Felix Grewe | Field Museum (original) (raw)
Papers by Felix Grewe
Genome Biology and Evolution, 2011
Using an independent fosmid cloning approach and comprehensive transcriptome analysis to compleme... more Using an independent fosmid cloning approach and comprehensive transcriptome analysis to complement data from the Selaginella moellendorffii genome project, we determined the complete mitochondrial genome structure of this spikemoss. Numerous recombination events mediated mainly via long sequence repeats extending up to 7kbp result in a complex mtDNA network structure. Peculiar features associated with the repeat sequences are more than 80 different microsatellite sites (predominantly trinucleotide motifs). The S. moellendorffii mtDNA encodes a plant-typical core set of a twin-arginine translocase (tatC), 17 respiratory chain subunits, and 2 rRNAs but lacks atp4 and any tRNA genes. As a further novelty among plant chondromes, the nad4L gene is encoded within an intron of the nad1 gene. A total of 37 introns occupying the 20 mitochondrial genes (four of which are disrupted into trans-splicing arrangements including two novel instances of transsplicing introns) make the S. moellendorffii chondrome the intron-richest and gene-poorest plant mtDNA known. Our parallel transcriptome analyses demonstrates functional splicing of all 37 introns and reveals a new record amount of plant organelle RNA editing with a total of 2,139 sites in mRNAs and 13 sites in the two rRNAs, all of which are exclusively of the C-to-U type.
Fungal Diversity
Rapid radiations in Fungi are only beginning to be studied with phylogenomic data. The evolutiona... more Rapid radiations in Fungi are only beginning to be studied with phylogenomic data. The evolutionary history of the lichenized fungal order Peltigerales has not been well resolved, particularly for the Collematineae. Here, we used concatenation and coalescent-based species tree methods to reconstruct the phylogeny of the Peltigerales based on sequences of 125 nuclear single-copy exon sequences among 60 samples, representing 58 species. Despite uneven, lineage-specific missing data and significant topological incongruence of individual exon trees, the resulting phylogenies were concordant and successfully resolved the phylogenetic relationships of the Peltigerales. Relationships in the Collematineae were defined by short branches and lower nodal support than in other parts of the tree, due in part to conflicting signal in exon trees, suggesting rapid diversification events in the early evolution of the suborder. Using tree distance measures, we were able to identify a minimum subset of exons that could reconstruct phylogenetic relationships in Peltigerales with higher support than the 125-exon dataset. Comparisons between the minimum and complete datasets in species tree inferences, bipartition analyses, and divergence time estimations displayed similar results, although the minimum dataset was characterized by higher levels of error in estimations of divergence times. Contrasting our inferences from the complete and minimum datasets to those derived from few nuclear and mitochondrial loci reveal that our topology is concordant with topologies reconstructed using the nuclear large subunit and mitochondrial small subunit ribosomal DNA markers, but the target capture datasets had much higher support values. We demonstrated how target capture approaches can effectively decipher ancient rapid radiations in cases where well resolved individual exon trees are sufficiently sampled and how to identify subsets of loci that are appropriate for fungal order-level phylogenetics.
IMA Fungus
Parmeliaceae is the largest family of lichen-forming fungi with a worldwide distribution. We used... more Parmeliaceae is the largest family of lichen-forming fungi with a worldwide distribution. We used a target enrichment data set and a qualitative selection method for 250 out of 350 genes to infer the phylogeny of the major clades in this family including 81 taxa, with both subfamilies and all seven major clades previously recognized in the subfamily Parmelioideae. The reduced genome-scale data set was analyzed using concatenated-based Bayesian inference and two different Maximum Likelihood analyses, and a coalescent-based species tree method. The resulting topology was strongly supported with the majority of nodes being fully supported in all three concatenated-based analyses. The two subfamilies and each of the seven major clades in Parmelioideae were strongly supported as monophyletic. In addition, most backbone relationships in the topology were recovered with high nodal support. The genus Parmotrema was found to be polyphyletic and consequently, it is suggested to accept the gen...
