Phylum: Rhodophyta   Family: Rhodomelaceae

Melanothamnus harveyi  (Bailey) Díaz-Tapia & Maggs, 2017

Harvey's Siphon Weed

A short epiphyte with a dense cluster of rhizoids when growing on Codium (a preferred host), but other seaweeds also used. Found intertidally and off-shore, but infrequently recorded

References: 
Maggs & Hommersand (1993) - Seaweeds of the British Isles, Volume 1 Rhodophyta, Part 3A Ceramiales