specimens were T. haliotidea”. There have been no reliable modern records for the county. Recently a few possible specimens have been examined, but the characters used to separate the two species seem unreliable and the identification of T. scutulum is tentative. The few recent records for this slug are widely scattered across England.


HELICIDAE Candidula intersecta (Poiret 1801) - Wrinkled Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 A widespread snail typical of dry grassland on lime rich soils and can be numerous on poorly vegetated areas in quarries. In dry weather it can prove very elusive, but tends to miraculously re-appear following rain. It was considered much scarcer in the past and is described as “very local” in the VCH. A common species on the English chalk and limestone, but becomes more scarce elsewhere.

Candidula gigaxii (Pfeiffer 1850)

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 This species is usually associated with C. intersecta but is perhaps more tolerant of rougher calcareous grasslands. The VCH considered this to be the commoner of the two species, but there are relatively few recent records. This may indicate a decline in the county or possible confusion between the two. This species is locally frequent in southern England especially on lime-rich soils.


Cernuella virgata (da Costa 1778) - Striped Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 A common banded snail found amongst dry grassland, often with Candidula species. Typical sites include road verges, churchyards and semi-natural grassland, usually on lime rich soils. Considered “abundant and general” in the VCH. The distribution of this common species follows outcrops of calcareous rock across England and most coastal areas.

Helicella itala (Linné 1758) - Heath Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

sub-fossilpre-1970

��

��

��

��

��

��

��

��

��

��

��

��

��

��

��

�� 1970-1985

post-1985

vc.22 & vc.23 This large and distinctive snail was widely recorded in the VCH and in subsequent years. In recent decades it has declined dramatically at many sites, especially in the Cotswolds, and there are relatively few recent records for live specimens (most easily found in the autumn). It is confined to species rich calcareous grassland (never heathland!) and the Chilterns and Berkshire Downs remain a stronghold. Several colonies occur on prehistoric earthworks and railway cuttings, often maintained by rabbit grazing. Nationally, inland populations of this species are declining, but coastal populations seem to be thriving.


Monacha cantiana (Montagu 1803) - Kentish Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 This is a possible nineteenth century colonist of the county. Certainly, in 1857 it was only known from Headington, Oxford. It steadily spread to become “abundant and general” across the county by 1938 (VCH). Today it is one of our commonest snails and can occur in large numbers in gardens and other disturbed sites. It also inhabits road verges and open grasslands, but seldom penetrates far into woodland. This ancient introduction is very common in much of southern England and continues to spread north-west.

Ashfordia granulata (Alder 1830) - Silky Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 UKBAP (c) A widespread but local species within the county. It inhabits wet sites, such as marshes and rough riverside meadows. It can be found amongst moss and dead vegetation, beneath dead wood or within tussocks. First recorded at Bullingdon Bog, Oxford, in 1857 and considered “rare” in the VCH. This species has a patchy distribution throughout Britain and can be locally frequent, but is virtually absent from mainland Europe.


Perforatella subrufescens (Miller 1822) - Brown Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 only The only confirmed Oxfordshire record for this snail is by Dr K.N.A.Alexander from an ancient deciduous woodland near Faringdon in 1995. It is quite likely to occur in other acidic woodlands in the west of the county. It is listed in the VCH as “very rare”, but these and other more recent records are believed to be unreliable and have not been mapped. In northern and western areas of Britain this is a frequent species of ancient deciduous woodlands, but declining or absent elsewhere.

Perforatella rubiginosa (Schmidt 1853)

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.23 only RDB2 At its only known Oxfordshire locality it is found within sedge tussocks and amongst flood debris on a Thames-side marsh. Here it occurs with two superficially similar species, Ashfordia granulata and Trichia hispida, which does not help detection. For this reason it may be overlooked elsewhere (confusion with Trichia plebeia is also likely), but other apparently suitable sites have been searched without success. This very rare species was only discovered in Britain in 1981 and is known from a handful of periodically flooded sites in the lower Thames Valley.


Hygromia cinctella (Draparnaud 1801) - Girdled Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.23 only This Mediterranean snail is the most recent colonist of the county. In May 2000 a single specimen was collected under stones in the grounds of a school at Oxford. The species may be present at other sites and, judging by national trends, may quickly spread to new areas. It has been known from south Devon since the 1950’s, but in recent years has colonised several counties in southern England, including Berkshire and Gloucestershire.

