Description: Growing from a small basal disc to a length of 10 to 20 cms generally branching only a few times. Reddish brown in colour and very mucilaginous in texture.

Habitat: Common. Epilithic in rock pools.

Distribution: Widespread around the British Isles except in south-eastern England. Europe: Medirerranean, Azores, Portugal, Spain, Netherlands and Norway. Atlantic coast of North America: Canada to Connecticut and Long Island. Further afield: the Canary Islands.

Similar Species: Helminthocladia calvadosa and Helminthora divaricata from which it is distinguished by having few side branches which are not markedly narrower than the main axis.

Key Identification Features:

• Worm-like, gelatinous.

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

iNaturalist: Nemalion helminthoides at iNaturalist World Species Observations database.

WoRMS: Nemalion helminthoides at World Register of Marine Species.