BIOTIC Species Information for Alcyonidium diaphanum
Researched byOlwen Ager Data supplied byMarLIN
Refereed byThis information is not refereed.
Scientific nameAlcyonidium diaphanum Common nameSea chervil
MCS CodeY76 Recent SynonymsNone

PhylumBryozoa Subphylum
Superclass ClassGymnolaemata
Subclass OrderCtenostomatida
SuborderCarnosa FamilyAlcyonidiidae
GenusAlcyonidium Speciesdiaphanum

Additional InformationOther common names include "curly weed", "amber weed" and "ju-ju weed" (Pathmanaban et al., 2005).
Taxonomy References Hayward, 1985, Howson & Picton, 1997, Hayward & Ryland, 1995b, Hayward et al., 1996, Pathmanaban et al., 2005,
General Biology
Growth formCrustose soft
Feeding methodActive suspension feeder
Mobility/MovementPermanent attachment
Environmental positionEpifaunal
Typical food typesSuspended orgaic particulates and plankton HabitAttached
BioturbatorNot relevant FlexibilityHigh (>45 degrees)
FragilityIntermediate SizeMedium-large(21-50cm)
HeightUp to 50 cm. Growth RateInsufficient information
Adult dispersal potentialNone DependencyIndependent
General Biology Additional Information

Alcyonidium diaphanum is responsible for the allergic contact dermatitis termed 'Dogger Bank Itch', experienced mostly by fishermen and dock workers (Pathmanaban et al., 2005). Although previously not reported from any other fishing grounds around the British Isles (Hayward, 1985), and despite its name, Dogger Bank Itch has also been reported from trawler-men in le Havre, shell fishermen from Cornwall and fixed net fishermen in the eastern English Channel (Pathmanaban et al., 2005).

Biology References Hayward, 1985, Pathmanaban et al., 2005,
Distribution and Habitat
Distribution in Britain & IrelandFound around all British and Ireland coasts.
Global distributionCommon off all north European coasts.
Biogeographic rangeNot researched Depth rangeExtreme low water to 100m
MigratoryNon-migratory / Resident   
Distribution Additional InformationDense populations can be found in the Thames Estuary, along coasts of Netherlands and belgium, Bay of Seine and the northern Bristol Channel (Porter et al., 2001).

Substratum preferencesBedrock
Large to very large boulders
Small boulders
Physiographic preferences
Biological zone Wave exposure
Tidal stream strength/Water flow Salinity
Habitat Preferences Additional InformationNone entered
Distribution References NBN, 2002, Hayward, 1985, Hayward & Ryland, 1995b, Hayward et al., 1996, Picton & Costello, 1998, Porter et al., 2002, Pathmanaban et al., 2005, Porter et al., 2001,
Reproduction/Life History
Reproductive type Developmental mechanismLecithotrophic
Reproductive SeasonInsufficient information Reproductive LocationInsufficient information
Reproductive frequencyAnnual episodic Regeneration potential No
Life span6-10 years Age at reproductive maturity1 year
Generation timeInsufficient information FecundityInsufficient information
Egg/propagule sizeInsufficient information Fertilization typeInsufficient information
Larval/Juvenile dispersal potential<10m Larval settlement periodInsufficient information
Duration of larval stage<1 day   
Reproduction Preferences Additional InformationThe majority of bryozoans brood their embryos and release short lived lecithotrophic larvae (Reed, 1991). The larvae of Alcyonidium duplex hatch as fully developed larvae and settle soon after (Reed, 1991). Therefore, it is assumed that the larvae of Alcyonidium diaphanum are similar.
Reproduction References
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