This volume of Bibliotheca Lichenologica presents a study of the diversity of lichens and lichenicolous fungi on leaves and conifer needles in Macaronesia and atlantic Europe. Additional information on foliicolous lichens and lichenicolous fungi for many more neighbouring countries [Norway, Denmark, the British Isles, the Netherlands, Belgium, France, Spain (mainland), Portugal (mainland), Canary Islands, Madeira, Azores] is included. A total of 150 taxa are treated, 109 are crustose lichens, 29 are macro lichens and 12 are lichenicolous fungi, 10 species are described as new (8 lichens and 2 lichenicolous fungi). Keys, descriptions, distribution and taxonomic discussions for all species and illustrations for 95 species are presented.

As result of this study, 10 lichen species are newly described: Arthonia portuensis van den Boom, Bacidina aeruginosa van den Boom, B. piceae van den Boom, Bryostigma lapalmae van den Boom & Ertz, Fellhanera azorica van den Boom, F. subnaevia van den Boom, F. subparvula van den Boom, Micarea epiphylla van den Boom and two lichenicolous fungi Nectriopsis bacidinae van den Boom, Opegrapha hyperphysciae van den Boom.

The book will be useful to anyone studying the lichens present in all neighbouring countries around the atlantic Europe.