Paludinella litorina

Researched By	Nicola White	Data Supplied By	MarLIN
Refereed by	Dennis R. Seaward
Taxonomy
Scientific name	Paludinella litorina	Common name	Lagoon snail
MCS Code	W405	Recent Synonyms	None
Phylum	Mollusca	Subphylum
Superclass		Class	Gastropoda
Subclass	Prosobranchia	Order	Mesogastropoda
Suborder		Family	Assimineidae
Genus	Paludinella	Species	litorina
Subspecies
Additional Information	The pulmonate Otina ovata is a frequent associate of Paludinella litorina, in caves etc. In shingle it often occurs with the pulmonates Ovatella myosotis and (slightly lower on the shore) Leucophytia bidentata, and the prosobranch Truncatella subcylindrica. 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.
Taxonomy References	Howson & Picton, 1997, Barnes, 1994, Light & Killeen, 1997, Fretter & Graham, 1978, Taylor, 1996, Ponder & Lindberg, 1997
General Biology
Growth form	Globose	Feeding method	Sub-surface deposit feeder, Surface deposit feeder
Mobility/Movement	Crawler	Environmental position	Epifaunal, Interstitial
Typical food types	No text entered	Habit	Free living
Bioturbator	Not relevant	Flexibility	None (< 10 degrees)
Fragility	Robust	Size	Very small(<1cm)
Height	Max. 2 mm	Growth Rate	Insufficient information
Adult dispersal potential	>10km	Dependency	Independent
Sociability	Gregarious
Toxic/Poisonous?	No
Additional Information	Very little data on biology found. The animal crawls by alternately extending the front and rear halves of the foot forward, producing a shuffling gait. The foot is short and rounded. It is found at low to moderate densities in narrow, linear habitats
Biology References	Light & Killeen, 1997, Fretter & Graham, 1978
Distribution and Habitat
Distribution in Britain & Ireland	Recorded from the Isle of Wight, the Fleet, North Devon, South Devon, Pembrokeshire, Cornwall and Isles of Scilly.
Global distribution	Primarily a Mediterranean species (absent from the Black Sea) which extends along Eastern Atlantic coasts from Madeira north to a limit on the south coast of England.
Biogeographic range	Not researched	Depth range	Not relevant
Migratory	Non-migratory / Resident
Distribution Additional Information	Paludinella litorina is probably under-recorded due to its small size, inaccessible habitat and the similarity of its shell to that of Littorina saxatilis. An update on the distribution of Paludinella litorina has been compiled by Light & Killeen (2001). Frequent molluscan associates are the pulmonate Otina ovata in the crevice or cave habitat, and the pulmonates Ovatella myosotis and Leucophytia bidentata and prosobranch Truncatella subcylindrica in shingle interstices. Other species particularly associated with Paludinella litorina are the Isopoda Ligia oceanica in cave habitats (unless Ligia oceanica is excessively dominant, then Paludinella litorina is excluded), and Bdella mites in the interstitial habitat of the upper shore shingle or boulders (Light & Killeen, 2001).
Substratum preferences	Bedrock, Caves, Under boulders, Crevices / fissures, Gravel / shingle	Physiographic preferences	Open coast, Isolated saline water (Lagoon)
Biological zone	Supralittoral, Upper Littoral Fringe, Lower Littoral Fringe	Wave exposure	Sheltered
Tidal stream strength/Water flow	Weak (<1 kn), Very Weak (negligible)	Salinity	Variable (18-40 psu)
Habitat Additional Information
Distribution References	Barnes, 1994, Light, 1998, Light & Killeen, 1997, Light & Killeen, 1998, Fretter & Graham, 1978, Seaward, 1991, Light & Killeen, 2001, Moore, 2002
Reproduction/Life History
Reproductive type	Insufficient information	Developmental mechanism	Insufficient information
Reproductive Season	Insufficient information	Reproductive Location	Insufficient information
Reproductive frequency	Insufficient information	Regeneration potential	No
Life span	Insufficient information	Age at reproductive maturity	Insufficient information
Generation time	Insufficient information	Fecundity	Insufficient information
Egg/propagule size	Insufficient information	Fertilization type	Insufficient information
Larvae/Juveniles Larval/Juvenile dispersal potential Insufficient information Larval settlement period Insufficient information Duration of larval stage Insufficient information
Additional Information	Graham (1988) suggests that a free larval stage is unlikely to occur.
Reproduction References	Graham, 1988