When we hear the terms “biodiversity crisis” and “mass extinction”, charismatic animals such as tigers, rhinos and sea turtles often spring to mind. But what about the small, inconspicuous species that play an important role in our ecosystems despite their size? Do they receive the attention and protection they need? Mosses may seem insignificant, but they form a rich and widespread group with around 20,000 species worldwide. Despite their small size, they play an important role in many ecosystems, for example by retaining moisture, serving as carbon sinks and contributing to nitrogen fixation in forests. Yet over 30 per cent of European species are endangered or potentially endangered. Many are poorly researched and often inadequately protected.