Within the framework of ongoing updates to the Italian flora, this paper presents the results of floristic research conducted on the Tifatini and Trebulani Mountains, two limestone hilly-mountain systems in southern Italy. The vascular flora of the study area is largely unknown, with most of the available data dating back to the 19 th and early 20 th centuries. Data were collected through field surveys carried out between 2015 and 2023, primarily during the scientific excursion of the Working Group for Floristics, Systematics and Evolution of the Italian Botanical Society held in 2017. An opportunistic approach was adopted for floristic sampling; it was performed on 22 sites considered to be representative of the local environmental diversity in terms of physiography, climate, soil, elevation, and land use. The research led to taxonomic identification of 3,987 herbarium specimens, 2,623 of which were collected on the Tifatini Mountains and 1,364 on the Trebulani Mountains. Overall, 706 species and subspecies (including five hybrids) belonging to 121 families were identified. The total floristic list included 18 endemic species to Italy, 42 alien species, three cryptogenic species for the administrative region of Campania, and 47 species included in the IUCN Red List of the Italian flora. In the Tifatini area 591, species have been identified (nine endemics, 40 aliens, three cryptogenics, and 33 included in the IUCN Red List), whereas 369 species have been recorded in the Trebulani area (14 endemics, eight aliens, no cryptogenics, and 33 from the IUCN Red List). Six new species have been detected for the first time and five confirmed for the flora of Campania. The data collected during this survey underscores the importance of a collaborative approach among botanists for assessing the conservation status of the flora of the investigated territories, while also highlighting the occurrence of taxonomically critical groups requiring further investigation.

Based on the evaluation of 3,902 local floristic references published between 2005 and 2025, an update to the floristic knowledge map of Italy is presented. To measure the progress in floristic knowledge across Italy’s administrative regions, the ‘Index of Floristic Knowledge Advancement’ (IFA) is proposed here. This index categorizes regions based on the proportion of potential improvement that has actually been achieved. Results showed an improvement in knowledge, most notably for Northern and Central Italy. Emilia-Romagna emerged as the most comprehensively documented region with the highest IFA value (0.81), followed by Lombardia (0.60), Friuli-Venezia Giulia (0.54), Trentino-Alto Adige and Veneto (0.53). In central Italy, Lazio (0.50), Sardegna (0.45) and Toscana (0.36) registered the highest scores. Over the past twenty years, 453 specific and subspecific taxa have been described from the Italian territory, the majority of which (443) are Italian endemics. Hieracium is the most represented genus (147 taxa). The marked progress documented is likely due to the accelerated impact of coordinated scientific projects, citizen science programs, the development of digital databases, and an increased focus on taxonomic research.

The study of a country's flora is an open-ended work influenced by environmental changes, advances in taxonomical research, and the development of new data collection methods. In Italy, floristic research has evolved from early botanical records to digital databases allowing real-time updates. This study, conducted within the Italian Botanical Society, aimed at verifying, updating and expanding knowledge on species with uncertain, extinct, or excluded status. Starting in 2021, researchers from all regions of Italy collaborated to review literature, herbarium specimens, and field data. Their efforts culminated in 839 regional-level assessments of 628 taxa, leading to 276 changes in regional status and 25 at the national level. These updates are of great significance for nature conservation efforts by confirming species presence in some regions while verifying extinctions, particularly in fragile aquatic habitats. This research also underscores the importance of botanical collections and historical records to reconstruct the history, dynamics, and current distribution of plant species, and addresses challenges such as limited access to the collections. This study is not only a milestone in Italian floristics but also provides a replicable methodology for updating national floras globally.

In this contribution, new data concerning the distribution of vascular flora alien to Italy are presented. It includes new records, exclusions, and status changes from casual to naturalized or invasive for Italy or for Italian administrative regions for taxa in the genera Bidens, Ceratochloa, Chamaeiris, Cylindropuntia, Cyperus, Euphorbia, Freesia, Glinus, Hydrocotyle, Lagunaria, Megathyrsus, Myriophyllum, Opuntia, Schinus, Sparaxis, Sporobolus, Talinum, and Tradescantia. Nomenclatural and distribution updates, published elsewhere, and corrections are provided as Suppl. material.

Identifying areas susceptible to invasion by an alien species is a strategy of prevention. We used national herbaria and global databases to assess the invasion trends of the two aquatic invasive species Ludwigia hexapetala and Ludwigia peploidessubsp. montevidensis in Italy. We defined the invasion status with invasions curves and predicted potentially suitable areas with Species Distribution Models based on WorldClim variables and the human footprint index. Low seasonal variation in temperature and precipitation, temperature ≥ 20 °C in the warmest, driest and wettest periods of the year and precipitation in the coldest period are the bioclimatic factors that most account for the potential distribution of the two species. The human footprint has lower relative importance than bioclimatic variables. All Italian peninsula appears as a suitable bioclimatic environment for the invasion of the two Ludwigia species, except the Alps and the highest peaks in the Apennine. Based on the current distribution of the species in Italy and the mostly densely invaded areas globally, the agricultural land surrounding the current invaded areas and along the Italian coasts is the most vulnerable to the invasion. Considering the trend of the invasion curves, which have been sharply rising for the latest decades, there are reasons to expect that the alien Ludwigia species will continue their expansion, if no timely and effective actions are taken. Informative campaigns, accurate monitoring and prompt management are fundamental preventive tools in areas predicted as vulnerable to invasion by this study.

