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 in 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): any records outside these counties (southwest Ireland most likely) would be welcomed. Also from west coast of France.

Similar Species: Compare with Anthopleura ballii, Urticina felina, and Bunodactis verrucosa.

Key Identification Features:

• Warts usually with attached gravel.
• Irregular tentacle arrangement.

Distribution Map from NBN: Anthopleura thallia at National Biodiversity Network mapping facility, data for UK.

iNaturalist: Anthopleura thallia at iNaturalist World Species Observations database.

WoRMS: Anthopleura thallia at World Register of Marine Species. Accepted name: Anthopleura thallia (Gosse, 1854). AphiaID: 100812.

Classification: Biota; Animalia; Cnidaria; Anthozoa; Hexacorallia; Actiniaria; Enthemonae; Actinioidea; Actiniidae; Anthopleura