IMA Fungus
Draft genome assembly of Fusarium pilosicola Sequenced strain USA: Florida: Fort Pierce, 27.4467°... more Draft genome assembly of Fusarium pilosicola Sequenced strain USA: Florida: Fort Pierce, 27.4467° N; 80.3256° W, isolated from Bidens pilosa (NRRL 29124, CMWF 1183, PREM 63216-dried culture) (Yilmaz et al. 2021). Nucleotide sequence accession number This Whole Genome Shotgun project has been deposited at DDBJ/ENA/GenBank under the accession JAG-QDI000000000. The version described in this paper is version JAGQDI010000000. Materials and methods Fusarium pilosicola was grown on half strength potato dextrose agar (BD Difco ™) at 25 °C for 7 days after which genomic DNA was extracted as previously described (Möller et al. 1992). The DNA was then subjected to sequencing on the MinION sequencer (Oxford Nanopore Technologies) using a MinION flow cell (R10.3). The raw MinION data (coverage 178) was assembled into scaffolds using the Flye assembler (version 2.8.1) (Kolmogorov et al. 2019). The draft assembly was then subjected to
Biology Letters
The last Xerces blue butterfly was seen in the early 1940s, and its extinction is credited to hum... more The last Xerces blue butterfly was seen in the early 1940s, and its extinction is credited to human urban development. This butterfly has become a North American icon for insect conservation, but some have questioned whether it was truly a distinct species, or simply an isolated population of another living species. To address this question, we leveraged next-generation sequencing using a 93-year-old museum specimen. We applied a genome skimming strategy that aimed for the organellar genome and high-copy fractions of the nuclear genome by a shallow sequencing approach. From these data, we were able to recover over 200 million nucleotides, which assembled into several phylogenetically informative markers and the near-complete mitochondrial genome. From our phylogenetic analyses and haplotype network analysis we conclude that the Xerces blue butterfly was a distinct species driven to extinction.
IMA Fungus
ABSTRACTDraft genomes of the fungal species Ambrosiella cleistominuta, Cercospora brassicicola, C... more ABSTRACTDraft genomes of the fungal species Ambrosiella cleistominuta, Cercospora brassicicola, C. citrullina, Physcia stellaris, and Teratosphaeria pseudoeucalypti are presented. Physcia stellaris is an important lichen forming fungus and Ambrosiella cleistominuta is an ambrosia beetle symbiont. Cercospora brassicicola and C. citrullina are agriculturally relevant plant pathogens that cause leaf-spots in brassicaceous vegetables and cucurbits respectively. Teratosphaeria pseudoeucalypti causes severe leaf blight and defoliation of Eucalyptus trees. These genomes provide a valuable resource for understanding the molecular processes in these economically important fungi.
Genome Biology and Evolution
Lichen-forming fungi are known to produce a large number of secondary metabolites. Some metabolit... more Lichen-forming fungi are known to produce a large number of secondary metabolites. Some metabolites are deposited in the cortical layer of the lichen thallus where they exert important ecological functions, such as UV filtering. The fact that closely related lineages of lichen-forming fungi can differ in cortical chemistry suggests that natural product biosynthesis in lichens can evolve independent from phylogenetic constraints. Usnic acid is one of the major cortical pigments in lichens. Here we used a comparative genomic approach on 46 lichen-forming fungal species of the Lecanoromycetes to elucidate the biosynthetic gene content and evolution of the gene cluster putatively responsible for the biosynthesis of usnic acid. Whole-genome sequences were gathered from taxa belonging to different orders and families of Lecanoromycetes, where Parmeliaceae is the most well-represented taxon, and analyzed with a variety of genomic tools. The highest number of biosynthetic gene clusters was ...
Journal of Biogeography
This is the author manuscript accepted for publication and has undergone full peer review but has... more This is the author manuscript accepted for publication and has undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process, which may lead to differences between this version and the Version of Record. Please cite this article as
Xanthoparmelia (Parmeliaceae, Ascomycota) is the most species-rich genus of lichen-forming fungi.... more Xanthoparmelia (Parmeliaceae, Ascomycota) is the most species-rich genus of lichen-forming fungi. Species boundaries are based on morphological and chemical features, varying reproductive strategies and, more recently, molecular sequence data. The isidiate Xanthoparmelia mexicana group is common in arid regions of North and Central America and includes a range of morphological variation and variable secondary metabolites-salazinic or stictic acids mainly. In order to better understand the evolutionary history of this group and potential taxonomic implications, a molecular phylogeny representing 58 ingroup samples was reconstructed using four loci, including ITS, mtSSU, nuLSU rDNA and MCM7. Results indicate the existence of multiple, distinct lineages phenotypically agreeing with X. mexicana. One of these isidiate, salazinic acid-containing lineages is described here as a new species, X. pedregalensis sp. nov., including populations from xerophytic scrub vegetation in Pedregal de San Angel, Mexico City. X. mexicana s. str. is less isidiate than X. pedregalensis and has salazinic and consalazinic acid, occasionally with norstictic acid; whereas X. pedregalensis contains salazinic and norstictic acids and an unknown substance. Samples from the Old World, morphologically agreeing with X. mexicana, are only distantly related to X. mexicana s. str. Our results indicate that X. mexicana is likely less common than previously assumed and ongoing taxonomic revisions are required for isidiate Xanthoparmelia species.
