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In the Flora of China account of Saxifraga mengtzeana Engl. & Irmsch., eight synonyms were attributed to it and one variant, recognized as Saxifraga epiphylla Gornall & Ohba, was split from it. This study reevaluates the taxonomic status of some of the synonyms and of the segregated species in light of new evidence presented here. Morphological and molecular evidence demonstrate that collections from northwestern Yunnan and Sichuan are genetically differentiated from those in southeastern Yunnan and neighboring Guangxi. Observations in the field and in cultivation show that the peltate petiole attachment diagnostic of S. mengtzeana var. peltifolia Engl. & Irmsch. is developmentally labile. Similar observations combined with molecular data show that viviparous phenotypes, formerly treated as S. epiphylla, although largely under genetic control, occur sporadically throughout the ranges of both northern and southern taxa. Collections from northwestern Yunnan and Sichuan are best recognized as Saxifraga geifolia Balf.f., whereas those from southeastern Yunnan and neighboring Guangxi are S. mengtzeana. Peltate‐leaved variants of the latter are given no status and are relegated to complete synonymy. Viviparous phenotypes of S. mengtzeana and S. geifolia are recognized at the rank of forma. [ABSTRACT FROM AUTHOR]

Comprising ca. 200 species, Saxifraga sect. Ciliatae is the most species‐rich section of Saxifraga s.str., whose center of diversity is in the Tibeto‐Himalayan region. The infra‐sectional classification of sect. Ciliatae is still in debate due to the high level of species richness, as well as remarkable variations of habitat, morphology, physiology and life cycles. Subdivisions of this section proposed in various taxonomic systems have not been adequately tested in previous phylogenetic studies, partly due to low taxonomic sampling density, but also to the use of few DNA markers. In order to achieve a more robust infra‐sectional classification of sect. Ciliatae, complete chloroplast genomes of 94 taxa from this section were analyzed, of which 93 were newly sequenced, assembled and annotated. The length of the 94 plastomes of sect. Ciliatae taxa range from 143,479 to 159,938 bp, encoding 75 to 79 unique protein‐coding genes (PCGs). Analyses of the 94 plastomes revealed high conservation in structural organization, gene arrangement, and gene content. Gene loss and changes of IR boundaries were detected but in extremely low frequency. The molecular phylogenetic tree from concatenated PCGs and complete chloroplast genome sequences exhibited high resolution and support values and confirms that sect. Ciliatae is monophyletic. Three well‐supported clades were revealed within the section that agree relatively well with the subsectional taxonomy of Gornall (1987), but some minor modifications should be made. Firstly, the monotypic subsection Cinerascentes should be abandoned and its constituent species, S. cinerascens, assigned to subsect. Gemmiparae. Secondly, subsections Rosulares and Serpyllifoliae should be merged and become subsect. Rosulares. Section Ciliatae thus comprises: subsect. Hirculoideae Engl. & Irmsch.; subsect. Rosulares Gornall; subsect. Gemmiparae Engl. & Irmsch.; subsect. Flagellares (C. B. Clarke) Engl. & Irmsch. and subsect. Hemisphaericae (Engl. & Irmsch.) Gornall. [ABSTRACT FROM AUTHOR]

The vascular flora of Britain and Ireland is among the most extensively studied in the world, but the current knowledge base is fragmentary, with taxonomic, ecological and genetic information scattered across different resources. Here we present the first comprehensive data repository of native and alien species optimized for fast and easy online access for ecological, evolutionary and conservation analyses. The inventory is based on the most recent reference flora of Britain and Ireland, with taxon names linked to unique Kew taxon identifiers and DNA barcode data. Our data resource for 3,227 species and 26 traits includes existing and unpublished genome sizes, chromosome numbers and life strategy and life-form assessments, along with existing data on functional traits, species distribution metrics, hybrid propensity, associated biomes, realized niche description, native status and geographic origin of alien species. This resource will facilitate both fundamental and applied research and enhance our understanding of the flora's composition and temporal changes to inform conservation efforts in the face of ongoing climate change and biodiversity loss. Measurement(s) Plant Taxonomy • Native status • Functional traits • Ellenberg indicator values • Life strategy • Associated biome • Origin of non-native species • Species distribution • Hybrid propensity • DNA barcodes • Genome size • Chromosome number Technology Type(s) digital curation • flow cytometry • Chromosome counts Sample Characteristic - Organism Tracheophyta Sample Characteristic - Environment archipelago Sample Characteristic - Location Great Britain • Ireland Machine-accessible metadata file describing the reported data: https://doi.org/10.6084/m9.figshare.16451142 [ABSTRACT FROM AUTHOR]

