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Monro, A. K.

Publications and source records attributed to Monro, A. K..

8 recordsLinked to original sources

High frequency of apomixis in subterranean islands challenges macro-climatic models of geographical parthenogenesis

The Geographical Parthenogenesis (GP) hypothesis traditionally links apomixis to high-latitude and alpine regions, driven by a combination of thermal stress, UV radiation, and pollination barriers. At the core of the GP hypothesis is Bakers Law, which asserts the evolutionary advantage of autonomous reproduction during the colonization of isolated habitats, frequently linking this advantage to macro-climatic stress. By investigating reproductive modes in subtropical subterranean karst caves, we test the core assumption that macro-climatic stress is the primary driver of apomixis. Our results suggest that barriers to pollination drive a high frequency of apomixis independently of thermal stress or UV radiation. Furthermore, we find a complete phylogenetic turnover between high-elevation, open, apomict-rich habitats and mid-elevation cave environments. Taxonomic composition in these caves is dictated by pre-adaptations to deep shade combined with a lineage-specific predisposition for autonomous reproduction. We propose that the GP hypothesis may be overly influenced by habitat sampling bias. Broader, unbiased sampling could yield a more nuanced and predictive framework to explain variations in apomixis frequency, ultimately providing deeper insights into the role of asexual reproduction in evolution

evolutionary biology↗

Setting priorities for the acquisition of primary plant occurrence data

AimEffective implementation of the Global Biodiversity Framework and Global Strategy for Plant Conservation depends on accurate species distribution data. Current vascular plant distribution data, while crucial for understanding terrestrial ecosystems, is often sparse and biased and requires significant expansion. This study developed a scalable approach to prioritize areas for plant occurrence data acquisition, adaptable to national priorities and providing a framework for botanical institutions to coordinate efforts and allocate resources. LocationGlobal. MethodsUsing a Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) analysis, we prioritized areas based on: (a) ecosystem service value; (b) floristic value threatened by climate or land-use change; and (c) uncertainty in species richness estimates, stratified by biome and region. Regional prioritization maps for Africa & Madagascar; East, South and Southeast Asia; Siberia and the Russian Far East; South America; and North & Central America were reviewed by botanical experts for validation. Scalability was assessed by comparing regional and global analyses. ResultsData-driven priority maps, divided into tree-dominated and grassland/deforested areas, largely received expert support. High similarity between global and regional maps demonstrated scalability. Main conclusionsOur approach provides a framework for supporting national implementation of the Global Biodiversity Framework. Variables and their weights can be tailored to national or local needs. The methods flexibility and adaptability extend to other taxonomic groups and objectives, such as protected area selection By prioritizing data acquisition, whether field-based or digital, this research promotes the efficient use of resources. A key advantage of this approach is its capacity to systematically translate expert opinion into explicit and quantitative criteria, which in turn facilitates clear communication with policymakers and funders.

plant biology↗

Classification of Urticaceae based on morphology and phylogenetic inference

The Urticaceae (ca. 2600 species) were first formally recognized by Jussieu in the 18th century and last comprehensively monographed by Weddell in the 19th century. Since Weddells work, family delimitation has been modified and many genera described in a fragmented manner. Over the past two decades, numerous molecular studies have supported the inclusion of Cecropiaceae within Urticaceae and identified paraphyly in several genera, notably Laportea, Urera, Boehmeria, Parietaria, Pellionia, and Pouzolzia. However, few studies have translated these molecular insights into a revised taxonomy. This study aimed to provide a robust, updated classification for Urticaceae by: a) increasing taxon and genomic locus sampling through the integration of newly generated sequence data with previously published datasets; and b) incorporating morphological data to support a revised delimitation of tribes and genera, and to establish a new linear sequence for the family. We also sought to identify remaining taxonomic challenges. Using Sanger and Angiosperms353 sequence data, we constructed a phylogenetic framework for 57 out of 59 currently accepted genera. We also assessed the phylogenetic informativeness of 57 morphological characters by mapping them onto the phylogeny. Our analyses support the delimitation of 61 monophyletic genera and an infrafamilial classification comprising seven tribes, two of which we describe as new: Myriocarpeae and Leukosykeae. We provide a revised linear sequence for the family. Our classification reinstates several names previously treated as synonyms (Fleurya, Leptocnide, Margarocarpus, Polychroa, Scepocarpus, Sceptrocnide), places several genera in synonymy (Hemistylus and Rousselia under Pouzolzia; Hesperocnide under Urtica; Gesnouinia and Soleirolia under Parietaria), and proposes the recognition of two new genera, Muimar gen. nov. and Pouzolziella gen. nov., to accommodate Boehmeria nivea and Pouzolzia australis, respectively. Mapping morphological characters onto the phylogeny indicates that while most states are homoplastic at the family level, their combination is valuable for recognizing genera. Geographic character mapping suggests a high degree of spatial conservatism at the genus rank. Our dated ultrametric tree suggests an origin for Urticaceae in Indomalaya during the mid-Cretaceous, followed by establishment in the Laurasian boreotropical flora and subsequent dispersal to the neotropics and Africa. Once classified within an evolutionary framework we believe that the Urticaceae represent a valuable study system in evolutionary biology for investigating transitions across biomes, the drivers of floral trait evolution, and intrinsic speciation mechanisms. New tribes: --Leukosykeae, Myriocarpeae New genera: --Muimar, Pouzolziella