Trichia striolata (Pfeiffer 1828) - Strawberry Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 Within Oxfordshire this is second most widely recorded species. It is ubiquitous in all habitats and is readily found under stones, dead wood and amongst general debris. In disturbed sites, such as churchyards, it can occur in large numbers. It should occur in all tetrads. Given as “abundant and general” in the VCH. It is common throughout most of the British Isles.


Trichia plebeia (Draparnaud 1805) Although widely recorded from the county in past, the reliability of these records has recently been questioned. Known Oxfordshire specimens have been re-examined, but all have proved erroneous. The VCH notes that it “occurs with T. hispida” and many records, seem to be based on misidentification of that species. At one site specimens have proved to be Perforatella rubiginosa. In the English midlands T. plebeia is locally common and there are confirmed records in Northamptonshire, just north of the county, where it occupies moist and sheltered places. It is possible that the species may also occur in the north of Oxfordshire. In the absence of reliable records the species has not been mapped. Trichia hispida (Linné 1758) - Hairy Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 This common snail is most frequently encountered in damp habitats, such as meadows, woodlands and even churchyards, but also on dry calcareous grasslands. Typically it is found under stones and dead wood but also within tussocks. In the VCH it is described as “common and general”. A common species throughout most of the British Isles.


Arianta arbustorum (Linné 1758) - Copse Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 A fairly common species in many parts of the county. It frequents rough herbage in a variety of damp habitats, including gardens, but predominantly in woodlands and marsh. It is considered “general but in restricted colonies” by the VCH. This widespread species can be locally common in many areas of Britain.

Helicigona lapicida (Linné 1758) - Lapidary Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

sub-fossilpre-1970

��

��

��

��1970-1985post-1985

vc.23 only The VCH described this large and attractive snail as “common on the Chilterns” where it mainly inhabited Beech woodland. Outlying colonies occurred on limestone grasslands and quarries of the Cotswolds and the Midvale Ridge. By the 1980’s it had disappeared from all its old haunts, although sub-fossil shells could still be found. Two new sites were discovered in the 1990’s with live specimens on churchyard walls in the west and beside a sunken track in a Chiltern wood. Its future existence in the county is uncertain. This local species is declining in many parts of England.


Cepaea nemoralis (Linné 1758) - Brown Lipped Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 This is one of the commonest species within the county, frequenting rough herbage in a variety of habitats from gardens and churchyards to grassland and open woodland. It is regarded as “common and general” in the VCH. It is equally common throughout much of Britain.

Cepaea hortensis (Müller 1774) White Lipped Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 This species is often found with C. nemoralis but is somewhat more local. It has a rather patchy distribution and seems to become much more scarce in the north of the county. Although found in a variety of habitats, including gardens, it has a strong preference for damp woodlands and marsh. In the VCH it is considered “common and general” It is common throughout much of the British Isles.


Helix aspersa Müller 1774 - Garden Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

pre-1985post-1985

vc.22 & vc.23 Throughout the county this is a familiar species in gardens, and other disturbed sites, where it can occur in large numbers. It can also be found in most rural habitats, including a few woods, but is much less abundant. Simply described as “ubiquitous” in the VCH. An ancient introduction, this species is very common in much of southern England.

Helix pomatia Linné 1758 Roman or Edible Snail

50

40

30

20

10

SP

00

SU

90

80

20 30 40 50 60 70 80

2

8642

8642

8642

8642

8642

8642

8642

8642

2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8 2 4 6 8

casualpre-1985post-1985

vc.22 & vc.23 Notable b UKBAP (c) This, Britain’s largest snail, is very local in the county. It occurs on friable lime-rich soils, most notably on the Cotswold oolite, but also along the Chiltern escarpment. It favours open scrubby banks, such as railway cuttings and woodland edges. Temporary introductions may occur elsewhere, but these rarely persist for long. First recorded at Stonesfield in 1853 and reported in the VCH to occur “in some numbers locally” within this area. This ancient introduction has a patchy distribution on lime-rich soils in southern England, but is becoming increasingly rare across Europe and is legally protected.

occasional paper no. 20 an atlas of oxfordshire

Documents