Description: Usually found on the mid to low shore growing on the egg wrack (Ascophyllum nodosum) and other fucoid algae. The colony is made up of a cluster or salmon pink to orange coloured polyps, up to 3 cm high when fully extended.

Habitat: Usually found growing on fucoid algae, especially Ascophyllum nodosum, on sheltered shore that are exposed to tidal streams.

Ecology: Occurs on the mid to low shore in areas that are sheltered from wave action but exposed to tidal streams. It prefers to grow epiphytically on the egg wrack Ascophyllum nodosum and other fucoid species. It can tolerate low salinities and can also be found growing in estuarine conditions.

Distribution: A North Atlantic species occurring from the Arctic Ocean to as far south as Portugal. It is also found on the Atlantic coast of North America. It is common all around the coasts of Britain and Ireland.

Similar Species: The habit of growing on fucoid algae in the intertidal zone makes it unlikely that this species would be confused with any other.

Key Identification Features:

• Salmon pink or white coloured polyps
• Forms small clusters, mainly on fucoid algae
• Up to 3 cm tall but typically 1.5 to 2 cm

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

iNaturalist: Clava multicornis at iNaturalist World Species Observations database.

GBIF data for Clava multicornis

WoRMS: Clava multicornis at World Register of Marine Species. Accepted name: Clava multicornis (Forsskål, 1775). AphiaID: 117426.

Classification: Biota; Animalia; Cnidaria; Medusozoa; Hydrozoa; Hydroidolina; Anthoathecata; Filifera; Hydractiniidae; Clava