[1][2] The gnome's hat hydroid grows to about 3 cm tall.

It is a small conical hydroid with 30-40 adhesive knobs at its base.

The cone is made up of 400-600 densely packed warty tentacles which contain the stinging cells.

[1] This species is found around the southern African coast from Luderitz in Namibia to East London from the subtidal to at least 27m underwater.

[1] These animals are usually found among red seaweed and brown seagrass, singly or in small groups.