Cepaea nemoralis

This species is widespread in Europe, and is locally abundant (Kerney, Cameron and Jungbluth 1983).

The northern distribution boundary of Cepaea nemoralis is in Scotland and southern Scandinavia. The range extends south to the Iberian Peninsula and Croatia in the south. Capaea nemoralis is found in the western and eastern coasts of both Ireland and the UK, Belgium, and France. The eastward distribution extends to the northwestern areas of Poland. This species was introduced in southeastern Poland, where it currently thrives. Cepaea nemoralis was introduced into North America during the nineteenth century and is currently found in Virginia, New York, Ontario, and Massachusetts.

Biogeographic Regions: nearctic (Introduced ); palearctic (Native )

occurs (regularly, as a native taxon) in multiple nations

Canada

Origin: Exotic

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

United States

Origin: Exotic

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

Global Range: (>2,500,000 square km (greater than 1,000,000 square miles)) This species is native to western Europe but have been introduced widely including many places in the U.S. and Canada (Whitson, 2005; Burch, 1962).

Cepaea nemoralis has a yellow, pink, or brown shell. The shell contains as many as five dark bands (each 360 degree revolution constitutes one band). The shells are made up of different layers. The outer layer (periostracum) is made up of conchiolin and the layer directly layer is much thicker and is composed of calcium carbonate. Calcium is an important component of the shell and it is an important factor that determines the shell strength. Calcium concentrations vary from 319 to 359 mg/g. The shell strength, measured in Newtons required to break it, varies from 35 to 63 N. Cepaea nemoralis shell thickness varies from 0.17 to 0.21 mm. The dry weight of the shell varies from 0.43 to 0.72 g. The shell volume measures anywhere from 2230 to 3012 cubic mm.

Range mass: 0.72 (high) g.

Range basal metabolic rate: 0.014 to 0.251 cm^3 oxygen/hour.

Average basal metabolic rate: 0.134 cm^3 oxygen/hour.

Other Physical Features: ectothermic ; heterothermic ; polymorphic

Sexual Dimorphism: sexes alike

Habitat and Ecology

Systems

• Terrestrial

Cepaea nemoralis is found in habitats ranging from hedgerows to downland turf and from beech woods to sand dunes near the sea. This species is also found throughout grasses and herbs. A relatively small amount is found in Marram grass. Unbanded and yellow C. nemoralis are mostly found in open habitats. Colonies with a green background have a high proportion of yellow C. nemoralis. Yellow C. nemoralis can also be found in shaded areas and banded shells of this species are found in areas of hedgerows and mixed rough herbage. In areas where the type of land is discontinuous, branded C. nemoralis are found. In Southeastern Poland, where C. nemoralis has been introduced, the species is found in urban environments where it inhabits gardens, orchards, cemeteries, hedgerows and other vegetation made up of herbs. In the hot and dry months of the summer, C. nemoralis is also found in tall plants and plants with large leaves or stems. Two of these plants include goldenrod and Centaurea. During hibernation C. nemoralis are found underground on land and underwater where they can survive for 2-3 weeks.

Habitat Regions: temperate ; terrestrial

Terrestrial Biomes: savanna or grassland

Other Habitat Features: urban

Habitat Type: Terrestrial

Non-Migrant: No. All populations of this species make significant seasonal migrations.

Locally Migrant: No. No populations of this species make local extended movements (generally less than 200 km) at particular times of the year (e.g., to breeding or wintering grounds, to hibernation sites).

Locally Migrant: No. No populations of this species make annual migrations of over 200 km.

Cepaea nemoralis prefers to eat dead plant material rather than fresh. They also prefer to eat herbs rather than grasses. Adult C. nemoralis show greater selectivity in their eating habits than the juveniles, although they eat some grasses while juveniles do not. They eat Poterium sanguisorba and Leontodon hispidus. Lotus corniculatus and Urtica diocia are examples of rarely consumed greens. Cepaea nemoralis avoid vetch, shrub and grass in their diet. Remains of ants, beetles, spiders, mites, springtails and aphids are found in the diet of C. nemoralis, but these are probably the remains that were eaten along with greens and herbs.

In a colony that is as dense as 5 adults per square meter, the mean annual biomass consumed is 1.03 g per square meter. A large C. nemoralis can eat 125 mg of food per week, meaning a daily consumption rate of 59.5 mg of food per 1 g of dry tissue weight of the snail. Cepaea nemoralis relies on large lumps of food and its hydrolytic enzymes in its gut for nutrition. Vitamins A and B and some sterols are required components of C. nemoralis nutrition. Adults require sitosterol, a plant sterol.

