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Peltigera globulata Miadl. & Magain, a new species in the P. ponojensis/monticola species complex of section Peltigera , is formally described. This clade was previously given the interim designation Peltigera sp. 17. It is found in sun-exposed and xeric habitats at high altitudes in Peru and Ecuador. Peltigera globulata can be easily recognized by its irregularly globulated margins covered mostly by thick, white pruina, somewhat resembling the sorediate thallus margins of P. soredians , another South American species from section Peltigera. The hypervariable region of ITS1 (ITS1-HR), which is in general highly variable among species of section Peltigera , does not have diagnostic value for species identification within the P. ponojensis/monticola complex. Nevertheless, no significant level of gene flow was detected among eight lineages representing a clade of putative species (including P. globulata) within this complex. ITS sequences from the holotype specimens of P. monticola Vitik. (collected in 1979) and P. soredians Vitik. (collected in 1981) and lectotype specimens of P. antarctica C. W. Dodge (collected in 1941) and P. aubertii C. W. Dodge (collected in 1952) were successfully obtained through Sanger and Illumina metagenomic sequencing. BLAST results of these sequences revealed that the type specimen of P. monticola falls within the P. monticola/ponojensis 7 clade, which represents P. monticola s. str., and confirmed that the type specimen of P. aubertii falls within a clade identified previously as P. aubertii based on morphology. The ITS sequence from the type specimen of P. soredians , which superficially resembles P. globulata , confirms its placement in the P. rufescens clade. Finally, we discovered that the name P. antarctica was erroneously applied to a lineage in the P. ponojensis/monticola clade. The ITS sequence from the type specimen of P. antarctica represents a lineage within the P. rufescens clade, which is sister to the P. ponojensis/monticola clade. [ABSTRACT FROM AUTHOR]

A checklist of Lichen-forming, Lichenicolous and Allied Fungi of Ecuador is presented with a total of 2599 species, of which 39 are reported for the first time from the country. The names of three species, Hypotrachyna montufariensis , H. subpartita and Sticta hypoglabra , previously not validly published, are validated. Pertusaria oahuensis , originally introduced by Magnusson as ' ad interim ', is validated as Lepra oahuensis. The form Leucodermia leucomelos f. albociliata is validated. Two new combinations, Fissurina tectigera and F. timida , are made, and Physcia mobergii is introduced as a replacement name for the illegitimate P. lobulata Moberg non (Flörke) Arnold. In an initial step, the checklist was compiled by reviewing literature records of Ecuadorian lichen biota spanning from the late 19th century to the present day. Subsequently, records were added based on vouchers from 56 collections participating in the Consortium of Lichen Herbaria , a Symbiota-based biodiversity platform with particular focus on, but not exclusive to, North and South America. Symbiota provides sophisticated tools to manage biodiversity data, such as occurrence records, a taxonomic thesaurus, and checklists. The thesaurus keeps track of frequently changing names, distinguishing taxa currently accepted from ones considered synonyms. The software also provides tools to create and manage checklists, with an emphasis on selecting vouchers based on occurrence records that can be verified for identification accuracy. Advantages and limitations of creating checklists in Symbiota versus traditional ways of compiling these lists are discussed. Traditional checklists are well suited to document current knowledge as a 'snapshot in time'. They are important baselines, frequently used by ecologists and conservation scientists as an established naming convention for citing species reported from a country. Compiling these lists, however, requires an immense effort, only to inadequately address the dynamic nature of scientific discovery. Traditional checklists are thus quickly out of date, particularly in groups with rapidly changing taxonomy, such as lichenized fungi. Especially in megadiverse countries, where new species and new occurrences continue to be discovered, traditional checklists are not easily updated; these lists necessarily fall short of efficiently managing immense data sets, and they rely primarily on secondary evidence (i.e. literature records rather than specimens). Ideally, best practices make use of dynamic database platforms such as Symbiota to assess occurrence records based both on literature citations and voucher specimens. Using modern data management tools comes with a learning curve. Systems like Symbiota are not necessarily intuitive and their functionality can still be improved, especially when handling literature records. However, online biodiversity data platforms have much potential in more efficiently managing and assessing large biodiversity data sets, particularly when investigating the lichen biota of megadiverse countries such as Ecuador. [ABSTRACT FROM AUTHOR]

Prokaryotic genomes are often considered to be mosaics of genes that do not necessarily share the same evolutionary history due to widespread horizontal gene transfers (HGTs). Consequently, representing evolutionary relationships of prokaryotes as bifurcating trees has long been controversial. However, studies reporting conflicts among gene trees derived from phylogenomic data sets have shown that these conflicts can be the result of artifacts or evolutionary processes other than HGT, such as incomplete lineage sorting, low phylogenetic signal, and systematic errors due to substitution model misspecification. Here, we present the results of an extensive exploration of phylogenetic conflicts in the cyanobacterial order Nostocales, for which previous studies have inferred strongly supported conflicting relationships when using different concatenated phylogenomic data sets. We found that most of these conflicts are concentrated in deep clusters of short internodes of the Nostocales phylogeny, where the great majority of individual genes have low resolving power. We then inferred phylogenetic networks to detect HGT events while also accounting for incomplete lineage sorting. Our results indicate that most conflicts among gene trees are likely due to incomplete lineage sorting linked to an ancient rapid radiation, rather than to HGTs. Moreover, the short internodes of this radiation fit the expectations of the anomaly zone, i.e. a region of the tree parameter space where a species tree is discordant with its most likely gene tree. We demonstrated that concatenation of different sets of loci can recover up to 17 distinct and well-supported relationships within the putative anomaly zone of Nostocales, corresponding to the observed conflicts among well-supported trees based on concatenated data sets from previous studies. Our findings highlight the important role of rapid radiations as a potential cause of strongly conflicting phylogenetic relationships when using phylogenomic data sets of bacteria. We propose that polytomies may be the most appropriate phylogenetic representation of these rapid radiations that are part of anomaly zones, especially when all possible genomic markers have been considered to infer these phylogenies. [Anomaly zone; bacteria; horizontal gene transfer; incomplete lineage sorting; Nostocales; phylogenomic conflict; rapid radiation; Rhizonema.] [ABSTRACT FROM AUTHOR]

The genus Dendriscosticta (Ascomycota: Peltigerales) encompasses several distinctive lichen‐forming fungal species restricted to the Northern Hemisphere. Most are flagship species of old‐growth forests with good air quality. A global phylogeny of the genus based on multilocus sequence data (ITS, RPB1, EF‐1α, MCM7), model‐based phylogenetic methods, and morphological and chemical assessments, reveals a high level of cryptic speciation often associated with restricted geographical distribution and/or chemical characters. Using sequence‐based species delimitation approaches, we circumscribe two main clades referred to as the D. wrightii clade, with five unequivocal species, including D. gelida sp. nov., and the D. praetextata clade, with eight putative species, including D. phyllidiata sp. nov. The absence of recently collected material of D. hookeri comb. nov. from the type locality unfortunately prevents assignment of this epithet to one of the five supported lineages sharing this morphotype. Three new combinations are proposed: D. hookeri, D. insinuans comb. nov. and D. yatabeana comb. nov. Epitypes are designated for D. wrightii and D. yatabeana. Species diversity within the genus increased from four to nine. Our morphological assessment confirmed that Sticta and Dendriscosticta can be readily distinguished by the presence of excipular algae whereas the structure of the lower surface pores is not a reliable diagnostic feature. [ABSTRACT FROM AUTHOR]