Science Enabled by Specimen Data

Rouichi, S., M. E. Ghanem, and M. Amri. 2024. In‐situ and ex‐situ conservation priorities and distribution of lentil wild relatives under climate change: A modelling approach. Journal of Applied Ecology. https://doi.org/10.1111/1365-2664.14842

Abstract Lentil wild relatives are an important source of desirable traits that can be used for improving the productivity and resilience of cultivated lentil. Yet, our understanding of their habitat suitability and associated environmental factors remains limited. This study aimed to (i) assess climate change's impact on the potential distribution of six wild lentil species (Lens culinaris subsp. orientalis, L. culinaris subsp. tomentosus, L. culinaris subsp. odemensis, Lens ervoides, Lens lamotte and Lens nigricans) under various climate scenarios and (ii) assess their risk of extinction and determine their in‐situ and ex‐situ conservation status. We used a species distribution modelling approach with MaxEnt to assess the present and future potential distribution of wild lentil species. Extinction risk was evaluated based on International Union of Conservation of Nature criterion B, and the conservation status was assessed using the GapAnalysis method. The precipitation of the coldest quarter (bio19) and the minimum temperature of the coldest month (bio6) were found as the most important variables influencing the distribution of wild lentil species. Final Conservation Score (FCS) ranged from 17.85 and 37.55, highlighting three wild lentil species (L. ervoides, L. nigricans, and L. culinaris subsp. tomentosus) with high priority for conservation and medium priority for the remaining species. L. culinaris subsp. tomentosus is categorized as a vulnerable species, while the other five species are of least concern or near threatened. Synthesis and applications: This study underscores the urgent need for policy development to safeguard the diversity of lentil wild relatives in the face of climate change. The identified vulnerability of Lens culinaris subsp. tomentosus, among others, needs prompt and proactive conservation actions. Key management practices include the establishment and expansion of protected areas, habitat restoration, and the promotion of sustainable land use practices. The integration of effective in‐situ and ex‐situ conservation strategies, along with ecological management practices, is essential. These measures, not only, enhance biodiversity conservation but also improve the resilience of agricultural ecosystems. Such an approach is pivotal in shaping effective conservation management practices for lentil wild relatives, promoting a sustainable agricultural system and ensuring food security in an evolving climate scenario.

Hagelstam-Renshaw, C., J. J. Ringelberg, C. Sinou, W. Cardinal-McTeague, and A. Bruneau. 2024. Biome evolution in subfamily Cercidoideae (Leguminosae): a tropical arborescent clade with a relictual depauperate temperate lineage. Brazilian Journal of Botany 48. https://doi.org/10.1007/s40415-024-01058-z

Some plant lineages remain within the same biome over time (biome conservatism), whereas others seem to adapt more easily to new biomes. The c. 398 species (14 genera) of subfamily Cercidoideae (Leguminosae or Fabaceae) are found in many biomes around the world, particularly in the tropical regions of South America, Asia and Africa, and display a variety of growth forms (small trees, shrubs, lianas and herbaceous perennials). Species distribution maps derived from cleaned occurrence records were compiled and compared with existing biome maps and with the literature to assign species to biomes. Rainforest (144 species), succulent (44 species), savanna (36 species), and temperate (10 species) biomes were found to be important in describing the global distribution of Cercidoideae, with many species occurring in more than one biome. Two phylogenetically isolated species-poor temperate ( Cercis ) and succulent ( Adenolobus ) biome lineages are sister to two broadly distributed species-rich tropical clades. Ancestral state reconstructions on a time-calibrated phylogeny suggest biome shifts occurred throughout the evolutionary history of the subfamily, with shifts between the succulent and rainforest biomes, from the rainforest to savanna, from the succulent to savanna biome, and one early occurring shift into (or from) the temperate biome. Of the 26 inferred shifts in biome, three are closely associated with a shift from the ancestral tree/shrub growth form to a liana or herbaceous perennial habit. Only three of the 13 inferred transcontinental dispersal events are associated with biome shifts. Overall, we find that biome shifts tend to occur within the same continent and that dispersals to new continents tend to occur within the same biome, but that nonetheless the biome-conserved and biogeographically structured Cercidoideae have been able to adapt to different environments through time.

