On oceanic islands, the evolution of plants and animals with particular characteristics is favoured due to their isolation, populations normally comprising a large number of unique, endemic species. The Madeira and Selvagens archipelagos are considered biodiversity hotspots, containing an especially rich bryoflora. Due to its characteristically small size, this taxonomic group does not get much attention in conservation programmes. However, these plants are an important component of terrestrial ecosystems, representing a major part of biodiversity and playing a vital role in the ecosystem's functioning. As such, the development of the first Red List for Madeira and Selvagens Archipelagos has the potential to guide conservation efforts focused on taxa and habitats where threatened species and endemics are better represented. By applying the International Union for Conservation of Nature and Natural Resources (IUCN) criteria, recently revised to apply to small islands, it was possible to obtain the percentage of threatened taxa present in the archipelagos (23.6%), and for each habitat type. It was verified that high mountain habitats and the Laurel forest represent areas that host higher percentages of threatened taxa (29.5% and 22.2%). An important result of the present Red List is the identification of hotspots for bryophyte diversity, supporting the definition of reserves/microreserves. The information obtained can also be linked up with the Red Lists of other taxonomic groups to work towards the definition of a more holistic conservation strategy.

Systematic and biogeographic relationships of mainly European and North American taxa of the moss genus Leucodon subg. Leucodon are inferred by phylogenetic reconstructions and haplotype analyses, based on sequence data from three plastid regions and nrITS. The two Macaronesian endemic species L. canariensis and L. treleasei are clearly separated from each other and from L. sciuroides, which is widespread in Eurasia including Macaronesia. A well‐supported sister‐group relationship with the American species L. curvirostris and L. julaceus indicates a New World ancestor of L. treleasei, which is probably a neoendemic species that colonized the Macaronesian islands after (recent) dispersal. The position of L. canariensis sister to the clade of L. treleasei and the American species is less well‐supported, leaving its evolutionary history ambiguous. The Eastern North American L. andrewsianus is neither molecularly nor morphologically unambiguously distinguishable from L. sciuroides. Synonymisation of L. andrewsianus with L. sciuroides solves the long‐debated question whether the latter species occurs in North America, and results in a Holarctic instead of Palaearctic distribution pattern of L. sciuroides. The Afromontane L. dracaenae cannot be clearly separated from L. sciuroides as well, whereas the Eastern Mediterranean to Central Asian L. immersus differs from L. sciuroides by few substitutions and indels as well as morphologically by the short seta and immersed capsule. Further analyses are necessary before taxonomic conclusions should be inferred for L. dracaenae and L. immersus. Intraspecific diversity in L. sciuroides does not support recognition of the mainly Mediterranean var. morensis. Instead, a basic separation of Mediterranean (plus Macaronesian) versus non‐Mediterranean haplotypes is indicated. The higher haplotype diversity in the Mediterranean (and Macaronesia) in contrast to the other parts of Europe is in accordance with genetic depletion in formerly glaciated areas.

The volatiles isolated by distillation-extraction from 48 samples of seven liverwort Radula species collected on Azores and Madeira archipelagos and mainland Portugal, as well as one from Switzerland, were analysed by GC and GC-MS. Cluster analysis of the volatiles composition resulted in two major clusters. The chemically very diverse cluster I included the oil samples of Radula aquilegia from Madeira, R. jonesii, R. holtii, R. nudicaulis, R. lindenbergiana as well as R. complanata from Switzerland. Cluster II was characterized by high relative amounts of several sesquiterpenes and included the oil samples of R. aquilegia from the Azores as well as R. carringtonii and R. wichurae. 3-Methoxy bibenzyl was the major oil component from R. complanata and R. lindenbergiana. Except for R. aquilegia and the closely related species R. complanata and R. lindenbergiana, the cluster analysis allows distinction of all studied species, indicating the chemotaxonomical value of the volatile oil characters.

The essential oils isolated from twigs of Juniperus cedrus Webb & Berth. grown on Madeira were analysed by GC, GC-MS and 13 C-NMR. The oils consisted mainly of monoterpene hydrocarbons (53.1-87.8%), the main ones being˛-pinene (19.6-55.3%), limonene (17.3-32.7%) and -3-carene (5.5-15.7%). The sesquiterpenoid fraction (4.1-22.3%) was dominated by E-caryophyllene (1.6-7.4%), while sandaracopimaradiene (0.1-6.1%), isoabienol (0.5-1.3%) and trans-totarol (0.4-2.2%) were the main diterpenoids (2.2-11.9%). Oct-1-en-3-ol (1.0-2.2%) was the major constituent of the non-terpenic fraction (1.3-2.7%). The composition of our oil samples differed to some extent from that reported for J. cedrus oil grown on the Canary Islands.

Essential oils isolated by distillation-extraction from P. bifaria, P. maderensis, P. retrorsa and P. stricta, collected on Madeira, were analysed by GC and GC-MS. Methyl everninate (1-35%), peculiaroxide (13-16%) and enteudesm-4(15)-ene-6-one (9-19%) were the main components in all P. bifaria specimens analysed. Terpinolene (34-60%) dominated the oils isolated from P. maderensis specimens. β β β β β-Phellandrene (16-46%) was the main component of two of the three specimens of P. retrorsa, allo-ocimene (15%), terpinolene (13%), peculiaroxide (12%) and neo-allo-ocimene (10%) being the main components of the third specimen. P. stricta oils were dominated by peculiaroxide (11-21%), allo-ocimene (7-19%), bicyclogermacrene (4-17%), neo-allo-ocimene (4-11%) and spathulenol (2-14%). Essential oil cluster analysis showed a high degree of similarity between three of the four species studied, the least correlated being P. maderensis oils.