Look for the wood warbler singing from the canopy of oak woodlands in the north and west of the UK. Green above, it has a distinctive, bright yellow throat and eyestripe.

Considered Britain's most threatened butterfly, the high brown fritillary can be only be found in a few areas of England and Wales.

At nearly 7 cm long (including the female's long ovipositor), the great green bush-cricket certainly lives up to its name! It can be found in grassland, scrub and woodland rides in Southern…

Parsley fern lives up to its name - the pale green fronds form in clusters among rocks and look just like parsley. Look out for it in upland areas, particularly in Wales and Cumbria.

The raven is famous for being the imposing, all-black bird that guards the Tower of London. Wild birds live in forests, and upland and coastal areas in the north and west of the UK.

Mae’r dyfrgi hyblyg yn nofiwr ardderchog a gellir ei weld yn hela mewn gwlybdiroedd ac afonydd ac ar hyd yr arfordir – rhowch gynnig ar arfordir gorllewinol yr Alban, Gorllewin Cymru, y West…

Despite its name, the marsh tit actually lives in woodland and parks in England and Wales. It is very similar to the willow tit, but has a glossier black cap and a 'pitchoo' call that…

A scarce but distinctive brown seaweed with curved, funnel-shaped fronds. It is a warmer water species at the northern edge of its range on the south coast of England.

The sessile oak is so-called because its acorns are not held on stalks like those of the familiar English oak. It can be found in woodlands mainly in the north and west of the UK.