Hidden lichens of the Italian Alps and Northern Apennines reveal hundreds of new records

Deep in the high valleys of the Italian Alps and along the windswept ridges of the Northern Apennines, an intensive search for lichens has turned up hundreds of records that were previously unknown to science’s maps of Italy. A newly published synthesis in MycoKeys reports 518 occurrences corresponding to 288 lichen taxa, of which 33 are new to Italy and 255 are newly recorded for at least one Italian administrative region. The work, based on years of intensified field sampling combined with critical re-examination of herbarium specimens, offers one of the most substantial updates to Italian lichenology in decades and carries a pointed warning about the fate of cold-adapted species on a warming planet.

The motivation behind the study is urgency. Rapid climate change is progressing in mountain regions at rates approximately twice those observed in adjacent lowlands, and scientists fear that range-restricted, cold-adapted lichens may lose their suitable habitat before their distributions are even documented. Lichens, the symbiotic partnerships between fungi and photosynthetic partners, are among the most informative indicators of past and present environmental conditions in alpine ecosystems. Many are extremely substrate-specific and microclimate-sensitive, which makes them both vulnerable to environmental shifts and exceptionally valuable as biogeographical signals. Yet knowledge of where they occur, particularly in the less-studied Northern Apennines, has long been incomplete.

The Italian Alps are among the best-explored lichen landscapes on Earth, with more than 3,000 taxa recorded to date, a legacy rooted in a lichenological tradition stretching back to the nineteenth century. Italy contains a substantial portion of the Alpine system, from the Maritime Alps in Liguria to the Julian Alps in Friuli Venezia Giulia, spanning a remarkable diversity of rock types, from carbonate and clastic sedimentary rocks to metamorphic continental margin rocks and ophiolitic oceanic rocks shaped by Alpine orogenesis. Climatic diversity is equally striking: alpine climate zones above the tree line associated with glaciers and tundra, moist boreal belts with cool to cold winters, cool temperate montane belts, and scattered inner Alpine valleys with continental, semi-arid conditions.

The Northern Apennines, by contrast, have historically been undersampled, especially at high elevations. Although their peaks rarely exceed 2,000 meters, these mountains retain a pronounced arctic-boreal character, with many cold-adapted species reaching their southernmost distribution limits there. The chain lies at the biogeographical interface between the Boreal and Mediterranean regions, producing a distinctive assemblage in which boreal relicts and Mediterranean elements coexist across short spatial scales. During the Local Last Glacial Maximum in the Pleistocene, the Northern Apennines hosted more than 100 valley and mountain glaciers covering more than 260 square kilometers, leaving relict glacial landforms and deposits that still shape today’s microhabitats.

The new study draws on both fresh collections and museum treasures. Approximately 53 percent of the reported occurrences derive from specimens newly collected during the last seven years, while about 57 percent come from data-mining and taxonomic revision of already available herbarium material, including specimens stored in Graz and Trieste. Identification combined dissecting and compound microscopy with routine chemical spot tests, standardized thin-layer chromatography or HPTLC where necessary, and, for cryptic or poorly known taxa, molecular sequencing of the internal transcribed spacer region of fungal DNA. Nine newly generated ITS sequences were evaluated through BLASTn searches and submitted to GenBank, providing genetic evidence to complement morphological and chemical data.

The regional breakdown of new records is impressive across the board: 91 taxa added to Piemonte, 63 to Veneto, 51 to Trentino-Alto Adige, 40 to Liguria, 34 to Emilia-Romagna, 25 to Friuli Venezia Giulia, 21 to Lombardia, 18 to Valle d’Aosta, and 4 to Toscana. Thirty-eight taxa were new to the Italian Alps and 18 to the Northern Apennines, while 15 were new to the entire Apennine chain. The apparent sampling imbalance, biased toward the Alps, partly reflects the legacy of nineteenth-century lichenological studies in that system, whereas systematic exploration of the Northern Apennines has only recently resumed, yet the findings demonstrate considerable potential for further discoveries in that chain as well.

From a biogeographical perspective, the data considerably enlarge the known distributional ranges of many species along the Alpine chain, with several so-called eastern or western Alpine species actually present throughout the range. More strikingly, the high incidence of species with boreal-montane to arctic-alpine distributions in the Northern Apennines supports the hypothesis that these mountains act as southern outposts for elements of the arctic-boreal biota, mirroring patterns previously documented for vascular plants. Cold-adapted taxa such as Solorina crocea and Cladonia macroceras have persisted across decades at these southern margins, but historical records also warn of potential local extinctions: Alectoria ochroleuca, collected during the Renaissance by the naturalist Ulisse Aldrovandi, has not been confirmed by recent surveys.

