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One new species and six new records of the crustose lichenized genus Graphis are reported from Thailand. Graphis koratensis Pitakpong, Kraichak & Lücking sp. nov. is characterized by lirelline ascocarps with whitish grey or grey-green pruina along the slit, transversely septate ascospores, and the presence of norstictic acid. Phylogenetic analyses with two loci (mtSSU and nuLSU) show the distinct position of this new species within the genus. Six new records for Thailand are reported, including G. cincta (Pers.) Aptroot, G. jejuensis K. H. Moon et al., G. nigrocarpa Adaw. & Makhija, G. renschiana (Müll. Arg.) Stizenb., G. seminuda Müll. Arg., and G. subserpentina Nyl. [ABSTRACT FROM AUTHOR]

Graphis scripta, or script lichen, is a well-known species of crustose lichenized fungi, widely distributed in the temperate region of the Northern Hemisphere. It is now considered to be a species complex, but because of the lack of secondary chemistry and paucity of measurable morphological characters, species delimitation within the complex has been challenging and is thus far based on apothecium and ascospore morphology. In this study, we employed molecular as well as morphological data to assess phylogenetic structure and delimitation of lineages within the G. scripta complex. We generated sequences for four genetic markers (mtSSU, nuLSU, RPB2, and EF-1) and performed phylogenetic analyses. The resulting trees were used to determine the number of distinct lineages by applying a general mixed Yule-coalescent (GMYC) model and species tree estimation through maximum likelihood (STEM). Our analyses suggest between six and seven putative species within the G. scripta complex. However, these did not correspond to the taxa that were recently distinguished based on apothecium morphology and could not be circumscribed with the morphological characters that were traditionally used in the classification of the complex. Any formal taxonomic treatment will require additional sampling and evaluation of additional traits that potentially can characterize these clades. [ABSTRACT FROM AUTHOR]

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 Graphis s.l. (Ascomycota: Ostropales: Graphidaceae), which was recently shown to represent two separate, distantly related lineages, Graphis s.str. and Allographa. Of 313 species of Graphis and Allographa included 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 Graphis or Allographa with strong support (90%-100%). Two species, G. saxiseda and 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 RAxM L v.7.2.6 Windows executable and the RAxM L v.7.2.8 open-source code. [ABSTRACT FROM AUTHOR]