Animal Foods: insects

Plant Foods: leaves; wood, bark, or stems; fruit; flowers

Primary Diet: herbivore (Folivore , Frugivore , Lignivore)

Phorid flies are parasitic on C. nemoralis.

Ecosystem Impact: biodegradation

Commensal/Parasitic Species:

• Phorid flies, Phoridae

Birds, mice, and rats are the most significant predators of Cepaea nemoralis. In Europe, the most common predator of C. nemoralis is song thrushes. Predators feed on snails by cracking the shells on nearby hard objects or with the use of their teeth.

Other predators of C. nemoralis include the rook, the brown rat, hedgehogs, moles, field mice, Sorex, rabbits, and maggots. Phorid flies are parasitic and consume C. nemoralis.

Anti-predator adaptations of C. nemoralis include the complexity of color and bands on shell varying with the complexity of the landscape, known as background matching. Brown shelled C. nemoralis are found in landward parts which are generally complex landscapes. Unbanded shells are found in the most pitted areas. The greatest complexity in the variation of shell colors and whether or not the shells are un/banded correlates with the amount of enclosed spaces such as pits that serve as amphitheaters for other organisms. Song Thrushes, a main predator of C. nemoralis, preys on shells that are distinguishable from the environment.

Another anti-predator adaptation of C. nemoralis is shell thickening. Thickening of the shell prevents the ability of a predator to crush the shell. It also increases the "handling time" of the snail. Increasing handling time makes C. nemoralis less energetically rewarding prey. Crushing resistance positively correlates with calcium concentration.

Known Predators:

• Song thrush, Turdus ericetorum
• Rook, Corvus frugilegus
• Brown rat, Rattus norvegicus
• Hedgehog, Erinaceus europaeus
• Moles, Talpidae
• Field mouse, Apodemus sylvaticus
• Rabbits, Leporidae
• Maggots
• Phorid flies, Phoridae

Anti-predator Adaptations: cryptic

Cepaea nemoralis (snail carrion (Cepaea nemoralis)) is prey of:
Psychoda humeralis
Spiniphora maculata
Megaselia brevicostalis
Megaselia tenebricola
Piophila vulgaris
Neoleria maritima
Leptocera luteilabris
Sphaerocera vaporariorum
Sarcophaga hirticrus
Sarcophaga nigriventris
Sarcophaga teretirostris
Muscina assimilis
Fannia canicularis
Hydrotaea occulta
Subhylemyia longula
Lasiomma octoguttatum
Craspedochoeta pullula

Based on studies in:
Wales (Forest, Plant substrate)

This list may not be complete but is based on published studies.

Note: For many non-migratory species, occurrences are roughly equivalent to populations.

Estimated Number of Occurrences: > 300

Comments: In New York, Hotopp and Pearce (2007) report it from four counties in the metro and Long Island area and on Lake Erie. It was introduced intentionally to Frederick Co., Maryland (Grimm, 1971) and is still present there today (Orstan and Pearce, 2010).

>1,000,000 individuals

Cepaea nemoralis is able to respond to painful and non-painful stimuli. During the night, C. nemoralis feels more pain. Calcium channels are involved in the regulation of neuronal functions in mollusks in a manner like vertebrates. Similar intermediary messenger systems also exist between Cepaea and rodents.

Cepaea nemoralis predominantly moves in an upwind direction. They first randomly move in any direction before following the upwind stream. The decision to move upwind is made when the odor of favored foods is detected.  Interactions between C. nemoralis exist. As the number of individuals within a colony increases, there is a decline in juvenile growth rates and birth rates. Limited resources is not the explanation because even in areas of normal competition, there is still growth rate and birth rate declines. This indicates that there is either a chemical or behavioral type of communication within the species that is responsible for the declination.

Communication Channels: visual ; tactile ; chemical

Perception Channels: visual ; infrared/heat ; tactile ; chemical ; magnetic

In Europe, from 30-80 eggs (2.3-3.0 mm in diameter) are laid and hatch in 15-20 days. High temperatures and low humidity reduce the snail's activity and therefore inhibits growth rate. Cepaea nemoralis can form the peristome lip, which indicates it is an adult, in one active season. Juveniles may take to three years to develop into adults.

