What many people don't realize is that lichens can be extremely rare and can suffer from habitat degradation and pollution, just like vascular plants and animals. While this threat has been recognized at a national level (many countries have red lists for lichen species), it has not been acknowledged at a global level. Until recently, the IUCN Red List included only four lichen taxa.
Anzia centrifuga (Parmeliaceae, included since 2014)
Cladonia perforata (Cladoniaceae, 2003)
Erioderma pedicellatum (Pannariaceae, 2003)
Gymnaderma insulare (Cladoniaceae, 2014),