evolutionary biology↗

Plant diversity darkspots for global collection priorities

O_LIMore than 15% of all vascular plant species may remain scientifically undescribed, and many of the >340,000 described species have no or few geographic records documenting their distribution. Identifying and understanding taxonomic and geographic knowledge shortfalls is key to prioritising future collection and conservation efforts. C_LIO_LIUsing extensive data for 343,523 vascular plant species and time-to-event analyses, we conducted multiple tests related to plant taxonomic and geographic data shortfalls, and identified 32 global diversity darkspots (regions predicted to lack most information about their species diversity and distribution). We defined priority regions for future collection according to several socio-economic and environmental scenarios. C_LIO_LIMost plant diversity darkspots are found within biodiversity hotspots, except New Guinea. We identify New Guinea, the Philippines, Borneo, Myanmar, India, Turkey, Colombia, Ecuador, and Peru, as global collection priorities under all environmental and socio-economic conditions considered. C_LIO_LIOur study provides a framework to accelerate plant species documentation for the implementation of conservation actions. As digitisation of the worlds herbaria progresses, collection and conservation priorities may soon be identifiable at finer scales. C_LI

plant biology↗

How Diverse are the Mountain karst Forests of Mexico?

Tropical forests on karstic relief (karst forest) are among the most species-rich biomes. These forests play pivotal roles as global climate regulators and for human wellbeing. Their long-term conservation could be central to global climate mitigation and biodiversity conservation. In Mexico, karst landscapes occupy 20% of the total surface and are distributed mainly in the southeast of the country, along the eastern slope, and in the Yucatan Peninsula. Within each of these areas, the following types of karst occur: coastal karst, plain karst, hill karst, and low-, medium and high-mountain karst. Mountain karst forests cover 2.07% of Mexicos surface and are covered by tropical rainforests, montane cloud forests, and tropical deciduous forests. It is probably one of the most diverse biomes in Mexico. However, the Mountain karst forest of Mexico has received little attention, and very little is known about it. Here, we evaluate the vascular plant species richness within the mountain karst forests of Mexico. We assembled the first, largest and most comprehensive datasets of Mexican, mountain karst forest species, from different public databases (CONABIO, GBIF, IBdata-UNAM), which included a critical review of all data. The families, genera and species present within the mountain karst forest of Mexico were compiled. Taxa that best characterize the forest of Mexico were identified based on their spatial correlation to this biome. Also, the conservation status of each of them was determined. We explored biodiversity patterns, identifying areas with the highest species richness, endemism centers, and areas of relatively low sampling intensity. We found that within the mountain karst forest of Mexico there are representatives of 11,771 vascular plant species (253 families and 2,254 genera), ca. 50 % of the Mexican flora. We identified 372 species endemic to these forests. According to preliminary IUCN red list criteria, 2,477 species are under some category of conservation risk, of which 456 (3.8 %) are endangered. Most of the Mexican karst forests have been extensively explored and six allopatric, species-rich areas were identified. Compared to other regions in the world, the mountain karst forest of Mexico is one of the most diverse biomes. It contains more species than some entire montane systems in Mexico such as Sierra Madre Oriental, and Sierra Madre del Sur. Also, the mountain karst forest of Mexico is most diverse than similar forests of South America and Asia, even if considering the effect of different sampling areas. The fact that mountain karst forest is covered by some of the most species-rich Mexican forests, in addition to being embedded in areas of high biotic diversity in Mexico, probably contributes to its great floristic diversity. Thus, the mountain karst forest of Mexico is an important source of diversity and shelters a large percentage of the Mexican flora.

ecology↗

Phylogeny of the species-rich Pilea Lindl. (Urticaceae) supports its revised delimitation and infrageneric classification, including the resurrection of Achudemia Blume

