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  1. We present the whole genome sequences of Dryas alaskensis, D. ajanensis, and D. integrifolia from plants collected from interior Alaska. We performed deep Illumina sequencing of a single leaf of each voucher. The sequence reads were then de novo assembled and conserved regions across all preassemblies were used to join contigs in a finishing step. The raw and assembled data is publicly available via Genbank. 
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  2. We present the whole genome sequences of 56 wild Erythroxylum species from Africa, China, and the American tropics. Deep Illumina sequencing was performed on a single leaf of each voucher. We de novo assembled sequence reads and then identified and used conserved regions across all preassemblies join contigs in a finishing step. The raw and assembled data is publicly available via Genbank. 
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  3. Erythroxylum macrophyllum is a morphologically variable and widely distributed species complex in Central and South America with several sub-specific taxa and numerous species included in its synonymy. A single variety grows in the Colombo-Venezuelan savanna region which can be distinguished from the rest of the E. macrophyllum complex by the size of leaves, cataphyll and stipule characteristics, and shape of calyx lobes. A molecular phylogeny reconstructed from 519 nuclear genes also reveals that the savanna variety is more closely related to E. acuminatum and E. pauciflorum than E. macrophyllum. This phylogenomic evidence also suggests Erythroxylum sect. Macrocalyx, to which E. macrophyllum belongs, is a polyphyletic taxonomic section. We thus propose elevating this variety to specific status, as Erythroxylum savannarum. We provide an updated taxonomic description, information about its habitat and distribution, and justify its informal IUCN cat- egorization of Near Threatened (NT) 
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  4. We report the rediscovery of the Critically Endangered cloud forest herb Gasteranthus extinctus , not seen since 1985. In 2019 and 2021, G. extinctus was recorded at five sites in the western foothills of the Ecuadorian Andes, 4–25 km from the type locality at the celebrated Centinela ridge. We describe the species’ distribution, abundance, habitat and conservation status and offer recommendations for further research and conservation efforts focused on G. extinctus and the small, disjunct forest remnants it occupies. 
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  6. Summary

    Leaf reflectance spectroscopy is emerging as an effective tool for assessing plant diversity and function. However, the ability of leaf spectra to detect fine‐scale plant evolutionary diversity in complicated biological scenarios is not well understood.

    We test if reflectance spectra (400–2400 nm) can distinguish species and detect fine‐scale population structure and phylogenetic divergence – estimated from genomic data – in two co‐occurring, hybridizing, ecotypically differentiated species ofDryas. We also analyze the correlation among taxonomically diagnostic leaf traits to understand the challenges hybrids pose to classification models based on leaf spectra.

    Classification models based on leaf spectra identified two species ofDryaswith 99.7% overall accuracy and genetic populations with 98.9% overall accuracy. All regions of the spectrum carried significant phylogenetic signal. Hybrids were classified with an average overall accuracy of 80%, and our morphological analysis revealed weak trait correlations within hybrids compared to parent species.

    Reflectance spectra captured genetic variation and accurately distinguished fine‐scale population structure and hybrids of morphologically similar, closely related species growing in their home environment. Our findings suggest that fine‐scale evolutionary diversity is captured by reflectance spectra and should be considered as spectrally‐based biodiversity assessments become more prevalent.

     
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  7. Abstract

    This work shows the ability of a readily‐available oxidizer to achieve the selective oxidation of 3,5‐diamino‐1,2,4‐triazole (DAT) to 3‐amino‐5‐nitro‐1,2,4‐triazole (ANTA) in high yields. This strategy reduces the synthesis of this important energetic material and synthon down to a single step. Analysis was conducted on the product and confirmed that the product was indeed ANTA. The yield, safety, and economics of this process are all superior to the current state‐of‐the‐art two‐step multi‐pot procedure.

     
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  8. Premise of the Study

    This investigation establishes the firstDNA‐sequence‐based phylogenetic hypothesis of species relationships in the coca family (Erythroxylaceae) and presents its implications for the intrageneric taxonomy and neotropical biogeography ofErythroxylum. We also identify the closest wild relatives and evolutionary relationships of the cultivated coca taxa.

    Methods

    We focused our phylogenomic inference on the largest taxonomic section in the genusErythroxylum(ArcherythroxylumO.E.Schulz) using concatenation and gene tree reconciliation methods from hybridization‐based target capture of 427 genes.

    Key Results

    We show that neotropicalErythroxylumare monophyletic within the paleotropical lineages, yetArcherythroxylumand all of the other taxonomic sections from which we sampled multiple species lack monophyly. We mapped phytogeographic states onto the tree and found some concordance between these regions and clades. The wild speciesE. gracilipesandE. cataractarumare most closely related to the cultivatedE. cocaandE. novogranatense, but relationships within this “coca” clade remain equivocal.

    Conclusions

    Our results point to the difficulty of morphology‐based intrageneric classification in this clade and highlight the importance of integrative taxonomy in future systematic revisions. We can confidently identifyE. gracilipesandE. cataractarumas the closest wild relatives of the coca taxa, but understanding the domestication history of this crop will require more thorough phylogeographic analysis.

     
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