BIOTIC Species Information for Mediomastus fragilis
Researched byCharlotte Marshall Data supplied byMarLIN
Refereed byThis information is not refereed.
Scientific nameMediomastus fragilis Common nameA bristleworm
MCS CodeP919 Recent Synonyms

PhylumAnnelida Subphylum
Superclass ClassPolychaeta
Subclass OrderCapitellida
Suborder FamilyCapitellidae
GenusMediomastus Speciesfragilis

Additional InformationNone entered
Taxonomy References
General Biology
Growth formVermiform segmented
Feeding methodSub-surface deposit feeder
Environmental positionEpibenthic
Typical food typesInsufficient information HabitTubiculous
BioturbatorNot researched FlexibilityHigh (>45 degrees)
FragilityFragile SizeSmall-medium(3-10cm)
HeightInsufficient information Growth RateInsufficient information
Adult dispersal potential100-1000m DependencyIndependent
General Biology Additional InformationLives in permanent vertical sandy tubes (Rasmussen, 1973). Up to 10 cm long (Hayward & Ryland, 1995b). Rasmussen (1973) noted that the species has little ability to migrate.
Biology References
Distribution and Habitat
Distribution in Britain & IrelandNorth Sea & English Channel (Hayward & Ryland, 1995b).
Global distributionNE Atlantic & Med (Hayward & Ryland, 1995b).
Biogeographic rangeNot researched Depth rangeLower shore to shallow sublittoral.
Distribution Additional Information

Substratum preferencesMuddy gravel
Sandy mud
Muddy sand
Physiographic preferences
Biological zone Wave exposure
Tidal stream strength/Water flow Salinity
Habitat Preferences Additional Information
Distribution References Hansen, 1993, Rasmussen, 1973, Hayward & Ryland, 1995b,
Reproduction/Life History
Reproductive type Developmental mechanismPlanktotrophic
Reproductive Season Reproductive Location
Reproductive frequencyAnnual episodic Regeneration potential No
Life spanInsufficient information Age at reproductive maturityInsufficient information
Generation timeInsufficient information Fecundity
Egg/propagule size Fertilization type
Larval/Juvenile dispersal potentialVery limited (<1m) Larval settlement period
Duration of larval stageInsufficient information   
Reproduction Preferences Additional InformationEgg masses attached to sediment with mucous threads in lab (Hansen, 1993). Restricted spawning period at start of April (Rasmussen, 1973).
Reproduction References Hansen, 1993, Rasmussen, 1973, Warren, 1979,
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