Ovcharova, N. V., M. M. Silantyeva, A. Vaganov, and A. A. Masanina. 2024. Invasion dynamics of Acer negundo L. in ribbon forests of the Altai Krai: ecological impacts and predictive habitat modeling. Altai State University. https://doi.org/10.5281/zenodo.14437657

This study examines the invasion dynamics of ash-leaved maple (box elder, Acer negundo L.) in the ribbon forests of Altai Krai, Russia, where it has become one of the dominant invasive species over the past thirty years. Originally introduced as an ornamental plant in the early 20th century, A. negundo has rapidly proliferated in lowland, steppe, and forest-steppe regions, significantly impacting local ecosystems. Our research analyzes the ecological and phytocoenotic conditions that facilitate A. negundo's invasion, focusing on its distribution across various ribbon pine forests in the region. Through geobotanical surveys and forest management record analysis, we reveal the species' prevalence in diverse forest types and its effects on biodiversity, tree growth, and community dynamics. Key findings indicate that A. negundo flourishes in disturbed habitats, where it aggressively competes with native flora, suppressing their growth and altering successional pathways. This leads to low-diversity communities increasingly dominated by the invasive species and highlights the exacerbating role of logging and land-use changes. Using predictive modeling techniques, we assessed habitat suitability for A. negundo across Eurasia, identifying temperature as the primary limiting factor for its distribution. The model achieved a high AUC value of 0.97, indicating strong reliability. These findings suggest a significant potential for A. negundo's range expansion throughout Altai Krai, especially in areas with reduced competition from native species. This research underscores the urgent need for effective management strategies to mitigate the effects of A. negundo in Altai Krai and similar regions.

Zhao, J., Z.-L. Liang, S.-L. Fang, R.-J. Li, C.-J. Huang, L.-B. Zhang, T. Robison, et al. 2025. Phylogenomics of Paragymnopteris (Cheilanthoideae, Pteridaceae): Insights from plastome, mitochondrial, and nuclear datasets. Molecular Phylogenetics and Evolution 204: 108253. https://doi.org/10.1016/j.ympev.2024.108253

Previous studies have shown that at least six genera of the Cheilanthoideae, a subfamily of the fern family Pteridaceae, may not be monophyletic. In these non-monophyletic genera, the Old-World genus Paragymnopteris including approximately five species have long been controversial. In this study, with an extensive taxon sampling of Paragymnopteris, we assembled 19 complete plastomes of all recognized Paragymnopteris species, plastomes of Pellaea (3 species) and Argyrochosma (1 species), as well as transcriptomes from Paragymnopteris (6 species) and Argyrochosma (1 species). We conducted a comprehensive and systematic phylogenomic analysis focusing on the contentious relationships among the genus of Paragymnopteris through 9 plastid makers, the plastomes, mitochondria, nuclear ribosomal cistron genomes, and single-copy nuclear genes. Moreover, we further combined distribution, ploidy, and morphological features to investigate the evolution of Paragymnopteris. The backbone of Paragymnopteris was resolved consistently in the nuclear and plastid phylogenies. Our major results include: (1) Paragymnopteris is not monophyletic including two fully supported clades; (2) confirming that Paragymnopteris delavayi var. intermedia is a close relative of P. delavayi instead of P. marantae var. marantae; (3) the chromosome base number may not be a stable trait which has previously been used as an important character to divide Paragymnopteris into two groups; and (4) gene flow or introgression might be the main reason for the gene trees conflict of Paragymnopteris, but both gene flow and ILS might simultaneously and/or cumulatively act on the conflict of core pellaeids. The robust phylogeny of Paragymnopteris presented here will help us for the future studies of the arid to semi-arid ferns of Cheilanthoideae at the evolutionary, physiological, developmental, and omics-based levels.

