Spirorbis Worms in the Crevice of an Oarweed Frond

Spirorbis worms in a crevice of an oarweed frond

These crescent-shaped or helical creatures are a species of Spirorbis, a genus of polychaete worms. Polychaete worms have many segments with legs and hair, as well as a head and a tail. So, they aren't much like terrestrial worms. Spirorbis make their tiny shells: the larger shells in the image are about the size of a peppercorn. The fine nets protrucing from the mouths of the shells are feeding tentacles. Spirorbis are common in the north Atlantic and north Pacific.

In this case, Spirorbis have settled on an oarweed, Laminaria farlowii. This species of kelp is common in the Channel Islands. It's edible, and said to be similar to Japanese kombu, a type of edible kelp harvested in Hokkaido. Confusingly, Japanese kombucha is made of fermented kombu, but American and European kombucha is made of fermented green tea.

The base of an oarweed frond. Each white dot is the shell of a Spirorbis worm.

A close view of Spirorbis worms on Laminaria kelp. On the green, worm-free regions, you can see the worms on the other side of the kelp, where the hills on this side are valleys on the other.