Snakelocks anemones have a squat greyish-brown body and up to 200 long, wavy, snake-like tentacles that give them their name. They live attached to rocks or blades of eel-grass in sunny spots in inter–tidal pools and in shallow seas down to about 20m. The tentacles are normally bright green with purple tips and rarely retracted.  

Behaviour

Tends to be sessile and is normally the only sea anemone species in a pool, fighting off other species. They are frequently found living in colonies. 

A major characteristic of snakelocks anenome is that it interacts in many symbiotic relationships. The anemone contains symbiotic algae called zooxanthellae, found in the anemone’s tissues. The zooxanthellae provide food while the anemone provides nitrogen, so the former is thought to improve the long term survival of the anemone. The spider crab and snakelocks anenome often enjoy a commensal relationship; the anemone providing protection for the spider crab, which is immune to a possibly dangerous sting. 

Stinging cells known as cnidocysts, which line the anemone’s tentacles, are used to capture prey, such as prawns, small fish and sea snails.  

Snakelocks anemone can live for up to 60 years!

Size

• Width: up to 20cm
• Tentacle length: up to 18cm
• Weight: 10-18g

Status

Common; no specific conservation measures are in place. 

Distribution

Found on the southern and western shores of Britain, extending all around the west coast of Scotland as far north as Orkney.

When to see

All year round.

Facts

• Snakelocks anemone cells contain a special protein that makes them glow fluorescent green under ultraviolet light. 

• When poked with fingers, the tentacles feel incredibly sticky. However, they can produce a powerful sting and cause a rash on areas of thin human skin. 

• As with all cnidarians (sea anemones, corals and jellyfish), there is no anus; undigested waste is regurgitated back out through the mouth which lies embedded between the tentacles. 

• The snakelocks anemone is oviparous, meaning the eggs are laid outside the mother’s body. However, this sexual process for reproduction is less common than an asexual longitudinal fission process. Longitudinal fission is a literal splitting of the sea anemone, resulting in groups of individuals with identical colouring and markings.