An easily overlooked orchid, the Common twayblade is yellow-green and less showy than other UK orchids. Look for it in woodlands and grasslands on chalky soils, in particular.

As its name suggests, Sea spurge is found at the coast. It is an attractive plant that displays cup-shaped, greeny-yellow flowers and fleshy, grey-green leaves.

Native oysters are a staple of our seas and our plates - but our love of their taste has lead to a sharp decline all around the UK.

The variable damselfly looks a lot like the azure damselfly, but is much less common throughout most of the UK.

Our largest shieldbug, the red-and-green hawthorn shieldbug can be seen in gardens, parks and woodlands, feeding on hawthorn, rowan and whitebeam. The adults hibernate over winter.

An attractive, green-and-yellow bird, the siskin regularly visits birdtables and feeders in gardens. Look for the bright yellow barring on its black wings, and the black crown of the males.