Archaeological areas often become hotspots for biodiversity and refugia for plant species. The management activity of a site permits the conservation of natural habitats. This first contribution to the floristic assessment of an Iranian archaeological site, aims to preserve its natural values. The Pasargadae World Heritage Site (sixth century BC) located at the border between the Zagros mountains and the Irano-Turanian region, showed a richness of 244 species, belonging to 38 families and 163 genera. The most represented families are Asteraceae (56), Poaceae (34) and Fabaceae (22). Herbaceous species represented 90% of the flora [therophytes (42%), hemicryptophytes (39%) and geophytes (9%)]. Asiatic, Irano-Turanian and Mediterranean species are the most recurrent species with a high component of endemic ones. Astragalus ghashghaicus, Taraxacum plicatulum, Acantholimon serotinum and Linaria farsensis were among the more interesting floristic elements. The comparison with past data, even if limited in quantity, indicated a good floristic conservation status. This research also showed the need to deepen our knowledge of the taxonomic features of this Iranian flora, sometimes still resulting in an ambiguous or unresolved status. The collected floristic data will help in elaborating management protocols, to enhance the cultural and natural value of the site.

In archaeological sites, plants can be a risk for monument conservation. However, in these sites, a refugium for plant biodiversity is often detected, such as in the UNESCO site Etruscan necropolis of “Monterozzi” in Tarquinia, which still holds a Special Protection Area for bats. In this site, we previously evaluated the positive and negative effects of vascular plants on the conservation of the hypogeal tombs. To contribute in assessing the role of archaeological sites in supporting plant diversity and interpreting its bioindication values for nature conservation, we analyse in this relevant place the floristic interest and richness and the plant communities growing on tumuli, trampled, and less disturbed areas. The results revealed the presence of several plants with high naturalistic interest, such as the community’s representative of synanthropic and natural Mediterranean grasslands, which arise both from the present and the past uses of the area. The high naturalistic values of the site are also assessed, considering its remarkable richness of species/area compared with the well-known archaeological sites of Rome. These findings further indicate that plant diversity needs to be considered in planning management activities in archaeological sites to also protect their natural values.

We analysed the invasion history of two North American macrophytes (Elodea canadensis and E. nuttallii) in Italy, through an accurate census of all available herbarium and field records, dating between 1850 and 2019, and a rich literature collection describing the initial introduction and naturalisation phase that supports the results obtained by the occurrence records. Elodea canadensis arrived in Italy before 1866 and had two invasion phases, between the 1890s and 1920s and between the 1990s and 2000s; E. nuttallii, probably arrived in the 1970s, started invading in 2000 and the invasion is still ongoing. Botanical gardens and fish farming played a crucial role in dispersal and naturalisation of both species. The current invasion range of both species is centred in northern Italy, with scattered occurrences of E. canadensis in central and southern regions. River Po represents a dispersal barrier to the Mediterranean region and a strategic monitoring site to prevent the invasion in the peninsula. The study detects differences in the niches of the two species during the introduction and naturalisation phase and a habitat switch occurred after 1980 in E. canadensis and after 2000 in E. nuttallii, during their expansion phases. For E. canadensis the switch corresponds to the second invasion round. Further research can clarify whether the second invasion round is due to confusion of the recently introduced E. nuttallii with E. canadensis, to a cryptic introduction of a new genotype, to post-introduction evolution, or just to an increased scientific interest in biological invasions.

In this contribution, new data concerning the distribution of vascular flora alien to Italy are presented. It includes new records, confirmations, exclusions, and status changes for Italy or for Italian administrative regions. Nomenclatural and distribution updates published elsewhere are provided as Suppl. material 1.

The Mediterranean basin has been a refugium for relict plant taxa and native laurophyllic forests. The Latium coasts and, especially, the Antica Lavinium site, host relict forest communities, whose natural importance is enriched by their cultural value. Here, we aim at investigating the ecological framework, cultural and historical values, and management over time, of relict communities that have Laurus nobilis and Celtis australis as their priority habitats. To achieve this, we performed vegetation surveys and we conducted statistical analyses (PCA, NMDS). Among the 45 vegetation surveys, 25 were characterized by the two target species. The PCA analysis highlighted how the L. nobilis formations and the mixed formations with C. australis present some differences but are not sufficient to describe different coenosis. The comparison among similar forests in central and southern Italy confirmed the wide coenological amplitude of L. nobilis with respect to other laurophyllic species. Antica Lavinium has an overall good preservation of laurel forest formations, but also of mixed formation with C. australis. In the area, historical, cultural, and natural characteristics mutually contributed to the development of human civilizations and plant communities, highlighting their deep linkage.

