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Three new species of Chapsa in the family Graphidaceae are described from tropical Asia. Chapsa mastersonii Rivas Plata, Lumbsch & Lücking from the Philippines is characterized by large apothecia with thickly white-pruinose discs, large, muriform, non-amyloid ascospores, and the stictic acid chemosyndrome. Chapsa wijeyaratniana Weerakon, Lumbsch & Lücking from Sri Lanka has apothecia similar to the preceding species but forms an ecorticate thallus with maculiform to capitate soralia, has small, submuriform ascospores, and lacks secondary substances. Chapsa wolseleyana Weerakon, Lumbsch & Lücking forms apothecia with red to pinkish or purplish red discs and large, muriform ascospores becoming pale brown. [ABSTRACT FROM AUTHOR]

The new genus Malmographina Cáceres, Rivas Plata & Lücking is introduced for Opegrapha plicosa Meissn. (syn. Graphis malmei Redinger), with the new combination Malmographina plicosa (Meiss.) Cáceres, Rivas Plata & Lücking. The taxon is characterized by prominent, striate, orange-pigmented, non-carbonized lirellae, a more or less clear hymenium, and large, muriform, hyaline ascospores. Malmographina is most similar to Hemithecium in lirellae morphology and anatomy, but in a molecular phylogenetic analysis falls within a clade containing Phaeographis and other genera with usually inspersed hymenium and brown ascospores. Within that clade, it is thus far the only taxon that has persistently hyaline ascospores. It is otherwise similar to Pallidogramme but does not cluster within that genus. A preliminary phylogenetic analysis of the Phaeographis clade confirms monophyly of the genera Halegrapha, Pallidogramme, and Platygramme, and suggests that Phaeographis should be divided into several generic lineages and that Leiorreuma and Sarcographa perhaps be merged. [ABSTRACT FROM PUBLISHER]

Abstract: A molecular phylogeny of combined mtSSU, nuLSU, and RPB2 data revealed previously unrecognized levels of parallel evolution and phenotypic divergence in the lichen family Graphidaceae. Five clades were supported within the family: the Fissurina, Ocellularia, Graphis, Topeliopsis, and Thelotrema clades, containing 33 of the 42 currently accepted genera within the family. The results for the first time provide a fully resolved phylogeny of this family and confirm the synonymy of Graphidaceae and Thelotremataceae. Ancestral character state reconstruction using likelihood, Bayesian, and parsimony approaches indicate that lirellate ascomata evolved independently in each of the five clades. Carbonized ascomata evolved independently in at least four of the five clades. An unexpected result was the independent evolution of columella structures in the Fissurina and Ocellularia clades. Besides these more general findings, we document several cases in which evolution of several traits in parallel resulted in striking look-alikes within unrelated lineages, such as Topeliopsis muscigena and Chapsa meridensis in the Topeliopsis and Thelotrema clades, Leptotrema wightii, Myriotrema laeviusculum, and Leucodecton phaeosporum in the Ocellularia and Thelotrema clades, Ocellularia stylothecia and Melanotrema meiosporum in the Fissurina and Ocellularia clades, and Myriotrema pycnoporellum, Myriotrema clandestinum and Wirthiotrema glaucopallens in the Fissurina, Ocellularia, and Topeliopsis clades. Pagel’s test of independent character evolution suggested that at least for some of the traits involved in these cases, ecological constraints may have caused their evolution in parallel. The most intriguing find is the correlation between gall-forming thalli and vertical columns of calcium oxalate crystals, suggesting that these crystals do not function as light distributors, as previously assumed, but instead stabilize the thalli which are usually hollow beneath, similar to a dome-shaped structure. Ancestral character state reconstruction together with an approach to visualize the phenotype of putative ancestral lineages suggested the alpha-Graphidaceae to resemble some of the extant species currently classified in Myriotrema s.lat., with pore-like ascomata, and non-amyloid ascospores with lens-shaped lumina. [Copyright &y& Elsevier]

The new genus Halegrapha is introduced, with six species (five new species and one new combination) from Australia, the Philippines, Malaysia, Kenya, Mexico, and the United States: H. chimaera Rivas Plata & Lücking (type species; Philippines), H. floridana Common & Lücking (United States: Florida), H. intergrapha Hale ex Lücking (Malaysia), H. kenyana Kalb & Lücking (Kenya), H. mexicana A. B. Peña & Lücking (Mexico), and H. mucronata (Stirt.) Lücking (Australia). The genus resembles Graphis morphologically in the strongly carbonized, black lirellae and white-grey thallus strongly encrusted with calcium oxalate crystals, but has a Phaeographis-type hymenium (clear in two species) and ascospores, making it a ‘chimera’ between the two genera. Molecular data suggest the genus to be closely related to Phaeographis and allies but genetically distinct from any of the genera currently recognized, including Platygramme. [ABSTRACT FROM AUTHOR]

