CNIDARIA : ACTINIARIA : Actiniidae | SEA ANEMONES AND HYDROIDS |
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Anthopleura thallia |
Description: The column of this sea anemone is divided into a tall scapus and capitulum, with a parapet and fosse. The scapus has irregular vertical rows of warts which are largest and often confluent on the parapet. These warts may have gravel stuck to them. The tentacles are rather stiffly held and irregularly arranged. The column is green, grey, brown, or reddish. The tentacles are usually spotted with white but may be plain. Disc with a pattern which is variably coloured - yellow, pink, grey, red, orange, green, etc. Size up to 30mm across base, 50mm across tentacles. Reproduces by longitudinal fission.
Habitat: Found on exposed rocky shores in pools, gullies and clefts; often buried in gravel and amongst mussels in small pools; rarely in sheltered localities. On shore from mid-tide level to low-water mark; any records from sublittoral habitats would be welcomed.
Distribution: Only found in the extreme southwest of England and Wales - Devon, Cornwall, Dyfed (Pembrokshire). Recently found in Donegal, NW Ireland. Also from west coast of France. A record from Loch Maddy, outer Hebrides, Scotland is now considered to be Sagartia ornata.
Similar Species: Compare with Anthopleura ballii, Urticina felina, and Aulactinia verrucosa.
Key Identification Features:
Distribution Map: NBN map : National Biodiversity Network mapping facility, data for UK.
WoRMS: Species record : World Register of Marine Species.
iNaturalist: Species account : iNaturalist World Species Observations database
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Picton, B.E. & Morrow, C.C. (2016). Anthopleura thallia (Gosse, 1854). [In] Encyclopedia of Marine Life of Britain and Ireland. https://www.habitas.org.uk/marinelife/species.asp?item=D11800 Accessed on 2025-02-08 |
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