OLARIAGA, I., R. MÁRQUEZ-SANZ, S. P. GORJÓN, J. C. ZAMORA, and I. SALCEDO. 2024. Hymenochaete ametzii sp. nov. (Hymenochaetales, Basidiomycota), an endangered bark-dwelling species inhabiting old Quercus pyrenaica trees from the Iberian Peninsula. Phytotaxa 669: 194–210. https://doi.org/10.11646/phytotaxa.669.3.2

Bark-dwelling fungi represent a group of ecologically highly specialized organisms. This study deals with an undescribed species of Hymenochaete characterized by specifically inhabiting the bark of Pyrenean oak (Quercus pyrenaica), and producing effuse-reflexed basidiomata and mainly globose to subglobose basidiospores. Maximum Likelihood and Bayesian analyses of the nuclear ITS-LSU regions revealed that the sequences of H. ametzii form a monophyletic group with a low intraspecific variation and substantially different from closest taxa, further supporting its recognition as a species. The seven localities H. ametzii is known from are old forests with a long ecological continuity, containing large old Q. pyrenaica trees, and are located in the supramediterranean belt of the Mediterranean biogeographical region. Based on habitat availability and field counts of colonized trees, the global population of H. ametzii is estimated at 8,670 mature individuals. Considering that the traditional use of old Q. pyrenaica stands ceased several decades ago in the Iberian Peninsula, with a consequent decline in habitat quality and availability, it is concluded that H. ametzii is Endangered (EN) according to the IUCN criteria. Bark-dwelling fungi represent a group of ecologically highly specialized organisms. This study deals with an undescribed species of Hymenochaete characterized by specifically inhabiting the bark of Pyrenean oak (Quercus pyrenaica), and producing effuse-reflexed basidiomata and mainly globose to subglobose basidiospores. Maximum Likelihood and Bayesian analyses of the nuclear ITS-LSU regions revealed that the sequences of H. ametzii form a monophyletic group with a low intraspecific variation and substantially different from closest taxa, further supporting its recognition as a species. The seven localities H. ametzii is known from are old forests with a long ecological continuity, containing large old Q. pyrenaica trees, and are located in the supramediterranean belt of the Mediterranean biogeographical region. Based on habitat availability and field counts of colonized trees, the global population of H. ametzii is estimated at 8,670 mature individuals. Considering that the traditional use of old Q. pyrenaica stands ceased several decades ago in the Iberian Peninsula, with a consequent decline in habitat quality and availability, it is concluded that H. ametzii is Endangered (EN) according to the IUCN criteria.

Calleja-Satrustegui, A., A. Echeverría, I. Ariz, J. Peralta de Andrés, and E. M. González. 2024. Unlocking nature’s drought resilience: a focus on the parsimonious root phenotype and specialised root metabolism in wild Medicago populations. Plant and Soil. https://doi.org/10.1007/s11104-024-06943-w

Abstract  Background and aims Crop wild relatives, exposed to strong natural selection, exhibit effective tolerance traits against stresses. While an aggressive root proliferation phenotype has long been considered advantageous for a range of stresses, it appears to be counterproductive under drought due to its high metabolic cost. Recently, a parsimonious root phenotype, metabolically more efficient, has been suggested to be better adapted to semiarid environments, although it is not clear that this phenotype is a trait exhibited by crop wild relatives. Methods Firstly, we analysed the root phenotype and carbon metabolism in four Medicago crop wild relatives adapted to a semiarid environment and compared them with the cultivated M. truncatula Jemalong (A17). Secondly, we exposed the cultivated (probably the least adapted genotype to aridity) and the wild (the most common one in arid zones) M. truncatula genotypes to water deficit. The carbon metabolism response in different parts of their roots was analysed. Results A reduced carbon investment per unit of root length was a common trait in the four wild genotypes, indicative of an evolution towards a parsimonious root phenotype. During the water deficit experiment, the wild M. truncatula showed higher tolerance to drought, along with a superior ability of its taproot to partition sucrose and enhanced capacity of its fibrous roots to maintain sugar homeostasis. Conclusion A parsimonious root phenotype and the spatial specialization of root carbon metabolism represent two important drought tolerance traits. This work provides relevant findings to understand the response of Medicago species roots to water deficit.

