The seas around the UK are home to creatures as wondrous as any found in more exotic waters

Long-snouted seahorse (Hippocampus guttulatus)

With its protruding spines, downward gaze and prehensile tail, this most beguiling fish looks like a shy, prehistoric ghost. Floating upright, it hangs motionless waiting for its prey to pass, which it then sucks up through its long snout. Found in seagrass habitats from Scotland to Dorset.

Moon jellyfish (Aurelia aurita)

Most often seen when masses, known as a ‘bloom’, are washed up on the beach. Which is a shame, as they look most beautiful floating in transparent clusters. Moon jellyfish can grow up to 40cm in diameter and have short hairy tentacles that hang from their dome like a fringe. They are mostly harmless, though may sting sensitive skin.

Brittle star (Ophiothrix fragilis)

This elegant starfish has long slender arms which they can cleverly self-amputate if being attacked; the arms regrow. Brittle stars prefer to live in great gangs (called ‘aggregations’) on the sea bed, their arms raised to catch plankton; can number up to 1,500 per square metre. Usually in deep water but sometimes under boulders and in rockpools.

Snakelocks anemone (Anemonia viridis)

Unlike other anemones, Snakelocks anemone’s bright-green tentacles remain out all the time: all the better to sting and capture small fish. They can be found on the seabed, attached to large seaweeds, and in sunny rockpools, where their flowing tentacles with their purple tips sift through the passing currents.

Goose barnacle (Lepas anatifera)

Attached to rocks and other objects by a long black penduncle and with a chalky white shell which opens to reveal spiky fronds, this unusual creature has an alien-like quality.

Spiny spider crab (Maja squinado)

Often disguised by seaweed and sponges that grow all over it, this large knobbly crustacean has long-jointed legs, small claws and spiky shell. It can be found in South and West England and its sustainable numbers mean it’s increasingly eaten in the UK, although most are exported to France and Spain.