The color variation in the shells of Cepaea nemoralis is determined genetically by allelic series. Yellow shell alleles are recessive to pink shell alleles, and both yellow and pink shell alleles are recessive to brown shell alleles. The unbanded shell allele is dominant to banded.

Cepaea nemoralis may live up to six years in the wild, but this is uncommon because of predation. In captivity, they may live up to 10 years. The average lifespan of C. nemoralis is 2.3 years. The survival rates of the young greatly differs and can range anywhere from 0.3 to 0.7. However, in most cases, the rate is closer to 0.3. It depends on the region and the temperature.

Range lifespan
Status: wild: 6 (high) years.

Average lifespan
Status: wild: 2.3 years.

Range lifespan
Status: captivity: 10 (high) years.

Average lifespan
Status: wild: 2.3 years.

Cepaea nemoralis is hermaphroditic and mates more than once. A mating partner for C. nemoralis is random, according to color, size and banding patterns. The snails can store sperm for long periods of time. Each individual C. nemoralis may produce offspring from several matings in each brood. The average number of mates per brood is two. Cross fertilization is obligatory.

The offspring of each C. nemoralis is divided into a number of broods that is produced over a period of months or even years. This makes it unlikely that the fates between different broods will mimic each other. Each brood consists of genetic contributions from one female parent and two male parents. This reduces the dependence of single parents for survival within a whole brood unit. This system of multiple mating and sperm storage protects organisms that are minimally mobile from complete fatality within a gene pool.

Courtship of C. nemoralis is elaborate. A calcareous dart is jabbed into a potential partner before mating begins. In order to prevent accidental mating between C. nemoralis and a closely related species, Cepaea hortensis, the two species have different darts.

Mating System: polygynandrous (promiscuous)

The breeding interval of Cepaea nemoralis runs from April through October. The relative seasons are spring, summer and the beginning of the fall. The number of offspring per brood is around 23. Eggs are laid simultaneously in a dug nest in soil. The snail's foot is used to create a cavity in soil for laying eggs. The laying of the eggs can take up to three days and when complete, its foot is used again to cover the nest.

The average number of hatched young per year is 33. The eggs of one brood may survive or die as a unit; however, once they hatch, the individual's survival is not correlated to the rest of the brood. High temperatures and low humidity reduce the snail's activity and therefore inhibits growth rate and egg production.

Breeding interval: This species breeds 1 to 2 times yearly.

Breeding season: Breeding season is from April to October.

Average number of offspring: 23.

Range age at sexual or reproductive maturity (female): 1 to 2 weeks.

Range age at sexual or reproductive maturity (male): 1 to 2 weeks.

Key Reproductive Features: seasonal breeding ; sequential hermaphrodite; sexual ; induced ovulation ; fertilization (Internal ); oviparous ; sperm-storing ; delayed fertilization

Cepaea nemoralis produces eggs at the same time and are laid in nest they dig and cover up with soil. Beyond hatching, there is no parental care.

Parental Investment: male parental care ; female parental care ; pre-fertilization

The following is a representative barcode sequence, the centroid of all available sequences for this species.

There are 2 barcode sequences available from BOLD and GenBank.  Below is a sequence of the barcode region Cytochrome oxidase subunit 1 (COI or COX1) from a member of the species.  See the BOLD taxonomy browser for more complete information about this specimen and other sequences.

Download FASTA File

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 3
Specimens with Barcodes: 15
Species With Barcodes: 1

Year Assessed

Assessor/s

Reviewer/s

Contributor/s

Justification

Cepaea nemoralis is listed as "least concern" in the Czech Republic. It is not specially listed by any other countries or organizations.

US Federal List: no special status

CITES: no special status

State of Michigan List: no special status

IUCN Red List of Threatened Species: no special status

Canada

Rounded National Status Rank: NNA - Not Applicable

United States

Rounded National Status Rank: NNA - Not Applicable

Rounded Global Status Rank: G5 - Secure

Reasons: This species is native to western Europe but have been introduced widely including many places in the U.S. and Canada (Whitson, 2005; Burch, 1962).

Population

Population Trend

Major Threats

Conservation Actions

Global Protection: Unknown whether any occurrences are appropriately protected and managed

There are no known adverse affects of Cepaea nemoralis on humans.

Cepaea nemoralis display a significant amount of polymorphism in their shells. This polymorphism has been the subject of many evolutionary studies in Europe.

Positive Impacts: research and education