Most phylogeographic studies on the Qinghai-Tibetan Plateau and in adjacent regions have focused on tree or shrub species, or on herbaceous species that mainly inhabit alpine meadows or grasslands. The phylogeography of herbaceous species that inhabit woodlands and shrubberies has been largely neglected. Here we investigate the evolutionary history of a woodland- and shrubbery-inhabited herbaceous species, Rhodiola chrysanthemifolia, which grows in southern Tibet and in the mountains of the Hengduan ecoregion. The cpDNA trnL-F, rpl20- rps12 and nrDNA ITS regions of 183 individuals from 13 populations were sequenced. The ITS dataset revealed a significant phylogeographic structure across the distribution range of R. chrysanthemifolia, while the cpDNA dataset showed no significant structure. Besides, analyses of molecular variance showed that among-population variation was described as 96.27 % of the total variation for ITS marker, much higher than that for cpDNA (63.68 %). Limited seed migration among populations together with inbreeding within populations of R. chsysanthemifolia may result in the different phylogeographic and genetic patterns for ITS and cpDNA markers in this species. A high frequency and an even distribution of private cpDNA haplotypes were discovered throughout the distribution range of R. chrysanthemifolia; ITS genotypes formed three main lineages which showed a geographical distribution pattern. Furthermore, populations with above-average gene diversity were evenly spread across the current distribution range of R. chrysanthemifolia, supporting the existence of microrefugia for this species during Last Glacial Maximum, even earlier glaciations, similar to the pattern of sympatric tree and shrub species of the Juniperus tibetica complex and Hippophae tibetana. Allopatric divergence of populations in isolated microrefugia could be responsible for large number of private cpDNA haplotypes across the current distribution range of R. chrysanthemifolia. The putative factors which drove diversification between R. chrysanthemifolia and R. alsia were also discussed. [ABSTRACT FROM AUTHOR]

Nearly half of the species in the large genus Saxifraga belong to Saxifraga sect. Ciliatae, a largely Sino-Himalayan taxon. We report here that evidence from chloroplast DNA sequences (psbA-trnH, trnL-F) and from nuclear sequences (ITS) indicates that this section is monophyletic and composed of at least three main lineages, corresponding to (1) a clade made up of species from S. subsect. Gemmiparae, subsect. Cinerascentes, subsect. Flagellares and subsect. Hemisphaericae, in which the last three subsections are nested in the first; (2) a clade of species belonging to S. subsect. Rosulares (including S. subsect. Serpyllifoliaef and (3) a clade of species belonging to S. subsect. Hirculoideae. Species relationships in S. subsect. Rosulares and subsect. Hirculoideae are not well resolved. A molecular clock analysis indicates that the diversification of S. sect. Ciliatae into its three lineages dates from ca. 9.48 Ma, coinciding with orogenic events associated with one of the most important phases of uplift of the Qinghai-Tibet Plateau. Extensive diversifications within S. subsect. Rosulares and subsect. Hirculoideae have been more recent (ca. 4.51 Ma and 2.12 Ma, respectively), again correlated with Qinghai-Tibet Plateau uplift events and, in the case of S. subsect. Hirculoideae, have occurred at a rate comparable to that seen in the radiation of Hawaiian fruit flies. [ABSTRACT FROM AUTHOR]

Objective: To report the spectrum of clinical findings in patients with ocular inflammation caused by plant sap from Euphorbia species. Design: Clinical case series. Setting: Ophthalmology emergency referrals in the United Kingdom. Patients: We examined 7 patients, all of whom gave a history of recent ocular exposure to the sap of Euphorbia species. Interventions: All patients were treated with antibiotic drops or ointment (chloramphenicol). Cycloplegic and steroid drops were also used for some patients. Patients were observed until all signs and symptoms had resolved. Main Outcome Measures: Symptoms, visual acuity, and clinical signs of inflammation. All patients provided a specimen of the plant for formal identification. Results: Initial symptoms were generally burning or stinging pain with blurred vision. In most cases, visual acuity was reduced between 1 and 2 Snellen lines. In 1 patient with agerelated maculopathy, acuity dropped from 20/80 to hand motions before recovering. Clinical findings vailed from a mild epithelial keratoconjunctivitis to a severe keratitis with stromal edema, epithelial sloughing, and anterior uveitis. All signs and symptoms had resolved by 1 to 2 weeks. Conclusions: These cases illustrate the range of severity of Euphorbia sap keratouveitis. The condition seems to be self-limiting when managed supportively. People who work with Euphorbia plant species should wear eye protection. Clinicians managing keratopathy caused by Euphorbia species should be aware of the danger of sight-threatening infection and uveitis, particularly during the first few days. [ABSTRACT FROM AUTHOR]

Six hundred and forty-seven samples of Potamogeton coloratus from 60 ditches in the Gordano Valley, Somerset were analysed for variation at two polymorphic PGM isozyme loci using starch gel electrophoresis. A total of eight genotypes was detected, and a high level of partitioning of genetic variability between ditches was observed with FST=0.575. Genetic variability was shown to increase with distance from the head of the valley. The genetic subdivision of the population and pattern of increasing diversity downstream and downwind were attributed to genetic bottlenecks, associated with ditch cleaning events, and subsequent directional gene flow mediated by the prevailing wind and water currents. [ABSTRACT FROM AUTHOR]