Xanthoparmelia (Parmeliaceae, Ascomycota) is the most species-rich genus of lichen-forming fungi.... more Xanthoparmelia (Parmeliaceae, Ascomycota) is the most species-rich genus of lichen-forming fungi. Species boundaries are based on morphological and chemical features, varying reproductive strategies and, more recently, molecular sequence data. The isidiate Xanthoparmelia mexicana group is common in arid regions of North and Central America and includes a range of morphological variation and variable secondary metabolites-salazinic or stictic acids mainly. In order to better understand the evolutionary history of this group and potential taxonomic implications, a molecular phylogeny representing 58 ingroup samples was reconstructed using four loci, including ITS, mtSSU, nuLSU rDNA and MCM7. Results indicate the existence of multiple, distinct lineages phenotypically agreeing with X. mexicana. One of these isidiate, salazinic acid-containing lineages is described here as a new species, X. pedregalensis sp. nov., including populations from xerophytic scrub vegetation in Pedregal de San Angel, Mexico City. X. mexicana s. str. is less isidiate than X. pedregalensis and has salazinic and consalazinic acid, occasionally with norstictic acid; whereas X. pedregalensis contains salazinic and norstictic acids and an unknown substance. Samples from the Old World, morphologically agreeing with X. mexicana, are only distantly related to X. mexicana s. str. Our results indicate that X. mexicana is likely less common than previously assumed and ongoing taxonomic revisions are required for isidiate Xanthoparmelia species.
Lichens have traditionally been considered the symbiotic phenotype from the interactions of a sin... more Lichens have traditionally been considered the symbiotic phenotype from the interactions of a single fungal partner and one or few photosynthetic partners. However, the lichen symbiosis has been shown to be far more complex and may include a wide range of other interacting organisms, including non-photosynthetic bacteria, accessory fungi, and algae. In this study, we analyzed metagenomic shotgun sequences to better characterize lichen mycobiomes. Specifically, we inferred the range of fungi associated within lichen thalli from five groups of lichens – horsehair lichens (mycobiont=Bryoria spp.), shadow lichens (taxa in Physciaceae), rock posies (Rhizoplaca spp.), rock tripes (Umbilicaria spp.), and green rock shields (Xanthoparmelia spp.). Metagenomic reads from the multi-copy nuclear ribosomal internal transcribed spacer region, the standard DNA barcode region for fungi, were extracted, clustered, and used to infer taxonomic assignments. Our data revealed diverse lichen-associated m...
Scientific Reports
Advancements in molecular genetics have revealed that hybridization may be common among plants, a... more Advancements in molecular genetics have revealed that hybridization may be common among plants, animals, and fungi, playing a role in evolutionary dynamics and speciation. While hybridization has been well-documented in pathogenic fungi, the effects of these processes on speciation in fungal lineages with different life histories and ecological niches are largely unexplored. Here we investigated the potential influence of hybridization on the emergence of morphologically and reproductively distinct asexual lichens. We focused on vagrant forms (growing obligately unattached to substrates) within a clade of rock-dwelling, sexually reproducing species in the Rhizoplaca melanophthalma (Lecanoraceae, Ascomycota) species complex. We used phylogenomic data from both mitochondrial and nuclear genomes to infer evolutionary relationships and potential patterns of introgression. We observed multiple instances of discordance between the mitochondrial and nuclear trees, including the clade compr...
IMA Fungus
Dothideomycetes is the most diverse fungal class in Ascomycota and includes species with a wide r... more Dothideomycetes is the most diverse fungal class in Ascomycota and includes species with a wide range of lifestyles. Previous multilocus studies have investigated the taxonomic and evolutionary relationships of these taxa but often failed to resolve early diverging nodes and frequently generated inconsistent placements of some clades. Here, we use a phylogenomic approach to resolve relationships in Dothideomycetes, focusing on two genera of melanized, extremotolerant rock-inhabiting fungi, Lichenothelia and Saxomyces, that have been suggested to be early diverging lineages. We assembled phylogenomic datasets from newly sequenced (4) and previously available genomes (238) of 242 taxa. We explored the influence of tree inference methods, supermatrix vs. coalescent-based species tree, and the impact of varying amounts of genomic data. Overall, our phylogenetic reconstructions provide consistent and well-supported topologies for Dothideomycetes, recovering Lichenothelia and Saxomyces am...
