Often confused with the larger but similarly shaped lion’s mane jellyfish, the blue jellyfish can be colourless when young and develop a striking blue-purple bell as it matures.

Look for the small, pink, pea-shaped flowers of Common restharrow on chalk and limestone grasslands, and in coastal areas, during summer.

Enchanter's nightshade is a hairy plant, with rounded leaves that taper to a fine tip, and clusters of small, pinky-white flowers in summer.

As its name suggests, the scarlet elfcup is a bright red, cup-shaped fungus. It is widespread, but scarce, and can be found on fallen twigs and branches, in shady, damp places.

A handsome fish, the tench has olive-green flanks, powerful fins and distinctive red eyes. It can be found in lowland lakes and slow-flowing rivers around the UK.

A small colourful sea slug that can be found grazing on sea mats on the rocky shore and beyond the low water mark.