The psyllid fauna of the Canary Islands is reviewed on the basis of recent field work on Tenerife, La Gomera, La Palma Gran Canaria and Lanzarote, as well as the examination of material deposited in several collections. Two new genera and 16 new species are described: Drepanoza Bastin, Burckhardt & Ouvrard gen. nov., Percyella Bastin, Burckhardt & Ouvrard gen. nov., Agonoscena atlantica Bastin, Burckhardt & Ouvrard sp. nov., A. sinuata Bastin, Burckhardt & Ouvrard sp. nov., Arytaina meridionalis Bastin, Burckhardt & Ouvrard sp. nov., Cacopsylla crenulatae Bastin, Burckhardt & Ouvrard sp. nov., C. falcicauda Bastin, Burckhardt & Ouvrard sp. nov., Diaphorina gonzalezi Bastin, Burckhardt & Ouvrard sp. nov., Drepanoza canariensis Bastin, Burckhardt & Ouvrard sp. nov., D. fruticulosi Bastin, Burckhardt & Ouvrard sp. nov., D. molinai Bastin, Burckhardt & Ouvrard sp. nov., Euphyllura confusa Bastin, Burckhardt & Ouvrard sp. nov., Percyella benahorita Bastin, Burckhardt & Ouvrard sp. nov., P. canari Bastin, Burckhardt & Ouvrard sp. nov., P. gomerita Bastin, Burckhardt & Ouvrard sp. nov., P. guanche Bastin, Burckhardt & Ouvrard sp. nov., Strophingia canariensis Bastin, Burckhardt & Ouvrard sp. nov. and S. paligera Bastin, Burckhardt & Ouvrard sp. nov. Arytaina insularis Loginova, 1976, stat. nov. is elevated from a subspecies of A. devia Loginova, 1976 to species rank. Five new combinations are proposed: Drepanoza fernandesi (Aguiar, 2001) comb. nov., D. lienhardi (Burckhardt, 1981) comb. nov., D. montanetana (Aguiar, 2001) comb. nov., D. pittospori (Aguiar, 2001) comb. nov. and Lauritrioza laurisilvae (Hodkinson, 1990) comb. nov., all transferred from Trioza. The hitherto unknown last-instar immatures are described for Megadicrania tecticeps Loginova, 1976, Cacopsylla atlantica (Loginova, 1976) and Lauritrioza laurisilvae (Hodkinson, 1990). We also report Agonoscena targionii (Lichtenstein, 1874) for the first time from the Canary Islands. Our review increases the number of known psyllid taxa from the Canary Islands to 24 genera and 62 species (one of which remains undescribed). Endemism, host plant relationships and biogeographic patterns are discussed. Keys for the identification of adults and immatures are provided, as well as information on host plants, distribution and predators.

Aim: Understanding the historical and contemporaneous drivers of invasion success in island systems can decisively contribute to identifying sources and pathways that are more likely to give rise to new invaders. Based on a floristic‐driven approach, we aimed at determining the origins of the invasive alien flora of the Canary Islands and shedding light in the mechanisms shaping their distribution within the archipelago.Location: Canary Islands.Taxon: Vascular plants.Methods: An updated checklist of the invasive alien flora of the Canary Islands was assembled along with complementary information related to the native biogeographical regions, stage of invasiveness and dates of naturalization. Statistical models were employed to describe differences in the number of species over space and time. We also used multivariate techniques to evaluate competing hypotheses related to the mechanisms driving invasive floristic composition within the archipelago.Results: We provided a list of 149 alien plant species with a certain degree of invasiveness. The greatest number of invasive species originated from the Neotropics followed by the Cape Region, tropical Africa and the Mediterranean Basin. We observed a slow but steady increase in numbers of invasive species until the 1950s, followed by a stronger rise thereafter. In order to explain composition dissimilarity of the invasive flora among islands, a climatic matching hypothesis was fully supported, with geographic isolation and contemporary human‐mediated connectivity hypotheses receiving less and null support respectively.Main Conclusions: We showed that the Neotropical region is the main source of plant invasions to the Canary Islands, outnumbering those from other regions with a Mediterranean‐type bioclimate. The assembly of the invasive flora within the archipelago appears to be driven primarily by climate, but with geographic distance also playing a role. This study calls for archipelago‐dependent assessments of the underlying mechanisms that contribute to plant invasion success within insular systems.