ABSTRACTPilea Lindl., with 933 published names is the largest genus within the Urticaceae. Pilea was last monographed in 1869 and whilst the monophyly of the genus has been proposed by previous authors, this has been based on incomplete taxon sampling and the failure to resolve the position of key taxa. We aimed to generate a robust phylogeny for Pilea and allied genera that could provide a framework for testing the monophyly of Pilea, revising its delimitation and for answering broader scientific questions about this species-rich genus. To do so, we sought to sample taxa representative of previous infrageneric classifications and with anomalous inflorescences or flower configurations and to use the resulting phylogeny to evaluate the delimitation of Pilea and to establish an infrageneric classification. In addition, we included a representative of the Polynesian genus Haroldiella which, morphologically, is very similar to Pilea. Using Sanger sequence data from two plastid and one nuclear regions we constructed a phylogeny using Bayesian Inference, Maximum Likelihood and Maximum Parsiomony approaches. We used our phylogeny to evaluate the informativness of 19 morphological traits and applied both to delimit a monophyletic genus and infrageneric sections. Our results recovered Pilea as paraphyletic with respect to Lecanthus, a consequence of the recovery of a monophyletic clade comprising sections Achudemia and Smithiella, neither of which had been adequately sampled in previous studies. We also recovered Pilea as polyphyletic with respect to Haroldiella. We identified isomery between male and female flowers, flower part number and male sepal arrangement as being phylogenetically informative traits that can be used to delimit two genera, Achudemia, including section Smithiella, recovered as sister to Lecanthus, and Pilea, including Haroldiella, recovered as sister to both. On the basis of our evaluation of both morphological traits and phylogenetic relationships we propose a new infrageneric classification for the genus comprising seven sections, five of which we describe for the first time, § Trimeris Y.G.Wei & A.K.Monro, § Lecanthoides C.J.Chen, § Angulata L.F.Fu & Y.G.Wei, § Tetrameris C.J.Chen, § Verrucosa L.F.Fu & Y.G.Wei, § Plataniflora L.F.Fu & Y.G.Wei and § Leiocarpa L.F.Fu & Y.G.Wei. We also identify a trend of decreasing merism and fruit size, and increasing species-richness as Pilea diverges. In addition, we recover strong geographical structure within our phylogeny, sufficient to propose that Pilea originated in the IndoMalaya biogeographic domain.Competing Interest StatementThe authors have declared no competing interest.View Full Text

plant biology↗

Phylogenomics of Brosimum Sw. (Moraceae) and allied genera, including a revised subgeneric system

We present a phylogenomic study of Brosimum and the allied genera Trymatococcus and Helianthostylis, with near-complete taxon sampling. Distributed from Mexico and the Greater Antilles to the Amazon, this clade contains the underutilized crop ramon (bread nut) (Brosimum alicastrum) as well as other species valued for timber or medicinal uses. Target enrichment for 333 genes produced a well-resolved phylogenetic tree and showed that Trymatoccocus and Helianthostylis are nested within Brosimum. We present a revised subgeneric classification of Brosimum based on phylogenetic and morphological considerations, including the reduction of Trymatococcus and Helianthostylis to subgenera. The monophyletic subgenera can be diagnosed based on stipule, pistillode, and cotyledon synapomorphies. Divergence date estimates suggest a Miocene origin for Brosimum, and ancestral area reconstruction indicated that all four subgenera originated and initially diversified in Amazonia before dispersing into other parts of South and Central America. ResumenPresentamos un estudio filogenomico del genero Brosimum y sus aliados, Trymatococcus y Helianthostylis, y que incluye practicamente todas las especies descritas. Su distribucion va desde Mexico y las Antillas Mayores hasta el Amazonas y comprende especies como el ramon (B. alicastrum), un cultivo infrautilizado, y otras especies empleadas como madera o en medicina. La secuenciacion masiva dirigida de 333 marcadores nucleares de copia unica permitio la reconstruccion de una filogenia bien resuelta, en la que se demuestra que Trymatococcus y Helianthostylis estan anidados en Brosimum. Presentamos, por lo tanto, una clasificacion revisada a nivel de especies, teniendo en cuenta los resultados moleculares y las caracteristicas morfologicas, y donde Trymatococcus y Helianthostylis pasan a ser subgeneros de Brosimum. Estos subgeneros monofileticos pueden ser identificados por caracteres de las estipulas y de los pistilodios.

plant biology↗

Repeated parallel losses of inflexed stamens in Moraceae: phylogenomics and generic revision of the tribe Moreae and the reinstatement of the tribe Olmedieae (Moraceae)

We present a densely-sampled phylogenomic study of the mulberry tribe (Moreae, Moraceae), an economically important clade with a global distribution, revealing multiple losses of inflexed stamens, a character traditionally used to circumscribe Moreae. Inflexed stamens facilitate ballistic pollen release and are associated with wind pollination, and the results presented here suggest that losses of this character state may have evolved repeatedly in Moraceae. Neither Moreae nor several of its major genera (Morus, Streblus, Trophis) were found to be monophyletic. A revised system for a monophyletic Moreae is presented, including the reinstatement of the genera Ampalis, Maillardia, Taxotrophis, and Paratrophis, and the recognition of the new genus Afromorus, based on Morus subgenus Afromorus. Pseudostreblus is reinstated and transferred to the Parartocarpeae, and Sloetiopsis is reinstated and transferred to the Dorstenieae. The tribe Olmediae is reinstated, replacing the Castilleae, owing to the reinstatement of the type genus Olmedia, and its exclusion from Moreae. Streblus s.s. is excluded from Moreae and transferred to the Olmediae, which is characterized primarily by involucrate inflorescences without regard to stamen position. Eight new combinations are made.

plant biology↗