Background and aims – We present the first comprehensive checklist of North American gypsophiles (plants restricted or nearly restricted to gypsum soils) to encourage the further exploration of gypsum exposures, promote systematic studies, and raise awareness about the potential need of conservation measures for these ecologically and evolutionary unique species. Material and methods – The checklist was based on a historical literature search, herbarium specimens, and fieldwork. We estimated an Aridity Index for the gypsum localities of all occurrences, taxa description over time, growth form, generic diversity within families as compared to global patterns, and conservation status. Key results – We recognize 287 taxa as gypsophiles, which occur from Montana, USA to southern Mexico, including 282 angiosperm taxa, 3 ferns, one gymnosperm, and one lycophyte. Herbaria and literature review retrieved 3,528 records for gypsophile taxa. The gypsum localities from these records were classified from arid to humid, with most being arid or semi-arid. The most diverse families were Asteraceae (77 taxa), Brassicaceae (14), Loasaceae/Nyctaginaceae (13), and Cactaceae/Namaceae (11). The most diverse genera were Mentzelia / Nama / Nerisyrenia (11), Phacelia / Pinguicula (9), and Drymaria / Gaillardia (8). Most gypsophile taxa were classified as perennial herbs (207) or shrubs (38), but annual herbs (17) and one tree-like species were also recorded. Only 45 taxa were found to be protected at any level. Conclusion – North America has the most diverse gypsophile flora yet known globally. It is composed of a wide phylogenetic diversity including many growth forms and biomes, ranging from xeric shrublands to grasslands, coniferous forests, and tropical forests. Few gypsophile taxa have legal protections, and additional studies are clearly needed to assess their conservation risk. This first comprehensive checklist, while subject to change, will serve as a foundation for future research.
Background and aims – Alternanthera is one of the largest genera in Amaranthaceae, with the primary distribution in the Americas. The identification of some species, including those occurring as alien noxious weeds in the Old World, is challenging because of unstable taxonomy and nomenclature. In addition, their means and history of introduction remain poorly understood. Here, we revise the alien species of Alternanthera in the Arabian Peninsula, providing notes on their morphology, distribution, nomenclature, and dispersal facilities. Material and methods – We analysed type specimens, vegetative, floral and fruit characters, introduction history, and occurrences of four species of the genus in the Arabian Peninsula. Key results – Alternanthera ficoidea is reported for the first time from the Arabian Peninsula, and A. sessilis is newly recorded in the United Arab Emirates. The history and means of the species introduction are discussed. The turbulent nomenclatural history of A. ficoidea and A. tenella is reviewed to resolve the current confusion in their European records, and we propose that the latter name should unambiguously be considered as a synonym of A. ficoidea . The original spelling of Telanthera “ bettzickiana ” and A. “ bettzickiana ” are researched, and the species epithet is corrected to “ bettzichiana ”. A lectotype is designated for A. achyranthes , the generic type of Alternanthera . Detailed morphological descriptions of the propagules of Alternanthera are provided, and their role in the dispersal process are discussed. Conclusion – We noted a recent expansion of Alternanthera ficoidea , A. pungens , and A. sessilis in natural and anthropogenically disturbed plant communities of the Arabian Peninsula, especially across the coastlines of the Arabian Sea and Red Sea, and in foothills of the Sarawat Mountains. Their spread occurs through both vegetative and sexual means of dispersal. Our examination of morphological characters reveals a distinct role of the perianth and pericarp in the propagule dispersal of these species.
The article on the environmental drivers of the distribution of Ragala ucuquirana-branca (Sapotaceae) across the Amazon Basin, published in Plant Ecology and Evolution 159(2), contained an unfortunate error (Cunha et al. 2026). Earlier versions of Figs 3, 5, 6, and 7, prepared before the manuscript was revised during peer review, were inadvertently published instead of the revised versions. As a result, these figures do not fully match the text and figure captions of the article. The correct figures and their captions are presented here.
Background and aims – Integrating landscape information with genetic data offers critical insights for biodiversity conservation and management. The Gran Chaco region, one of the most biodiverse and threatened subtropical woodlands, features a highly heterogeneous landscape largely shaped by river dynamics. This study focuses on Aspidosperma quebracho-blanco , a dominant tree species in this region with ecological, commercial, medical, and conservation significance, to investigate the interactions among population genetics, landscape features, and climatic factors. Material and methods – To assess if watersheds influence the spatial distribution of genetic variability in A. quebracho-blanco , we conducted analyses of genetic variability and structure among watersheds. Based on AFLP data, we applied horizontal interpolation analysis, Mantel test, and Barrier software to identify potential barriers to gene flow among populations and compared these with topographic and hydrographic features across the Argentinian Chaco. Finally, we used Principal Component Analysis (PCA) to evaluate the influence of environmental variables on genetic diversity. Key results – Our results reveal that genetic variability is spatially structured at the regional scale. Eight potential barriers to gene flow were identified, primarily corresponding to major river systems and orographic features. PCA indicated that elevation and climate likely influence population genetic patterns. Conclusion – The observed associations among genetic structure, landscape heterogeneity, and climate provide essential insights for the management, conservation, and ecological restoration of A. quebracho-blanco in the Gran Chaco region. For in situ conservation, it is recommended that each sampled population be managed independently. In contrast, for restoration actions and ex situ conservation, management is recommended from a watershed-based perspective.
Background and aims – The Philippine archipelago harbours the world’s greatest diversity of flowering plants, yet it is identified as a global plant diversity darkspot where much of this diversity remains poorly documented and inadequately sampled. To address this knowledge gap, extensive botanical explorations have been conducted, leading to the discovery of three new Begonia species from Panay and Mindanao Islands, which are described and illustrated herein. Material and methods – All morphological descriptions and measurements are based on recently collected living and herbarium specimens. The new species are included in a phylogenetic analysis based on noncoding plastid regions (ndhA intron, ndhF-rpl32 spacer, and rpl32-trnL spacer) and the nuclear internal transcribed spacer (nrITS) region from the assembled plastome and nuclear ribosomal DNA sequences. Key results – The newly described species from Mindanao (Begonia absiana sp. nov. and B. amorosoana sp. nov.) exhibit close morphological similarities to B. acuminatissima, while the novel species from Panay (B. panayica sp. nov.) shows affinity to B. biliranensis. The phylogenetic analyses confirmed the monophyly of B. sect. Baryandra but revealed significant cytonuclear discordance and unresolved relationships within the group. All three new species were placed in a well-supported clade, but their precise relationships remain uncertain, possibly reflecting rapid diversification. Conclusion – These findings underscore an urgent need to intensify botanical exploration and conservation efforts in the Philippines to protect these unique evolutionary lineages before their habitats are lost.
