One of the most colourful fish in UK seas, the cuckoo wrasse looks like it belongs in the tropics. Don't be fooled though, it's very much a native species.

A scarce tree of England and Wales, the Large-leaved lime is the rarest of our native limes. It is tall and broad, and can be found in forests and parks, where it is frequently planted.

Sand sedge is an important feature of our coastal sand dunes, helping to stabilise the dunes, which allows them to grow up and become colonised by other species.

The song of the skylark has been the subject of many great musical and literary works. A quintessential feature of our farmland and grasslands habitats, it is declining rapidly with habitat loss…

Bittersweet is a nightshade, so is toxic; its bright red berries may be tempting, but can cause serious illness. Found in hedgerows and gardens, it has purple flowers with yellow stamens.

The muntjac deer was introduced into the UK from China in the 20th century. It has gained a stronghold in southeast England, where it can cause damage to our woods through browsing.

The oak marble gall wasp produces brown, marble-shaped growths, or 'galls', on oak twigs. Inside the gall, the larvae of the wasp feed on the host tissues, but cause little damage.

A scarce and declining bird, the tree sparrow can be spotted on farmland and in woodlands; it is not an urban bird in the UK. It has a brown cap and black cheek-spots, unlike the similar house…

The sanderling scampers about the waves looking for marine crustaceans, fish and even jellyfish to eat. It visits the UK in winter from its Arctic breeding grounds, but can also be seen as it…