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India harbours 12 species of Pallidogramme, including P. chapadana (Redinger) Staiger, Kalb & Lücking, which is being reported as new record for the country. In addition, two species, viz. P. bengalensis B.O. Sharma & Khadilkar and P. chrysenteron (Mont.) Staiger, Kalb & Lücking have their known distribution range within India expanded. A detailed description and illustrations are provided for the new country record and comments are made on expanded distribution ranges. A world key to all known species of Pallidogramme is provided. [ABSTRACT FROM AUTHOR]

The order Trentepohliales comprises a diverse and widespread group of green algae in temperate and tropical regions. The free-living representatives of this order have been investigated in more detail, whereas less is known about the trentepohlialean photobionts of lichens. Selected lichen species of the family Graphidaceae ( Graphis propinqua, Graphis scripta, Graphis submarginata) from different climatic regions were chosen for the isolation of trentepohlialean photobionts. Three different nutrient media (modified Bold's Basal medium, modified Woods Hole MBL medium, optimal Haematococcus medium) were tested for the cultivation of these algae. The differences of the growth reactions of the isolated photobionts in culture were studied examining morphological characteristics, reproductive strategies and variations in carotenoid accumulation. The phylogenetic positions of the photobionts were investigated using sequences of the 18S rRNA gene, ITS region, and rbcL gene. Three photobiont strains were identified as Printzina lagenifera and one as Trentepohlia sp. according to the phylogenetic data and the morphological observations under culture conditions. [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]

The fungal order Ostropales is unique in Ascomycota for including both lichen-forming and non-lichenized species and species with optional nutritional strategies depending on substrate. To address the phylogenetic relationships within the order, we assembled a dataset of 78 ostropalean species, including all major clades and 23 taxa that are only optionally lichenized or non-licl1ienized. The analyses are based on sequences of the mtSSU and nuLSU rDNA and the protein-coding gene RPB2. A close relationship of Graphidaceae and Gomphillaceae is suggested with the latter possibly nested within Graphidaceac. Odontotremataceae is composed of two distantly related groups. Coenogoniaceae and Porinaceae are sister taxa, and their relation to Gyalectaceae is unresolved. Gyalecta is paraphyletic with Belonia and Pachyphiale nested within. A polyphyletic Belonia indicates that perithecloid ascomata evolved more than once in Gyalectaceae. The new family Sagiolechiaceae is proposed to aLcommodate Rhexophiale and Sagiolechia and Solorinellaceae is reinstated distinct from Gomphillaceae. Belonia and Pachyphiale are reduced to synonymy with Gyalecta. The distribution of phenotypical character states is discussed with selected character states mapped onto a phylogenetic tree. A special focus is given on lifestyles. Our phylogeny suggests that there is more plasticity in the evolution of life-styles in these fungi than was previously assumed. [ABSTRACT FROM AUTHOR]

Aim To analyse the historical biogeography of the lichen genus Chroodiscus using a phenotype-based phylogeny in the context of continental drift and evolution of tropical rain forest vegetation. Location All tropical regions (Central and South America, Africa, India, Southeast Asia, north-east Australia). Methods We performed a phenotype-based phylogenetic analysis and ancestral character state reconstruction of 14 species of the lichen genus Chroodiscus, usingpaup* andmesquite; dispersal–vicariance analysis (DIVA) and dispersal–extinction–cladogenesis (DEC) modelling to trace the geographical origin of individual clades; and ordination and clustering by means ofpc-ord, based on a novel similarity index, to visualize the biogeographical relationships of floristic regions in which Chroodiscus occurs. Results The 14 species of Chroodiscus show distinctive distribution patterns, with one pantropical and one amphi-Pacific taxon and 12 species each restricted to a single continent. The genus comprises four clades. DIVA and DEC modelling suggest a South American origin of Chroodiscus in the mid to late Cretaceous (120–100 Ma), with subsequent expansion through a South American–African–Indian–Southeast Asian–Australian dispersal route and late diversification of the argillaceus clade in Southeast Asia. Based on the abundance of extant taxa, the probability of speciation events in Chroodiscus is shown to be extremely low. Slow dispersal of foliicolous rain forest understorey lichens is consistent with estimated phylogenetic ages of individual species and with average lengths of biological species intervals in fungi (10–20 Myr). Main conclusions The present-day distribution of Chroodiscus can be explained by vicariance and mid-distance dispersal through the interconnection or proximity of continental shelves, without the need for recent, trans-oceanic long-distance dispersal. Phylogenetic reconstruction and age estimation for Chroodiscus are consistent with the ‘biotic ferry’ hypothesis: a South American origin and subsequent eastward expansion through Africa towards Southeast Asia and north-eastern Australia via the Indian subcontinent. The present-day pantropical distributions of many clades and species of foliicolous lichens might thus be explained by eastward expansion through continental drift, along with the evolution of modern rain forests starting 120 Ma, rather than by the existence of a hypothetical continuous area of pre-modern rain forest spanning South America, Africa and Southeast Asia during the mid and late Cretaceous. [ABSTRACT FROM AUTHOR]

Family concepts in lichen-forming fungi are poorly understood and were traditionally based on easily observable characters. An example is the family Thelotremataceae, a species-rich group of crustose, predominantly tropical lichens with over 1,000 described species. Its distinction from Graphidaceae is largely based on ascoma shape (round vs. lirelliform). Previous studies already indicated that the distinction of these families is doubtful. However, these studies only included a few taxa of Thelotremataceae. Hence we obtained 96 new partial sequences of nuclear and mitochondrial ribosomal DNA, mostly of Thelotremataceae. We performed maximum parsimony and Bayesian phylogenetic analyses of a combined dataset of 105 samples, representing 97 species. Our results indicate that Graphidaceae and Thelotremataceae cannot be separated, but form several lineages within one strongly supported monophyletic lineage. Monophyly of Graphidaceae and Thelotremataceae each in their present circumscription was rejected significantly using two independent alternative topology tests. Consequently, Thelotremataceae is reduced to synonymy with Graphidaceae. Further, numerous genera in Graphidaceae and Thelotremataceae were found to be para- or polyphyletic, including all genera currently placed in Thelotremataceae, with the sole exception of Diploschistes. In Graphidaceae, Graphis and Sarcographa are polyphyletic as currently circumscribed. However, since the topology within Graphidaceae s.l. largely lacks support and given the large number of species not yet studied, a thorough evaluation of the generic concept requires a larger dataset, including additional genes and taxa. [ABSTRACT FROM AUTHOR]