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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. wrightiiclade, with five unequivocal species, including D. gelidasp. nov., and the D. praetextataclade, with eight putative species, including D. phyllidiatasp. nov. The absence of recently collected material of D. hookericomb. 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. insinuanscomb. nov. and D. yatabeanacomb. nov. Epitypes are designated for D. wrightiiand D. yatabeana. Species diversity within the genus increased from four to nine. Our morphological assessment confirmed that Stictaand Dendriscostictacan be readily distinguished by the presence of excipular algae whereas the structure of the lower surface pores is not a reliable diagnostic feature.

Traditional taxonomic studies provide only a limited understanding of species richness within a group. Their usefulness for assessing species diversity could also be limited as many lack sufficient sampling and/or fail to integrate different data types for assessing species boundaries. To explore the challenges and limitations of estimating species richness in lichens, we employed an integrative taxonomic approach to elucidate diversification patterns of the genus Sticta(Peltigeraceae) in Puerto Rico. Specimens were collected throughout the island, and a six‐locus dataset was generated to infer phylogenetic relationships among Puerto Rican Stictaand their continental counterparts. Phylogenetic analysis was combined with species delimitation methods and analysis of morpho‐anatomical characters to assess diversity patterns and clarify species‐level taxonomy. We found that Stictais represented by 16 species in Puerto Rico and that at least 11 (69%) of them are potentially endemic to the island. We describe eight of these in this work: S. borinquensissp. nov., S. corymbosasp. nov., S. densiphyllidiatasp. nov., S. guilartensissp. nov., S. harrisiisp. nov., S. parvilobatasp. nov., S. ripariasp. nov., and S. tainorumsp. nov. These species do not cluster in a monophyletic assemblage but are scattered over the broader Stictaphylogeny, indicating at least eight separate dispersal events. Putative endemic species were found to have close allies occurring in South America. Careful re‐examination of material revealed phenotypical characters that separate most species, suggesting low levels of cryptic diversity. We highlight that integrating molecular methods and other sources of information in species discovery along with comprehensive sampling efforts can greatly enhance our knowledge about diversity patterns in poorly studied groups and regions. Furthermore, species and ecosystems in the Caribbean are being threatened by substantial human‐driven changes (e.g., deforestation, climate change). Consequences of these impacts include reduction in already restricted habitats and potential extinction. We argue that studies analyzing species diversity within a phylogenetic framework could better inform conservation efforts aimed at addressing these challenges.

Lineages with broad, intercontinental distributions can provide insight into factors that influence diversity across both temporal and geographic scales. Lichens are well known for distinct biogeographic distribution patterns, including a high number of lineages with intercontinental distributions. The lichen-forming fungal genus Oropogon, from one of the largest families of lichen-forming ascomycetes, Parmeliaceae, occurs in both Asia and the Neotropics. How this genus obtained this disjunct distribution is not currently known. To better understand factors shaping diversity in Oropogon, we (i) estimated the timing of diversification of major clades within this genus; (ii) inferred the historical biogeography of Oropogon; and (iii) identified factors that potentially affected the distribution and evolution of this genus. Our results suggest that the genus originally radiated during the early Miocene, with subsequent diversification events occurring during the middle Miocene. Ancestral area reconstructions for Oropogonsuggest that the genus was either widespread with subsequent separate diversification in Asia and America or originated in the New World (America), with subsequent migration to Asia. We hypothesize that the Mi-1 glaciation impacted diversification of Oropogonspecies in Asia, and that the rise of major mountain ranges, such as the Himalayas, helped promote diversification in Oropogonin the Old World.