MycoKeys
Xanthoparmelia(Parmeliaceae, Ascomycota) is the most species-rich genus of lichen-forming fungi. ... more Xanthoparmelia(Parmeliaceae, Ascomycota) is the most species-rich genus of lichen-forming fungi. Species boundaries are based on morphological and chemical features, varying reproductive strategies and, more recently, molecular sequence data. The isidiateXanthoparmeliamexicanagroup is common in arid regions of North and Central America and includes a range of morphological variation and variable secondary metabolites – salazinic or stictic acids mainly. In order to better understand the evolutionary history of this group and potential taxonomic implications, a molecular phylogeny representing 58 ingroup samples was reconstructed using four loci, including ITS, mtSSU, nuLSU rDNA and MCM7. Results indicate the existence of multiple, distinct lineages phenotypically agreeing withX.mexicana.One of these isidiate, salazinic acid-containing lineages is described here as a new species,X.pedregalensissp. nov., including populations from xerophytic scrub vegetation in Pedregal de San Angel, ...
Scientific Reports
In the age of next-generation sequencing, the number of loci available for phylogenetic analyses ... more In the age of next-generation sequencing, the number of loci available for phylogenetic analyses has increased by orders of magnitude. But despite this dramatic increase in the amount of data, some phylogenomic studies have revealed rampant gene-tree discordance that can be caused by many historical processes, such as rapid diversification, gene duplication, or reticulate evolution. We used a target enrichment approach to sample 400 single-copy nuclear genes and estimate the phylogenetic relationships of 13 genera in the lichen-forming family Lobariaceae to address the effect of data type (nucleotides and amino acids) and phylogenetic reconstruction method (concatenation and species tree approaches). Furthermore, we examined datasets for evidence of historical processes, such as rapid diversification and reticulate evolution. We found incongruence associated with sequence data types (nucleotide vs. amino acid sequences) and with different methods of phylogenetic reconstruction (species tree vs. concatenation). the resulting phylogenetic trees provided evidence for rapid and reticulate evolution based on extremely short branches in the backbone of the phylogenies. the observed rapid and reticulate diversifications may explain conflicts among gene trees and the challenges to resolving evolutionary relationships. Based on divergence times, the diversification at the backbone occurred near the Cretaceous-Paleogene (K-Pg) boundary (65 Mya) which is consistent with other rapid diversifications in the tree of life. Although some phylogenetic relationships within the Lobariaceae family remain with low support, even with our powerful phylogenomic dataset of up to 376 genes, our use of target-capturing data allowed for the novel exploration of the mechanisms underlying phylogenetic and systematic incongruence. With the advent of next-generation sequencing (NGS) technology, the evolutionary relationships of many groups on the tree of life are increasingly resolved and our understanding of the diversification of these groups has been significantly improved 1-3. However, in many groups, despite the use of NGS data, certain nodes have resisted unambiguous resolution. Conflicting topologies have been inferred from independent NGS data throughout the tree of life. For example, the placement of ctenophores and sponges have proven difficult as some studies place either sponges or ctenophores as sister to all other animals 4,5. Phylogenomic reconstructions of birds also yielded conflicting relationships for the earliest divergence within Neoaves 6 , perhaps due to inferences from unequal data and taxon sampling: 42 Mbp from 48 bird genomes 7 versus, 0.4 Mbp from 259 loci sampled from 198 species 8. In the plant kingdom, inferences from NGS datasets resolve Amborella either sister to all other angiosperms 9,10 or sister to water lilies 11,12. Similarly, the Gnetales may be sister to pines, all conifers, or all seed plants 13. Several reasons have been invoked to explain gene-tree discordance 14. Gene duplication can cause problems in phylogenetic reconstruction if paralogous loci with different histories are not distinguished within taxa and
Journal of Molluscan Studies
The Lichenologist
Species richness is not evenly distributed across the tree of life and a limited number of lineag... more Species richness is not evenly distributed across the tree of life and a limited number of lineages comprise an extraordinarily large number of species. In lichen-forming fungi, only two genera are known to be ‘ultradiverse’ (>500 species), with the most diverse genus, Xanthoparmelia, consisting of c. 820 species. While Australia and South Africa are known as current centres of diversity for Xanthoparmelia, it is not well known when and where this massive diversity arose. To better understand the geographical and temporal context of diversification in this diverse genus, we sampled 191 Xanthoparmelia specimens representing c. 124 species/species-level lineages from populations worldwide. From these specimens, we generated a multi-locus sequence data set using Sanger and high-throughput sequencing to reconstruct evolutionary relationships in Xanthoparmelia, estimate divergence times and reconstruct biogeographical histories in a maximum likelihood and Bayesian framework. This stud...