Bradshaw, C. D., D. L. Hemming, T. Mona, W. Thurston, M. K. Seier, D. P. Hodson, J. W. Smith, et al. 2024. Transmission pathways for the stem rust pathogen into Central and East Asia and the role of the alternate host, barberry. Environmental Research Letters 19: 114097. https://doi.org/10.1088/1748-9326/ad7ee3

Abstract After many decades of effective control of stem rust caused by the Puccinia graminis f.sp. tritici, (hereafter Pgt) the reported emergence of race TTKSK/Ug99 of Pgt in Uganda reignited concerns about epidemics worldwide because ∼90% of world wheat cultivars had no resistance to the new race. Since it was initially detected in Uganda in 1998, Ug99 variants have now been identified in thirteen countries in Africa and the Middle East. Stem rust has been a major problem in the past, and concern is increasing about the risk of return to Central and East Asia. Whilst control programs in North America and Europe relied on the use of resistant cultivars in combination with eradication of barberry (Berberis spp.), the alternate host required for the stem rust pathogen to complete its full lifecycle, the focus in East Asia was principally on the use of resistant wheat cultivars. Here, we investigate potential airborne transmission pathways for stem rust outbreaks in the Middle East to reach East Asia using an integrated modelling framework combining estimates of fungal spore deposition from an atmospheric dispersion model, environmental suitability for spore germination, and crop calendar information. We consider the role of mountain ranges in restricting transmission pathways, and we incorporate a representation of a generic barberry species into the lifecycle. We find viable transmission pathways to East Asia from the Middle East to the north via Central Asia and to the south via South Asia and that an initial infection in the Middle East could persist in East Asia for up to three years due to the presence of the alternate host. Our results indicate the need for further assessment of barberry species distributions in East Asia and appropriate methods for targeted surveillance and mitigation strategies should stem rust incidence increase in the Middle East region.

Ramos-Muñoz, M., M. C. Castellanos, M. Blanco-Sánchez, B. Pías, J. A. Ramírez-Valiente, R. Benavides, A. Escudero, and S. Matesanz. 2024. Drivers of phenotypic variation and plasticity to drought in populations of a Mediterranean shrub along an environmental gradient. Environmental and Experimental Botany 228: 106011. https://doi.org/10.1016/j.envexpbot.2024.106011

Assessing the factors driving intraspecific phenotypic variation is crucial to understand the evolutionary trajectories of plant populations and predict their vulnerability to climate change. Environmental gradients often lead to phenotypic divergence in functional traits and their plasticity across populations. We studied the entire environmental range of the Mediterranean gypsum endemic shrub Helianthemum squamatum to evaluate the factors underlying quantitative population differentiation and phenotypic plasticity to drought, using a common garden with 16 populations that covered the main geographic and the entire climatic range of the species. Sampling followed a hierarchical approach to assess trait genetic variation within and among four distinct geographical regions. We found high but similar plastic responses across populations, which were consistent with adaptive plasticity to drought, including advanced phenology, more sclerophyllous leaves, higher water use efficiency and larger seeds in dry conditions. Despite these generally similar plastic responses, we found significant population differentiation in quantitative traits, part of which was structured at the regional scale. Such differentiation was not associated with environmental variation, including differences in climate and soil conditions. This suggests that non-adaptive processes might have had a role on genetic differentiation in H. squamatum, likely due to the island-like configuration of gypsum habitats and the lack of effective seed dispersal of the study species. Our results emphasize the role of phenotypic plasticity in adaptive drought response and the importance of considering both adaptive and non-adaptive processes shaping intraspecific phenotypic variation, which is crucial for predicting plant population vulnerability to climate change.

