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.

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…

Look for the White water-lily in still and slow-moving water, such as ponds, ditches, lakes and canals. Its lily pads and massive, white flowers float at the water's surface.

Look for the Yellow water-lily in still and slow-moving water, such as ponds, ditches, lakes and canals. Its lily pads and cupped, yellow flowers float at the water's surface.

A recent colonist to south east England, the metallic-green willow emerald damselfly spends much of its time in the willow and alder trees that overhang ponds, lakes and canals.

Also known as the 'green drake mayfly', the common mayfly can be found around unpolluted wetlands, such as lakes and rivers. It has transparent, lacy wings and three long 'tails…

The emperor dragonfly is an impressively large and colourful dragonfly of ponds, lakes, canals and flooded gravel pits. It flies between June and August and even eats its prey on the wing.

As its name suggests, Himalayan balsam is from the Himalayas and was introduced here in 1839. It now an invasive weed of riverbanks and ditches, where it prevents native species from growing.