Genome Biology and Evolution, 2011
Using an independent fosmid cloning approach and comprehensive transcriptome analysis to compleme... more Using an independent fosmid cloning approach and comprehensive transcriptome analysis to complement data from the Selaginella moellendorffii genome project, we determined the complete mitochondrial genome structure of this spikemoss. Numerous recombination events mediated mainly via long sequence repeats extending up to 7kbp result in a complex mtDNA network structure. Peculiar features associated with the repeat sequences are more than 80 different microsatellite sites (predominantly trinucleotide motifs). The S. moellendorffii mtDNA encodes a plant-typical core set of a twin-arginine translocase (tatC), 17 respiratory chain subunits, and 2 rRNAs but lacks atp4 and any tRNA genes. As a further novelty among plant chondromes, the nad4L gene is encoded within an intron of the nad1 gene. A total of 37 introns occupying the 20 mitochondrial genes (four of which are disrupted into trans-splicing arrangements including two novel instances of transsplicing introns) make the S. moellendorffii chondrome the intron-richest and gene-poorest plant mtDNA known. Our parallel transcriptome analyses demonstrates functional splicing of all 37 introns and reveals a new record amount of plant organelle RNA editing with a total of 2,139 sites in mRNAs and 13 sites in the two rRNAs, all of which are exclusively of the C-to-U type.
Fungal Diversity
Rapid radiations in Fungi are only beginning to be studied with phylogenomic data. The evolutiona... more Rapid radiations in Fungi are only beginning to be studied with phylogenomic data. The evolutionary history of the lichenized fungal order Peltigerales has not been well resolved, particularly for the Collematineae. Here, we used concatenation and coalescent-based species tree methods to reconstruct the phylogeny of the Peltigerales based on sequences of 125 nuclear single-copy exon sequences among 60 samples, representing 58 species. Despite uneven, lineage-specific missing data and significant topological incongruence of individual exon trees, the resulting phylogenies were concordant and successfully resolved the phylogenetic relationships of the Peltigerales. Relationships in the Collematineae were defined by short branches and lower nodal support than in other parts of the tree, due in part to conflicting signal in exon trees, suggesting rapid diversification events in the early evolution of the suborder. Using tree distance measures, we were able to identify a minimum subset of exons that could reconstruct phylogenetic relationships in Peltigerales with higher support than the 125-exon dataset. Comparisons between the minimum and complete datasets in species tree inferences, bipartition analyses, and divergence time estimations displayed similar results, although the minimum dataset was characterized by higher levels of error in estimations of divergence times. Contrasting our inferences from the complete and minimum datasets to those derived from few nuclear and mitochondrial loci reveal that our topology is concordant with topologies reconstructed using the nuclear large subunit and mitochondrial small subunit ribosomal DNA markers, but the target capture datasets had much higher support values. We demonstrated how target capture approaches can effectively decipher ancient rapid radiations in cases where well resolved individual exon trees are sufficiently sampled and how to identify subsets of loci that are appropriate for fungal order-level phylogenetics.
IMA Fungus
Parmeliaceae is the largest family of lichen-forming fungi with a worldwide distribution. We used... more Parmeliaceae is the largest family of lichen-forming fungi with a worldwide distribution. We used a target enrichment data set and a qualitative selection method for 250 out of 350 genes to infer the phylogeny of the major clades in this family including 81 taxa, with both subfamilies and all seven major clades previously recognized in the subfamily Parmelioideae. The reduced genome-scale data set was analyzed using concatenated-based Bayesian inference and two different Maximum Likelihood analyses, and a coalescent-based species tree method. The resulting topology was strongly supported with the majority of nodes being fully supported in all three concatenated-based analyses. The two subfamilies and each of the seven major clades in Parmelioideae were strongly supported as monophyletic. In addition, most backbone relationships in the topology were recovered with high nodal support. The genus Parmotrema was found to be polyphyletic and consequently, it is suggested to accept the gen...
