Unsung wildlife heroes of England's national parks - in pictures

Many people are aware of the endangered hedgehog, red squirrel or tortoiseshell butterfly, but little attention is given to the less photogenic species that are just as important to the British ecosystem. 'Unsung heroes' such as the bog hoverfly and tadpole shrimp also reflect the diversity and quality of habitats found in England's national parks and the ongoing conservation work to protect them