Molecular phylogenetic analysis presents two challenges when it is transformed into formal classifications: the taxonomic challenge (whether and how to distinguish monophyletic sister clades or how to deal with paraphyletic grades) and the nomenclatural challenge (naming clades, i.e. placing name-giving types accurately on a tree). One approach to the latter is morphology-based phylogenetic binning, which places specimens based on phenotypic features on a molecular tree and assigns uncertainty values to alternative placement options. Here, we use the example of the lichenized fungal genus L eptotrema to demonstrate how morphology-based phylogenetic binning can help to clarify taxonomic and nomenclatural issues when naming phylogenetically defined entities. L eptotrema is known for a common and widespread species, L . wightii, and phylogenetic analyses have been based exclusively on this species, including the recognition of a separate tribe, Leptotremateae. However, the genus name L eptotrema and the tribal name Leptotremateae are based on the name L . zollingeri, which was initially considered to be a synonym of L . wightii, but has recently been shown to represent a distinct species. As L . zollingeri differs considerably in phenotypic features from L . wightii, it can be questioned whether the two are at all related or whether L . zollingeri is actually closer to the genera M yriotrema and O cellularia in tribe Ocellularieae. The solution to this problem is not trivial, as it affects the correct use of the names Leptotrema and Leptotremateae. Morphology-based phylogenetic binning indeed demonstrated that L . zollingeri clusters with the M yriotrema album group in tribe Ocellularieae with high support. Hence, in contrast with current use, the name L eptotrema becomes available for the M . album group and Leptotremateae becomes a synonym of Ocellularieae. As a consequence, the new names S anguinotrema and Sanguinotremateae are introduced to accommodate L . wightii and the tribe including this species and the genus R eimnitzia. Although the studied case is specific to lichen fungi, the approach can be used in a much broader context with any kind of taxon or organism. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 179, 436-443. [ABSTRACT FROM AUTHOR]

Recently collected specimens of the crustose lichen Melaspilea demissa from south-eastern USA have been compared with those of Melaspilea spp. previously determined from North America. A review of both the historical and contemporary treatments of this species is provided. A lectotype was selected from the type collection of M. demissa in FH and is here proposed as it best matches incomplete citations in the original treatment. We also discuss the nomenclatural and taxonomic status of the name Opegrapha cymbiformis var. deformis (considered a synonym of M. gibberulosa). North American specimens of M. gibberulosa were found to be misidentifications, as were specimens attributed to M. lentiginosula, M. mesophlebia and M. octomera. We therefore recommend that these species be removed from the North American lichen checklist. We also present a key to North American Melaspilea. [ABSTRACT FROM AUTHOR]

Premise of the study: This study elucidates the phylogenetic position of a unique taxon of Graphidaceae occurring on rock in coastal desert areas, assessing its importance for our understanding of the evolution of the largest family of tropical lichenized fungi. Methods: We used maximum likelihood and Bayesian approaches to reconstruct a three-gene phylogeny of Graphidaceae and a Bayesian molecular clock approach to estimate divergence dates for major clades, as well as Bayesian ancestral ecogeography state analysis. Key results: The new genus Redonographa represents a new subfamily, Redonographoideae, sister to subfamily Graphidoideae. Redonographa is exclusively saxicolous and restricted to the American Pacific coast from California to central Chile, including Galapagos. It contains four species: Redonographa chilensis comb. nov., R. saxiseda comb. nov., R. saxorum comb. nov., an R. galapagoensis sp. nov. The genus Gymnographopsis, with a similar ecogeography but differing in excipular carbonization and chemistry, is also included in Redonographoideae, with the species G. chilena from Chile and G. latispora from So Africa. Molecular clock analysis indicates that Redonographoideae diverged from Graphidoideae about 132 million years ago (Ma) in the Early Cretaceous. Conclusions: The divergence date for subfamilies Redonographoideae and Graphidoideae coincides with the early breakup of Gondwana and ancient origin of the Atacama Desert. However, the common ancestor of Redonographoideae plus Graphidoideae was reconstructed to be tropical-epiphytic. Thus, even if Redonographoideae is subtropical-saxicolous, the hypothesis that Graphidoideae evolved from a subtropical-saxicolous ancestor is not supported. [ABSTRACT FROM AUTHOR]