IMA Fungus
Draft genome assembly of Fusarium pilosicola Sequenced strain USA: Florida: Fort Pierce, 27.4467°... more Draft genome assembly of Fusarium pilosicola Sequenced strain USA: Florida: Fort Pierce, 27.4467° N; 80.3256° W, isolated from Bidens pilosa (NRRL 29124, CMWF 1183, PREM 63216-dried culture) (Yilmaz et al. 2021). Nucleotide sequence accession number This Whole Genome Shotgun project has been deposited at DDBJ/ENA/GenBank under the accession JAG-QDI000000000. The version described in this paper is version JAGQDI010000000. Materials and methods Fusarium pilosicola was grown on half strength potato dextrose agar (BD Difco ™) at 25 °C for 7 days after which genomic DNA was extracted as previously described (Möller et al. 1992). The DNA was then subjected to sequencing on the MinION sequencer (Oxford Nanopore Technologies) using a MinION flow cell (R10.3). The raw MinION data (coverage 178) was assembled into scaffolds using the Flye assembler (version 2.8.1) (Kolmogorov et al. 2019). The draft assembly was then subjected to
Biology Letters
The last Xerces blue butterfly was seen in the early 1940s, and its extinction is credited to hum... more The last Xerces blue butterfly was seen in the early 1940s, and its extinction is credited to human urban development. This butterfly has become a North American icon for insect conservation, but some have questioned whether it was truly a distinct species, or simply an isolated population of another living species. To address this question, we leveraged next-generation sequencing using a 93-year-old museum specimen. We applied a genome skimming strategy that aimed for the organellar genome and high-copy fractions of the nuclear genome by a shallow sequencing approach. From these data, we were able to recover over 200 million nucleotides, which assembled into several phylogenetically informative markers and the near-complete mitochondrial genome. From our phylogenetic analyses and haplotype network analysis we conclude that the Xerces blue butterfly was a distinct species driven to extinction.
IMA Fungus
ABSTRACTDraft genomes of the fungal species Ambrosiella cleistominuta, Cercospora brassicicola, C... more ABSTRACTDraft genomes of the fungal species Ambrosiella cleistominuta, Cercospora brassicicola, C. citrullina, Physcia stellaris, and Teratosphaeria pseudoeucalypti are presented. Physcia stellaris is an important lichen forming fungus and Ambrosiella cleistominuta is an ambrosia beetle symbiont. Cercospora brassicicola and C. citrullina are agriculturally relevant plant pathogens that cause leaf-spots in brassicaceous vegetables and cucurbits respectively. Teratosphaeria pseudoeucalypti causes severe leaf blight and defoliation of Eucalyptus trees. These genomes provide a valuable resource for understanding the molecular processes in these economically important fungi.
Genome Biology and Evolution
Lichen-forming fungi are known to produce a large number of secondary metabolites. Some metabolit... more Lichen-forming fungi are known to produce a large number of secondary metabolites. Some metabolites are deposited in the cortical layer of the lichen thallus where they exert important ecological functions, such as UV filtering. The fact that closely related lineages of lichen-forming fungi can differ in cortical chemistry suggests that natural product biosynthesis in lichens can evolve independent from phylogenetic constraints. Usnic acid is one of the major cortical pigments in lichens. Here we used a comparative genomic approach on 46 lichen-forming fungal species of the Lecanoromycetes to elucidate the biosynthetic gene content and evolution of the gene cluster putatively responsible for the biosynthesis of usnic acid. Whole-genome sequences were gathered from taxa belonging to different orders and families of Lecanoromycetes, where Parmeliaceae is the most well-represented taxon, and analyzed with a variety of genomic tools. The highest number of biosynthetic gene clusters was ...
Journal of Biogeography
This is the author manuscript accepted for publication and has undergone full peer review but has... more This is the author manuscript accepted for publication and has undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process, which may lead to differences between this version and the Version of Record. Please cite this article as
Xanthoparmelia (Parmeliaceae, Ascomycota) is the most species-rich genus of lichen-forming fungi.... more Xanthoparmelia (Parmeliaceae, Ascomycota) is the most species-rich genus of lichen-forming fungi. Species boundaries are based on morphological and chemical features, varying reproductive strategies and, more recently, molecular sequence data. The isidiate Xanthoparmelia mexicana group is common in arid regions of North and Central America and includes a range of morphological variation and variable secondary metabolites-salazinic or stictic acids mainly. In order to better understand the evolutionary history of this group and potential taxonomic implications, a molecular phylogeny representing 58 ingroup samples was reconstructed using four loci, including ITS, mtSSU, nuLSU rDNA and MCM7. Results indicate the existence of multiple, distinct lineages phenotypically agreeing with X. mexicana. One of these isidiate, salazinic acid-containing lineages is described here as a new species, X. pedregalensis sp. nov., including populations from xerophytic scrub vegetation in Pedregal de San Angel, Mexico City. X. mexicana s. str. is less isidiate than X. pedregalensis and has salazinic and consalazinic acid, occasionally with norstictic acid; whereas X. pedregalensis contains salazinic and norstictic acids and an unknown substance. Samples from the Old World, morphologically agreeing with X. mexicana, are only distantly related to X. mexicana s. str. Our results indicate that X. mexicana is likely less common than previously assumed and ongoing taxonomic revisions are required for isidiate Xanthoparmelia species.
