Scytosiphon lomentaria is a littoral brown seaweed with an irregularly lobed many filamentous form. It is a member of the Phaeophyta in the order Dictyosiphonales and grows attached to shells and stones in rock-pools and in near-shore waters. The attachment to the substrate is by a small disc shaped holdfast.
Clade: Chromista (Algae)
Species: Scytosiphon lomentaria