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.

The smaller of our two UK seal species, common seals are also known as harbour seals. Despite being called "Common", they are actually less common than grey seals!

The tiny, grey-brown house mouse is one of our most successful mammals. It thrives around buildings but is less likely to be found in our houses these days due to better construction.

The hooded crow was thought to be the same species as the carrion crow, but they have now been separated. Less widespread than its cousin, look for it in North Scotland, Northern Ireland and the…