Xanthoparmelia (Parmeliaceae, Ascomycota) is the most species-rich genus of lichen-forming fungi.... more Xanthoparmelia (Parmeliaceae, Ascomycota) is the most species-rich genus of lichen-forming fungi. Species boundaries are based on morphological and chemical features, varying reproductive strategies and, more recently, molecular sequence data. The isidiate Xanthoparmelia mexicana group is common in arid regions of North and Central America and includes a range of morphological variation and variable secondary metabolites-salazinic or stictic acids mainly. In order to better understand the evolutionary history of this group and potential taxonomic implications, a molecular phylogeny representing 58 ingroup samples was reconstructed using four loci, including ITS, mtSSU, nuLSU rDNA and MCM7. Results indicate the existence of multiple, distinct lineages phenotypically agreeing with X. mexicana. One of these isidiate, salazinic acid-containing lineages is described here as a new species, X. pedregalensis sp. nov., including populations from xerophytic scrub vegetation in Pedregal de San Angel, Mexico City. X. mexicana s. str. is less isidiate than X. pedregalensis and has salazinic and consalazinic acid, occasionally with norstictic acid; whereas X. pedregalensis contains salazinic and norstictic acids and an unknown substance. Samples from the Old World, morphologically agreeing with X. mexicana, are only distantly related to X. mexicana s. str. Our results indicate that X. mexicana is likely less common than previously assumed and ongoing taxonomic revisions are required for isidiate Xanthoparmelia species.
Lichens have traditionally been considered the symbiotic phenotype from the interactions of a sin... more Lichens have traditionally been considered the symbiotic phenotype from the interactions of a single fungal partner and one or few photosynthetic partners. However, the lichen symbiosis has been shown to be far more complex and may include a wide range of other interacting organisms, including non-photosynthetic bacteria, accessory fungi, and algae. In this study, we analyzed metagenomic shotgun sequences to better characterize lichen mycobiomes. Specifically, we inferred the range of fungi associated within lichen thalli from five groups of lichens – horsehair lichens (mycobiont=Bryoria spp.), shadow lichens (taxa in Physciaceae), rock posies (Rhizoplaca spp.), rock tripes (Umbilicaria spp.), and green rock shields (Xanthoparmelia spp.). Metagenomic reads from the multi-copy nuclear ribosomal internal transcribed spacer region, the standard DNA barcode region for fungi, were extracted, clustered, and used to infer taxonomic assignments. Our data revealed diverse lichen-associated m...
Scientific Reports
Advancements in molecular genetics have revealed that hybridization may be common among plants, a... more Advancements in molecular genetics have revealed that hybridization may be common among plants, animals, and fungi, playing a role in evolutionary dynamics and speciation. While hybridization has been well-documented in pathogenic fungi, the effects of these processes on speciation in fungal lineages with different life histories and ecological niches are largely unexplored. Here we investigated the potential influence of hybridization on the emergence of morphologically and reproductively distinct asexual lichens. We focused on vagrant forms (growing obligately unattached to substrates) within a clade of rock-dwelling, sexually reproducing species in the Rhizoplaca melanophthalma (Lecanoraceae, Ascomycota) species complex. We used phylogenomic data from both mitochondrial and nuclear genomes to infer evolutionary relationships and potential patterns of introgression. We observed multiple instances of discordance between the mitochondrial and nuclear trees, including the clade compr...
IMA Fungus
Dothideomycetes is the most diverse fungal class in Ascomycota and includes species with a wide r... more Dothideomycetes is the most diverse fungal class in Ascomycota and includes species with a wide range of lifestyles. Previous multilocus studies have investigated the taxonomic and evolutionary relationships of these taxa but often failed to resolve early diverging nodes and frequently generated inconsistent placements of some clades. Here, we use a phylogenomic approach to resolve relationships in Dothideomycetes, focusing on two genera of melanized, extremotolerant rock-inhabiting fungi, Lichenothelia and Saxomyces, that have been suggested to be early diverging lineages. We assembled phylogenomic datasets from newly sequenced (4) and previously available genomes (238) of 242 taxa. We explored the influence of tree inference methods, supermatrix vs. coalescent-based species tree, and the impact of varying amounts of genomic data. Overall, our phylogenetic reconstructions provide consistent and well-supported topologies for Dothideomycetes, recovering Lichenothelia and Saxomyces am...