Saunders, T. C., I. Larridon, W. J. Baker, R. L. Barrett, F. Forest, E. Françoso, O. Maurin, et al. 2024. Tangled webs and spider‐flowers: Phylogenomics, biogeography, and seed morphology inform the evolutionary history of Cleomaceae. American Journal of Botany 111. https://doi.org/10.1002/ajb2.16399

Premise Cleomaceae is an important model clade for studies of evolutionary processes including genome evolution, floral form diversification, and photosynthetic pathway evolution. Diversification and divergence patterns in Cleomaceae remain tangled as research has been restricted by its worldwide distribution, limited genetic sampling and species coverage, and a lack of definitive fossil calibration points.MethodsWe used target sequence capture and the Angiosperms353 probe set to perform a phylogenetic study of Cleomaceae. We estimated divergence times and biogeographic analyses to explore the origin and diversification of the family. Seed morphology across extant taxa was documented with multifocal image‐stacking techniques and morphological characters were extracted, analyzed, and compared to fossil records.ResultsWe recovered a well‐supported and resolved phylogenetic tree of Cleomaceae generic relationships that includes 236 (~86%) species. We identified 11 principal clades and confidently placed Cleomella as sister to the rest of the family. Our analyses suggested that Cleomaceae and Brassicaceae diverged ~56 mya, and Cleomaceae began to diversify ~53 mya in the Palearctic and Africa. Multiple transatlantic disjunct distributions were identified. Seeds were imaged from 218 (~80%) species in the family and compared to all known fossil species.ConclusionsOur results represent the most comprehensive phylogenetic study of Cleomaceae to date. We identified transatlantic disjunctions and proposed explanations for these patterns, most likely either long‐distance dispersals or contractions in latitudinal distributions caused by climate change over geological timescales. We found that seed morphology varied considerably but mostly mirrored generic relationships.

Mu, J., Z. Li, Q. Lu, H. Yu, C. Hu, Y. Mu, and J. Qu. 2024. Overlooked drivers of the greenhouse effect: The nutrient-methane nexus mediated by submerged macrophytes. Water Research 266: 122316. https://doi.org/10.1016/j.watres.2024.122316

Submerged macrophytes remediation is a commonly used technique for improving water quality and restoring habitat in aquatic ecosystems. However, the drivers of success in the submerged macrophytes assembly process and their specific impacts on methane emissions are poorly understood. Thus, we conducted a mesocosm experiment to test the growth plasticity and carbon fixation of widespread submerged macrophytes (Vallisneria natans) under different nutrient conditions. A refined dynamic chamber method was utilized to concurrently collect and quantify methane emission fluxes arising from ebullition and diffusion processes. Significant correlations were found between methane flux and variations in the physiological activities of V. nantas by the fluorescence imaging system. Our results show that exceeding tolerance thresholds of ammonia in the water significantly interfered with the photosynthetic systems in submerged leaves and the radial oxygen loss in adventitious roots. The recovery process of V. natans accelerated the consumption of dissolved oxygen, leading to increase in the populations of methanogen (153.3 % increase of mcrA genes) and subsequently elevating CH4 emission fluxes (23.7 %) under high nutrient concentrations. Conversely, V. natans increased the available organic carbon under low nutrient conditions by radial oxygen loss, further increasing CH4 emission fluxes (94.7 %). Quantitative genetic and modeling analyses revealed that plant restoration processes drive ecological niche differentiation of methanogenic and methane oxidation microorganisms, affecting methane release fluxes within the restored area. The speciation process of V. natans is incapable of simultaneously meeting improved water purification and reduced methane emissions goals.