Littorina littorea

Researched By	Angus Jackson	Data Supplied By	MarLIN
Refereed by	Dr David Reid
Taxonomy
Scientific name	Littorina littorea	Common name	Common periwinkle
MCS Code	W296	Recent Synonyms	None
Phylum	Mollusca	Subphylum
Superclass		Class	Gastropoda
Subclass	Prosobranchia	Order	Mesogastropoda
Suborder		Family	Littorinidae
Genus	Littorina	Species	littorea
Subspecies
Additional Information	Also commonly known as the 'edible periwinkle'. Young animals with spiral ridges may be confused with Littorina saxatilis. During the breeding season males are easily distinguished by the presence of a penis on the right hand side of the body. The taxonomy of the Gastropoda has been recently revised (see Ponder & Lindberg 1997, and Taylor 1996). Ponder & Lindberg (1997) suggest that Mesogastropoda should be included in a monophyletic clade, the Caenogastropoda. See Reid (1996) for a comprehensive review of the systematics and evolution of Littorina littorea.
Taxonomy References	Howson & Picton, 1997, Hayward et al., 1996, Campbell, 1994, Hayward & Ryland, 1995b, Graham, 1971, Fish & Fish, 1996, Rutherford, Web pages, Rosso, 1998, Fox, 1994(b), Hayes, 1926, Ponder & Lindberg, 1997, Taylor, 1996, Reid, 1996
General Biology
Growth form	Turbinate	Feeding method	Herbivore
Mobility/Movement	Crawler	Environmental position	Epifaunal
Typical food types	A range of fine green, brown and red algae, including Ulva lactuca, Ulva spp., Cladophora spp. and Ectocarpus spp.	Habit	Free living
Bioturbator	Not relevant	Flexibility	None (< 10 degrees)
Fragility	Robust	Size	Small-medium(3-10cm)
Height	Insufficient information	Growth Rate	0.065-0.097 mm/day
Adult dispersal potential	100-1000m	Dependency	Independent
Sociability	Gregarious
Toxic/Poisonous?	No
Additional Information	Size and growth rate measurements apply to shell height. Most work suggests that maturity is reached at between 10-12mm shell height. Littorina littorea has various biochemical adaptations that allow the stressful intertidal habitat to be exploited. The species tends to aggregate and form clusters in areas that are more favourable for them, such as rock pools, rather than drier areas. Males are believed to mature earlier than females but females mature at a smaller size. Animals are more active when submerged due to the lower cost of moving on mucus when under water.
Biology References	Hayward et al., 1996, Campbell, 1994, Hayward & Ryland, 1995b, Fish & Fish, 1996, Newell, 1958, Fish, 1972, Fretter & Graham, 1994, Erlandsson & Johannesson, 1992, Rutherford, Web pages, Fox, 1994(b), Davies & Beckwith, 1999, Yamada, 1987, Gardner & Thomas, 1987, Erlandsson & Kostylev, 1995
Distribution and Habitat
Distribution in Britain & Ireland	Found on all British coasts, though rare or absent in the Isles of Scilly and Channel Isles.
Global distribution	Distributed from northern Spain to the White Sea (northern Russia).
Biogeographic range	Not researched	Depth range	60 m
Migratory	Seasonal (environment)
Distribution Additional Information	The species is found most commonly on the lower shore and shallow subtidal but in ideal conditions may be found up to the high tide line. However, the lower limit is poorly defined and will depend on factors such as predation, latitude etc. Therefore, the species may be found in the infra- and circalittoral zones. However, in deeper water the species is only found as isolated individuals in very low densities. At least in northern Britain Littorina littorea migrates down shore as temperatures fall in autumn (to reduce exposure to sub-zero temperatures) and up shore as temperatures rise in spring; migration depends on local winter temperatures. When exposed to the air, the species usually remains inactive unless conditions are very moist.
Substratum preferences	Bedrock, Large to very large boulders, Small boulders, Cobbles, Pebbles, Gravel / shingle, Muddy gravel, Sandy mud, Muddy sand, Mud, Salt marsh	Physiographic preferences	Open coast, Estuary
Biological zone	Upper Eulittoral, Mid Eulittoral, Lower Eulittoral, Sublittoral Fringe	Wave exposure	Moderately Exposed, Sheltered, Very Sheltered, Extremely Sheltered, Ultra Sheltered
Tidal stream strength/Water flow	Strong (3-6 kn), Moderately Strong (1-3 kn), Weak (<1 kn), Very Weak (negligible)	Salinity	Variable (18-40 psu), Reduced (18-30 psu), Full (30-40 psu)
Habitat Additional Information
AMBI Group (Borja et al., 2000)	II
Distribution References	Hayward et al., 1996, Campbell, 1994, Hayward & Ryland, 1995b, Graham, 1971, Fish & Fish, 1996, Newell, 1958, Fish, 1972, Fretter & Graham, 1994, Rutherford, Web pages, Gendron, 1977, Gardner & Thomas, 1987
Reproduction/Life History
Reproductive type	Gonochoristic	Developmental mechanism	Planktotrophic, Oviparous
Reproductive Season	February to June	Reproductive Location	Water column
Reproductive frequency	Annual episodic	Regeneration potential	No
Life span	6-10 years	Age at reproductive maturity	<1 year
Generation time	3-5 years	Fecundity	Up to 100,000 for large females
Egg/propagule size	Egg capsules ca 1 mm across	Fertilization type	Internal
Larvae/Juveniles Larval/Juvenile dispersal potential >10km Larval settlement period Insufficient information Duration of larval stage 11-30 days
Additional Information	This species can breed throughout the year but the length and timing of the breeding period are extremely dependent on climatic conditions. Also, estuaries provide a more nutritious environment than the open coast (Fish, 1972). Sexes are separate, and fertilisation is internal. Littorina littorea sheds egg capsules directly into the sea. Egg capsules are about 1mm across and each biconvex capsule can contain up to nine eggs but normally there are only two or three eggs per capsule. Egg release is synchronized with spring tides. In estuaries the population matures earlier in the year and maximum spawning occurs in January. Fecundity value is up to 100,000 for a large female (27mm shell height) per year. Eggs are released on several separate occasions. Female fecundity increases with size. Larval settling time or pelagic phase can be up to six weeks. Males prefer to breed with larger, more fecund females. Parasitism by trematodes may cause sterility.
Reproduction References	Hayward et al., 1996, Fish & Fish, 1996, Fish, 1972, Fretter & Graham, 1994, Newell & Newell, 1977, Erlandsson & Johannesson, 1992, MBA, 1957, Rutherford, Web pages, Hughes & Roberts, 1980