MycoKeys
Xanthoparmelia(Parmeliaceae, Ascomycota) is the most species-rich genus of lichen-forming fungi. ... more Xanthoparmelia(Parmeliaceae, Ascomycota) is the most species-rich genus of lichen-forming fungi. Species boundaries are based on morphological and chemical features, varying reproductive strategies and, more recently, molecular sequence data. The isidiateXanthoparmeliamexicanagroup is common in arid regions of North and Central America and includes a range of morphological variation and variable secondary metabolites – salazinic or stictic acids mainly. In order to better understand the evolutionary history of this group and potential taxonomic implications, a molecular phylogeny representing 58 ingroup samples was reconstructed using four loci, including ITS, mtSSU, nuLSU rDNA and MCM7. Results indicate the existence of multiple, distinct lineages phenotypically agreeing withX.mexicana.One of these isidiate, salazinic acid-containing lineages is described here as a new species,X.pedregalensissp. nov., including populations from xerophytic scrub vegetation in Pedregal de San Angel, ...
Scientific Reports
In the age of next-generation sequencing, the number of loci available for phylogenetic analyses ... more In the age of next-generation sequencing, the number of loci available for phylogenetic analyses has increased by orders of magnitude. But despite this dramatic increase in the amount of data, some phylogenomic studies have revealed rampant gene-tree discordance that can be caused by many historical processes, such as rapid diversification, gene duplication, or reticulate evolution. We used a target enrichment approach to sample 400 single-copy nuclear genes and estimate the phylogenetic relationships of 13 genera in the lichen-forming family Lobariaceae to address the effect of data type (nucleotides and amino acids) and phylogenetic reconstruction method (concatenation and species tree approaches). Furthermore, we examined datasets for evidence of historical processes, such as rapid diversification and reticulate evolution. We found incongruence associated with sequence data types (nucleotide vs. amino acid sequences) and with different methods of phylogenetic reconstruction (species tree vs. concatenation). the resulting phylogenetic trees provided evidence for rapid and reticulate evolution based on extremely short branches in the backbone of the phylogenies. the observed rapid and reticulate diversifications may explain conflicts among gene trees and the challenges to resolving evolutionary relationships. Based on divergence times, the diversification at the backbone occurred near the Cretaceous-Paleogene (K-Pg) boundary (65 Mya) which is consistent with other rapid diversifications in the tree of life. Although some phylogenetic relationships within the Lobariaceae family remain with low support, even with our powerful phylogenomic dataset of up to 376 genes, our use of target-capturing data allowed for the novel exploration of the mechanisms underlying phylogenetic and systematic incongruence. With the advent of next-generation sequencing (NGS) technology, the evolutionary relationships of many groups on the tree of life are increasingly resolved and our understanding of the diversification of these groups has been significantly improved 1-3. However, in many groups, despite the use of NGS data, certain nodes have resisted unambiguous resolution. Conflicting topologies have been inferred from independent NGS data throughout the tree of life. For example, the placement of ctenophores and sponges have proven difficult as some studies place either sponges or ctenophores as sister to all other animals 4,5. Phylogenomic reconstructions of birds also yielded conflicting relationships for the earliest divergence within Neoaves 6 , perhaps due to inferences from unequal data and taxon sampling: 42 Mbp from 48 bird genomes 7 versus, 0.4 Mbp from 259 loci sampled from 198 species 8. In the plant kingdom, inferences from NGS datasets resolve Amborella either sister to all other angiosperms 9,10 or sister to water lilies 11,12. Similarly, the Gnetales may be sister to pines, all conifers, or all seed plants 13. Several reasons have been invoked to explain gene-tree discordance 14. Gene duplication can cause problems in phylogenetic reconstruction if paralogous loci with different histories are not distinguished within taxa and
Journal of Molluscan Studies
The Lichenologist
Species richness is not evenly distributed across the tree of life and a limited number of lineag... more Species richness is not evenly distributed across the tree of life and a limited number of lineages comprise an extraordinarily large number of species. In lichen-forming fungi, only two genera are known to be ‘ultradiverse’ (>500 species), with the most diverse genus, Xanthoparmelia, consisting of c. 820 species. While Australia and South Africa are known as current centres of diversity for Xanthoparmelia, it is not well known when and where this massive diversity arose. To better understand the geographical and temporal context of diversification in this diverse genus, we sampled 191 Xanthoparmelia specimens representing c. 124 species/species-level lineages from populations worldwide. From these specimens, we generated a multi-locus sequence data set using Sanger and high-throughput sequencing to reconstruct evolutionary relationships in Xanthoparmelia, estimate divergence times and reconstruct biogeographical histories in a maximum likelihood and Bayesian framework. This stud...