Applying molecular methods to fungi establishing lichenized associations with green algae or cyanobacteria has repeatedly revealed the existence of numerous phylogenetic taxa overlooked by classical taxonomic approaches. Here, we report taxonomical conclusions based on multiple species delimitation and validation analyses performed on an eight-locus dataset that includes world-wide representatives of the dolichorhizoid and scabrosoid clades in section Polydactylon of the genus Peltigera . Following the recommendations resulting from a consensus species delimitation approach and additional species validation analysis (BPP) performed in this study, we present a total of 25 species in the dolichorhizoid clade and nine in the scabrosoid clade, including respectively 18 and six species that are new to science and formally described. Additionally, one combination and three varieties (including two new to science) are proposed in the dolichorhizoid clade. The following 24 new species are described: P. appalachiensis , P. asiatica , P. borealis , P. borinquensis , P. chabanenkoae , P. clathrata , P. elixii , P. esslingeri , P. flabellae , P. gallowayi , P. hawaiiensis , P. holtanhartwigii , P. itatiaiae , P. hokkaidoensis , P. kukwae , P. massonii , P. mikado , P. nigriventris , P. orientalis , P. rangiferina , P. sipmanii , P. stanleyensis , P. vitikainenii and P. willdenowii ; the following new varieties are introduced: P. kukwae var. phyllidiata and P. truculenta var. austroscabrosa ; and the following new combination is introduced: P. hymenina var. dissecta . Each species from the dolichorhizoid and scabrosoid clades is morphologically and chemically described, illustrated, and characterised with ITS sequences. Identification keys are provided for the main biogeographic regions where species from the two clades occur. Morphological and chemical characters that are commonly used for species identification in the genus Peltigera cannot be applied to unambiguously recognise most molecularly circumscribed species, due to high variation of thalli formed by individuals within a fungal species, including the presence of distinct morphs in some cases, or low interspecific variation in others. The four commonly recognised morphospecies: P. dolichorhiza , P. neopolydactyla , P. pulverulenta and P. scabrosa in the dolichorhizoid and scabrosoid clades represent species complexes spread across multiple and often phylogenetically distantly related lineages. Geographic origin of specimens is often helpful for species recognition; however, ITS sequences are frequently required for a reliable identification.
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Phylogenetic analyses and species delimitation of Aconurella Ribaut (Hemiptera: Cicadellidae: Deltocephalinae: Chiasmini) in China based on molecular data
The grassland leafhopper genus Aconurella is widespread in the Old World. Species of this genus are difficult to identify by traditional morphological characters but the morphology-based species classification in this genus has not previously been tested using molecular data. This study analysed DNA sequence data from two mitochondrial genes (COI, 16S) and one nuclear gene (ITS2) to infer the phylogenetic relationships and status of five previously recognized Aconurella species and compare the performance of different molecular species-delimitation methods using single and multiple loci. The analysis divided the included haplotypes into five well-supported subclades, most corresponding to existing morphology-based species concepts. However, different molecular species delimitation methods (jMOTU, ABGD, bPTP, GMYC and BPP) yielded somewhat different results, suggesting the presence of between 4 and 8 species, sometimes lumping the haplotypes of Aconurella diplachnis and Aconurella sibirica into a single species or recognizing multiple putative species within Aconurella prolixa. Considering the different results yielded by various methods employing single loci, the BPP method, which combines data from multiple loci, may be more reliable for delimiting species of Aconurella. Our results suggest that the morphological characters previously used to identify these species are reliable and adequately reflect boundaries between genetically distinct taxa.
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- Award ID(s):
- 1639601
- NSF-PAR ID:
- 10383093
- Date Published:
- Journal Name:
- Zootaxa
- Volume:
- 5205
- Issue:
- 3
- ISSN:
- 1175-5326
- Page Range / eLocation ID:
- 281 to 296
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.11646/zootaxa.5205.3.6