Urban rivers may perform important ecological roles and provide many ecosystem services, especially in urban contexts. Considering this, River Contracts were officially introduced in 2000, during the Second Forum of the World Water Council, as participative agreements aimed at managing the complexity of fluvial ecosystems. Collecting data on fluvial and riparian biodiversity, establishing ecological relationships among biological components, and evaluating their resistance and resilience to anthropic impacts are needed to assess the ecological sustainability of the anthropic actions. Here, we provide a review of literature and regulation on River Contracts, and a methodological contribution to the evaluation of different environmental components, their ecological connections, and the role of anthropic impacts. To address the aim, we performed a critical analysis of the existing data on the Tiber River close to Rome. We used the information to identify the actions that should be included in the Tiber River Contract to improve its natural value and its potential ecosystem services. Several areas emerged where information was lacking such as the human impact on these ecosystems. Data highlight the disappearance of rare Mediterranean species and of those linked to wetland habitats, as well as an increase in alien species and species typical of disturbed areas. Further research on biodiversity and management is required to support nature conservation.

Invasive alien plants are a major threat to biodiversity and they contribute to the unfavourable conservation status of habitats of interest to the European Community. In order to favour implementation of European Union Regulation no. 1143/2014 on invasive alien species, the Italian Society of Vegetation Science carried out a large survey led by a task force of 49 contributors with expertise in vegetation across all the Italian administrative regions. The survey summed up the knowledge on impact mechanisms of invasive alien plants in Italy and their outcomes on plant communities and the EU habitats of Community Interest, in accordance with Directive no. 92/43/EEC. The survey covered 241 alien plant species reported as having deleterious ecological impacts. The data collected illustrate the current state of the art, highlight the main gaps in knowledge, and suggest topics to be further investigated. In particular, the survey underlined competition as being the main mechanism of ecological impact on plant communities and Natura 2000 habitats. Of the 241 species, only Ailanthus altissima was found to exert an ecological impact on plant communities and Natura 2000 habitats in all Italian regions; while a further 20 species impact up to ten out of the 20 Italian administrative regions. Our data indicate that 84 out of 132 Natura 2000 Habitats (64%) are subjected to some degree of impact by invasive alien plants. Freshwater habitats and natural and semi-natural grassland formations were impacted by the highest number of alien species, followed by coastal sand dunes and inland dunes, and forests. Although not exhaustive, this research is the first example of nationwide evaluation of the ecological impacts of invasive alien plants on plant communities and Natura 2000 Habitats.

This study provides a first step toward the knowledge of the alien-dominated and co-dominated plant communities present in Italy. The first ever checklist of the alien phytocoenoses described or reported in literature for the Italian territory has been compiled, produced by data-mining in national and local thematic literature. The resulting vegetation-type draft-list has been checked in the light of the most recent syntaxonomic documentation and updated with regards to syntaxonomy and nomenclature, with special reference to the frame proposed in the Italian Vegetation Prodrome. The list includes 27 vascular and one bryophyte vegetation classes, hosting 194 low rank alien-dominated syntaxa. The different vegetation types detected for each syntaxonomic class and macro-vegetation group, defined by physiognomical and ecological attributes, are discussed.

The perception that the turnover of 45S rDNA site number in plants is highly dynamic pervades the literature on rDNA evolution. However, most reported evidences come from the study of polyploid systems and from crop species subjected to intense agronomic selection. In sharp contrast with polyploids, the evolutionary patterns of rDNA loci number in predominantly diploid lineages have received less attention. Most studies on rDNA loci changes lack explicit temporal frames, and hence their dynamics could not be assessed. Here, we assess the temporal patterns of rDNA site evolution in Cistus, an entirely diploid lineage. We assessed the number and chromosomal position of 45S rDNA loci in Cistus species using fluorescence in situ hybridization (FISH) and Ag-nucleolus organizing regions (Ag-NOR) staining. Maximum likelihood and maximum parsimony reconstructions of the ancestral state of the 45S rDNA locus number were inferred onto a dated phylogeny. 45S rDNA locus number in Cistus ranged from one to four. Maximum likelihood and maximum parsimony reconstructions suggested that the two-loci state was the ancestral condition in Cistaceae, including the sister genera Tuberaria and Cistus. The most likely basal number of rDNA loci (two) has been maintained from the hypothesized ancient splitting events between Fumana and the remaining Cistaceae lineages in the Oligocene to most of the recent clades of Cistus diversified in the Middle Pleistocene. Our results support the view that evolutionary stasis regarding the number of 45S rDNA loci have been prevalent in several Cistus lineages and close relatives along their evolutionary history. It is suggested that conservation in rDNA site number likely occurred along more than 25 Mya of plant evolution, leading support to hypothesize that rDNA stasis in site number may have been neglected and underestimated in plant evolution at the diploid level. (C) 2016 The Linnean Society of London.