In this paper, an extended molecular phylogeny was generated for the Ocellulariaclade, which includes about half of the species that were previously separated in the family Thelotremataceae. Three genes (mtSSU, nuLSU, RPB2), from a total of 270 OTUs with 136 ingroup species, were sequenced to evaluate whether the core genera, Ocellulariaand Myriotrema, form monophyletic clades or split into several lineages. Further, we tested the usefulness of phenotypic characters for circumscrib ing monophyletic groups. Besides a maximum likelihood analysis, we incorporated the novel method of morphology-based 'phylogenetic binning', which allowed us to weight the morphological characters in those taxa with molecular data available and then predict the phylogenetic classification for over 200 additional species for which no molecular data are currently available. Our results showed that the large genera Myriotrema, Ocellularia, and Stegobolusare polyphyletic. For some of the previously unrecognized lineages, older generic names are available (Rhabdodiscus, Ocellis, Stigmagora, Antrocarpum, Macropyrenium). Some previously separated genera, such as Ampliotremaand Gyrotrema, were found to be nested within a large clade currently recognized as Ocellularias.l. For this clade, no meaningful generic subdivision could be established based on the available data, and we proposed to recognize distinct subclades at the subgenus level. One new genus, Compositrema, was also discovered, and a second new genus, Glaucotrema, is established for the Myriotrema glaucophaenumgroup. Further, the genus Rhabdodiscusis reinstated formally. We found a high level of homoplasy (parallel evolution) of phenotype characters previously used for classification purposes, such as excipular carbonization, columella morphology, and ascospore size, septation, and pigmentation. Secondary chemistry, on the other hand, was remarkably uniform in most clades. Some clades also exhibit a high level of disparity of ascoma morphology. Thus, the very distinctive Gyrotrema-type apothecia occur in a clade nested within and genetically very similar to Ocellularias.str.

Despite their potential shortcomings for phylogenetic inference, sometimes only morphological data are available for systematic classification. Computational methods are used to determine morphological site patterns congruent with the molecular tree in order to improve the accuracy of the classification of taxa for which only morphological data exist. Here, we used molecular site weight calibration as implemented in RAxML to weight morphological characters based on their distribution on a maximum likelihood tree inferred from molecular data. We subsequently conducted morphology-based 'phylogenetic binning' (= assignment of morphologically defined taxa that lack molecular data to branches of the molecular reference tree) based on the morphology of the taxa included in the tree. We applied this methodology to the lichen genus Graphiss.l. (Ascomycota: Ostropales: Graphidaceae), which was recently shown to represent two separate, distantly related lineages, Graphiss.str. and Allographa. Of 313 species of Graphisand Allographaincluded in the study, 16 were represented by molecular sequence data and morphology, and 297 by morphology only. Using maximum likelihood and maximum parsimony site weight calibration and morphology-based phylogenetic binning, 281–290 of the 297 species represented by morphological data only could be assigned to either Graphisor Allographawith strong support (90%–100%). Two species, G. saxisedaand G. evirescens, were found to represent species of the unrelated genus Carbacanthographis. Our results showed that assignment of taxa to clades based on morphological data only substantially improved with molecular site weight calibration. Both molecular site weight calibration and branch assignment to the molecular reference tree are implemented in the RAxML v.7.2.6 Windows executable and the RAxML v.7.2.8 open-source code.

Molecular phylogenetic analysis of the mitochondrial small subunit and nuclear large subunit ribosomal DNA revealed that the lichen genus Graphissensu Staiger represents two separate lineages. Graphiss.str. comprises the species of the G. scriptaand G. subserpentinagroups (‘Eugraphis’), as well as the G. striatulagroup sensu Lücking. For the segregate genus, the name AllographaChevall. is available, and this genus includes the G. acharii, G. dussii, G. marginata, G. nuda, and G. symplectagroups. The separation of both lineages is supported by principal component analysis species ordination based on phenotype characters, although the G. dussiiand G. subserpentinagroups appear phenotypically intermediate. Species formerly placed in Hemitheciumsubg. Hemitheciumsensu Staiger were shown to belong to at least four lineages, one nested within Graphis(H. implicatum), one within Allographa(H. chlorocarpum), one sister to Allographa(H. rufopallidum), and one nested within the Phaeographisclade (H. plicosum). Allographa is genetically close to the bulk of lirellate Graphidaceae (Diorygma, Glyphis, Pallidogramme, Phaeographis, Platygramme, Platythecium, Sarcographa, Thalloloma, Thecaria), whereas Graphiss.str. exhibits unique genetic apomorphies and takes a more isolated position.

Lücking, R. & Kalb, K.: Echinoplaca vezdana:a new lichenised fungus. ‐ Taxon 50: 837–840. 2001. ‐ ISSN 0040‐0262. The lichenised fungus Echinoplaca vezdanafrom the Philippines is described and illustrated. It has a comparatively large thallus, large apothecia, and 2–4 muriform ascospores per ascus. The new taxon is closely related to E. diffluens, which differs in having transversely septate ascospores. The two species form another pair of morphologically similar taxa differing in ascospore types of which five were previously known. Echinoplaca vezdanais dedicated to Antonín Vňzda, one of the outstanding lichen taxonomists of the 20thcentury, on the occasion of his recent 80thbirthday.