Most cold-adapted species reported in the study were collected close to mountain summits, a fact with sobering implications. Summit populations have little room to move upward as temperatures rise, which limits their ability to track ongoing climate warming and suggests a substantial extinction debt. Even small future climatic shifts could precipitate local losses at the southern margins of their ranges, meaning that the very populations that make the Northern Apennines biogeographically significant are also among the most vulnerable. The researchers argue that this makes intensified exploration of potentially threatened lichen biota in mountain areas an urgent priority, since species may disappear before their distributions are fully documented.

The study also delivered taxonomic surprises. Notable examples include recently described species such as Lecanora albula and Lecanora vocontia, both recorded from a few localities in the Western Alps; Leprocaulon calcicola, previously known only from England and southern France; Metamelanea umbonata, described from Switzerland and also reported from Scandinavia; Ramalina europaea, apparently widespread in central Europe; and Verrucaria hakulinenii, previously known only from Finland. Other records involve re-evaluated taxa whose distributions were insufficiently known, such as Aspicilia spermatomanes, often confused with other species, and Verrucaria anziana, long treated as a synonym of Verrucaria latebrosa. Phaeophyscia erythrocardia, a first report from the Alps, was previously known from North America and the north-west Caucasus.

Cryptic diversity emerged as a recurring theme. The distribution of Parmelia ernstiae remains poorly understood because historical records may be hidden under those of the broader Parmelia saxatilis complex, and the same applies to Parmelia pinnatifida, a cryptic species often confused with Parmelia omphalodes. Enigmatic life-history traits are exemplified by Cladonia luteoalba, which is thought to begin its life cycle as a parasite on species of the Cladonia coccifera group. The researchers emphasize that accurate identification in such cases required an integrative approach combining morphology, secondary chemistry, and molecular data, and they recommend broader molecular sampling across the region to test hypotheses of cryptic diversity and refine phylogeographical inferences.

New records were associated with a range of well-defined substrates and microhabitats, including calcareous outcrops, shaded siliceous cliffs, old-growth montane forests, and anthropogenic stone structures. Fine-scale habitat heterogeneity, along with microclimatic variables such as humidity, insolation, and snow cover, emerged repeatedly as key determinants of local occurrence, helping to explain the coexistence of thermophilous and cryophilous taxa across short distances. These ecological patterns provide a rationale for prioritizing similar microhabitats in future surveys and underline how much of lichen diversity depends on habitats that are easily overlooked or degraded.

Several of the newly recorded taxa are of conservation concern at regional or national levels, and the discovery of small, isolated populations highlights the need for targeted measures, including protection of critical substrates and microhabitats from quarrying, inappropriate afforestation, and recreational disturbance. The researchers recommend that newly documented localities be incorporated into regional monitoring schemes and red-list assessments, and that voucher specimens be deposited in accessible herbaria to facilitate future re-examination. Longitudinal monitoring at selected sites will be essential to clarify population trends and assess the impacts of climate change and land-use shifts.

Beyond its immediate findings, the study underscores the enduring value of herbaria as repositories of primary biodiversity data: critical re-examination of deposited material in the light of current taxonomic knowledge yielded numerous new regional records that no amount of new fieldwork could have replaced. At the same time, the findings stress the importance of sustained field exploration to keep species lists and distributional knowledge up to date in the face of accelerating environmental change. Such primary data are fundamental for conservation planning, for taxonomic progress, and for parameterizing forecasting models that can improve predictive power.

The 518 occurrences and 288 taxa reported here substantially advance floristic knowledge of lichens in the Alps and the Northern Apennines, demonstrating that systematic field surveys, combined with integrative taxonomic methods and critical herbarium revision, remain indispensable for documenting mountain biodiversity. The new records have direct implications for biogeography, taxonomy, and conservation, and they identify clear priorities for future work: intensified exploration of under-surveyed sectors, expanded molecular sampling, and the integration of new data into regional databases and conservation assessments. As climate change accelerates in the world’s mountains, the race to document their smallest inhabitants has never mattered more.

Subject of Research: New lichen records from the Italian Alps and Northern Apennines

Article Title: Exploring the lichen biota of Italy: New records from the Italian Alps and Northern Apennines

Article References: Pistocchi, C., Gheza, G., Di Nuzzo, L., Francesconi, L., Girlanda, S., Hafellner, J., Kray, R., Mayrhofer, H., Nimis, P. L., Thüs, H., & Nascimbene, J. (2026). Exploring the lichen biota of Italy: New records from the Italian Alps and Northern Apennines. MycoKeys, 138, 237-247. https://doi.org/10.3897/mycokeys.138.197797

Image Credits: AI Generated

DOI: 10.3897/mycokeys.138.197797

Keywords: lichens, Italian Alps, Northern Apennines, biodiversity, climate change, herbaria, biogeography, conservation, taxonomic revision, molecular sequencing, arctic-boreal species, mountain ecology