A robust phylogenetic framework, in terms of extensive geographical and taxonomic sampling, well-resolved species relationships and high certainty of tree topologies and branch length estimations, is critical in the study of macroevolutionary patterns. Whereas Sanger sequencing-based methods usually recover insufficient phylogenetic signal, especially in recently diversified lineages, reduced-representation sequencing methods tend to provide well-supported phylogenetic relationships, but usually entail remarkable bioinformatic challenges due to the inherent trade-off between the number of SNPs and the magnitude of associated error rates. The genus Helianthemum (Cistaceae) is a species-rich and taxonomically complex Palearctic group of plants that diversified mainly since the Upper Miocene. It is a challenging case study since previous attempts using Sanger sequencing were unable to resolve the intrageneric phylogenetic relationships. Aiming to obtain a robust phylogenetic reconstruction based on genotyping-by-sequencing (GBS), we established a rigorous methodological workflow in which we i) explored how variable settings during dataset assembly have an impact on error rates and on the degree of resolution under concatenation and coalescent approaches, ii) assessed the effect of two extreme parameter configurations (minimizing error rates vs. maximizing phylogenetic resolution) on tree topology and branch lengths, and iii) evaluated the effects of these two configurations on estimates of divergence times and diversification rates. Our analyses produced highly supported topologically congruent phylogenetic trees for both configurations. However, minimizing error rates did produce more reliable branch lengths, critically affecting the accuracy of downstream analyses (i.e. divergence times and diversification rates). In addition to recommending a revision of intrageneric systematics, our results enabled us to identify three highly diversified lineages in Helianthemum in contrasting geographical areas and ecological conditions, which started radiating in the Upper Miocene.

Recent field work in Gran Canaria and Tenerife (Canary Islands, Spain) yielded records for 30 alien taxa of Cactaceae that had not been reported before, either from the whole area, or from one of the islands. Out of these, 17 are considered locally naturalised and/or potentially invasive: Cylindropuntia bigelovii, C. fulgida, C. pallida, C. prolifera, C. tunicata, Echinocereus rigidissimus, Haageocereus kagenekii, Hylocereus triangularis, Opuntia basilaris, O. elatior, O. ficus-indica × O. tomentosa, O. macrocentra, O. microdasys, O. pilifera, Oreocereus pseudofossulatus, Tephrocactus articulatus and Trichocereus huascha. The same applies to a rather characteristic form of O. ficus-indica that sometimes is referred to as f. amyclaea (syn.: O. megacantha). The presence of Opuntia monacantha and O. robusta, two species with a dubious status in the Canary Islands, is confirmed. Ten further taxa are considered casuals, often relics of cultivation. All taxa are illustrated, and for the naturalised and/or potentially invasive taxa additional information is provided. Two new combinations are proposed for Cylindropuntia fulgida f. mamillata and Tephrocactus articulatus f. papyracanthus. Bei jüngsten Feldstudien auf Gran Canaria und Teneriffa (Kanarische Inseln, Spanien) wurden 30 nicht indigene Taxa von Cactaceae nachgewiesen, die bisher weder vom Gesamtarchipel noch von einer der beiden Inseln gemeldet waren. Von diesen werden 17 als lokal eingebürgert und / oder potenziell invasiv angesehen: Cylindropuntia bigelovii, C. fulgida, C. pallida, C. prolifera, C. tunicata, Echinocereus rigidissimus, Haageocereus kagenekii, Hylocereus triangularis, Opuntia basilaris, O. elatior, O. ficus-indica × O. tomentosa, O. macrocentra, O. microdasys, O. pilifera, Oreocereus pseudofossulatus, Tephrocactus articulatus und Trichocereus huascha. Das Gleiche gilt für eine sehr charakteristische Form von O. ficus-indica, die manchmal als f. amyclaea (syn.: O. megacantha) bezeichnet wird. Zehn weitere Taxa, oft Anbaurelikte, gelten als nicht eingebürgert. Alle Taxa sind abgebildet, zu den eingebürgerten und / oder potenziell invasiven Taxa erfolgen weitere Informationen. Zwei neue Kombinationen werden vorgeschlagen: Cylindropuntia fulgida f. mamillata und Tephrocactus articulatus f. papyracanthus.

Whether species extinctions have accelerated during the Anthropocene and the extent to which certain species are more susceptible to extinction due to their ecological preferences and intrinsic biological traits are among the most pressing questions in conservation biology. Assessing extinction rates is, however, challenging, as best exemplified by the phenomenon of ‘ dark extinctions ’: the loss of species that disappear before they are even formally described. These issues are particularly problematic in oceanic islands, where species exhibit high rates of endemism and unique biological traits but are also among the most vulnerable to extinction. Here, we document plant species extinctions since Linnaeus' Species Plantarum in Macaronesia, a biogeographic region comprised of five hyperdiverse oceanic archipelagos, and identify the key drivers behind these extinctions. We compiled 168 records covering 126 taxa, identifying 13 global and 155 local extinction events. Significantly higher extinction rates were observed compared to the expected global background rate. We uncovered differentiated extinction patterns along altitudinal gradients, highlighting a recent coastal hotspot linked to socioeconomic changes in Macaronesian archipelagos from the 1960s onwards. Key factors influencing extinction patterns include island age, elevation, introduced herbivorous mammals, and human population size. Trait‐based analyses across the floras of the Azores and Canary Islands revealed that endemicity, pollination by vertebrates, nitrogen‐fixing capacity, woodiness, and zoochory consistently tended to increase extinction risk. Our findings emphasize the critical role of geography and biological traits, alongside anthropogenic impacts, in shaping extinction dynamics on oceanic islands. Enhancing our knowledge of life‐history traits within island floras is crucial for accurately predicting and mitigating future extinction risks, underscoring the urgent need for comprehensive biodiversity assessments in island ecosystems.