Astropecten irregularis

Researched By	Morvan Barnes & Sean Lindsley-Leake	Data Supplied By	MarLIN
Refereed by	This information is not refereed
Taxonomy
Scientific name	Astropecten irregularis	Common name	A starfish
MCS Code	ZB25	Recent Synonyms	Crenaster d'Orbigny, 1850
Phylum	Echinodermata	Subphylum	Asterozoa
Superclass		Class	Asteroidea
Subclass		Order	Paxillosida
Suborder		Family	Astropectinidae
Genus	Astropecten	Species	irregularis
Subspecies
Additional Information
Taxonomy References	Hayward et al., 1996, Hayward & Ryland, 1995b, Picton, 1993, Fish & Fish, 1996, Mortensen, 1927, Howson & Picton, 1997
General Biology
Growth form	Stellate, Radial	Feeding method	Predator, Scavenger
Mobility/Movement	Crawler, Crawler	Environmental position	Epibenthic
Typical food types	Large benthic invertebrates including molluscs, particularly the clam Spisula subtruncata, polychaetes, crustaceans, and other echinoderms and carrion.	Habit	Free living
Bioturbator		Flexibility	High (>45 degrees)
Fragility	Intermediate	Size	Small-medium(3-10cm)
Height	not relevant	Growth Rate	17 cm/year at most
Adult dispersal potential	1km-10km	Dependency	Independent
Sociability	Gregarious
Toxic/Poisonous?	No
Additional Information	Growth rate There is considerable irregularity in the growth rate of starfish, especially during their first year. Growth rates of Astropecten irregularis are also highly seasonal and dependent on food availability, reaching 17 cm/year. Maximum growth occurs between March and April and between August and November.
Biology References	Hayward et al., 1996, Hayward & Ryland, 1995b, Picton, 1993, Fish & Fish, 1996, Mortensen, 1927, Freeman et al, 2001
Distribution and Habitat
Distribution in Britain & Ireland	Found throughout British and Irish coastal waters.
Global distribution	Found in north-west European waters, predominantly in the British Isles and Ireland but also north-east France, Belgium, Holland, Germany, Denmark and Norway.
Biogeographic range	Temperate.	Depth range	10 to 1000 m.
Migratory	Seasonal (feeding)
Distribution Additional Information
Substratum preferences	Gravelley sand, Muddy sand, Fine clean sand, Coarse clean sand	Physiographic preferences	Strait / sound, Offshore seabed, Open coast
Biological zone	Bathybenthic (Bathyal), Circalittoral Offshore, Lower Circalittoral, Upper Circalittoral, Lower Infralittoral, Upper Infralittoral	Wave exposure	Field unresearched
Tidal stream strength/Water flow	Field unresearched	Salinity	Full (30-40 psu)
Habitat Additional Information
AMBI Group (Borja et al., 2000)	I
Distribution References	Hayward et al., 1996, Hayward & Ryland, 1995b, Picton, 1993, Fish & Fish, 1996, Mortensen, 1927, NBN, 2002, Picton & Costello, 1998, JNCC, 1999
Reproduction/Life History
Reproductive type	Gonochoristic	Developmental mechanism	Lecithotrophic, Planktotrophic
Reproductive Season	May to June	Reproductive Location	Water column
Reproductive frequency	Annual episodic	Regeneration potential	Yes
Life span	3-5 years	Age at reproductive maturity	2-3 years
Generation time	Insufficient information	Fecundity	Insufficient information
Egg/propagule size	100-200 µm	Fertilization type	External
Larvae/Juveniles Larval/Juvenile dispersal potential >10km Larval settlement period Insufficient information Duration of larval stage 11-30 days
Additional Information	There is a great deal of variation within the genus for larval duration and egg size. Larger egg size corresponds with shorter larval period. There is also variation in the developmental mechanism with Grant & Tyler (1986) describing planktotrophic binnaria larvae for Astropecten irregularis and McEdward & Janies (1993) describing lecithotrophic larvae.
Reproduction References	McEdward & Janies, 1993, Freeman et al, 2001, McEdward & Morgan, 2001, Newth, 1925, Henry et al, 1991, Obrebski, 1979, Grant & Tyler, 1986, Tillin et al., 2006