Sinistral Spiral Tubeworm

Spirorbis borealis

SIZE AND DESCRIPTION

Diameter 3–5mm. Tiny coiled calcareous shells on seaweeds that look more like molluscs than worms. When underwater, the green tentacles of the worms can be seen. The rest of the time they appear as immobile clockwise-coiled white tubes. There are several similar species.

HABITAT AND ECOLOGY

Very common and often extremely abundant on the middle and lower shores, on brown seaweeds such as kelps and wracks, as well as on rocks and stones.

DISTRIBUTION

Occurs across the Atlantic, English Channel, North Sea and Mediterranean.

Greenleaf Worm

Eulalia viridis

SIZE AND DESCRIPTION

Length to 15cm. Attractive and conspicuous long, thin and slow-moving green worm with paddle-like legs. Body may be made up of 50–200 segments, and is bright grass-green. King Rag Worm (Nereis virens) has a similar colour and leg shape, but is usually much larger.

HABITAT AND ECOLOGY

Commonly seen creeping around on rocks at low tide, especially in dull weather, stretching and contracting slowly. Also lives, often unseen, in rock crevices.

DISTRIBUTION

Common in the Atlantic, English Channel, North Sea, western Baltic and Mediterranean.