Hyaenodonta is a diverse clade of carnivorous mammals that were part of terrestrial faunas in the Paleogene of Eurasia and North America, but the oldest record for the group is Afro-Arabian, making the record there vital for understanding the evolution of this wide-spread group. Previous studies show an ancient split between two major clades of hyaenodonts that converged in hypercarnivory: Hyainailourinae and Hyaenodontinae. These clades are each supported by cranial characters. Phylogenetic analyses of hyaenodonts also support the monophyly of Teratodontinae, an Afro-Arabian clade of mesocarnivorous to hypercarnivorous hyaenodonts. Unfortunately, the cranial anatomy of teratodontines is poorly known, and aligning the clade with other lineages has been difficult. Here, a new species of the phylogenetically controversial teratodontine Masrasector is described from Locality 41 (latest Priabonian, late Eocene) from the Fayum Depression, Egypt. The hypodigm includes the most complete remains of a Paleogene teratodontine, including largely complete crania, multiple dentaries, and isolated humeri. Standard and “tip-dating” Bayesian analyses of a character-taxon matrix that samples cranial, postcranial, and dental characters support a monophyletic Masrasector within Teratodontinae, which is consistently placed as a close sister group of Hyainailouridae. The cranial morphology of Masrasector provides new support for an expanded Hyainailouroidea (Teratodontinae + Hyainailouridae), particularly characters of the nuchal crest, palate, and basicranium. A discriminant function analysis was performed using measurements of the distal humerus from a diverse sample of extant carnivorans to infer the locomotor habits of Masrasector. Masrasector was assigned to the “terrestrial” locomotor category, a result consistent with the well-defined medial trochlear ridges, and moderately developed supinator crests of the specimens. Masrasector appears to have been a fast-moving terrestrial form with a diverse diet. These specimens considerably improve our understanding of Teratodontinae, an ancient member of the Afro-Arabian mammalian fauna, and our understanding of hyaenodont diversity before the dispersal of Carnivora to the continent near the end of the Paleogene.
Rhizaria is one of the six supergroups of eukaryotes, which comprise the majority of amoeboid and skeleton-building protists living in freshwater and marine ecosystems. There is an overall lack of molecular data for the group and therefore the deep phylogeny of rhizarians is unresolved. Molecular data are particularly scarce for the clade of Retaria, which include two prominent groups of microfossils: foraminiferans and radiolarians. To fill this gap, we have produced and sequenced EST libraries for 14 rhizarian species including seven foraminiferans, Gromia and six taxa belonging to traditional Haeckel’s Radiolaria: Acantharea, Polycystinea, and Phaeodarea. A matrix was constructed for phylogenetic analysis based on 109 genes and a total of 56 species, of which 22 are rhizarians. Our analyses provide the first multigene evidence for branching of Phaeodarea within Cercozoa, confirming the polyphyly of Haeckel’s Radiolaria. It confirms the monophyly of Retaria, a clade grouping Foraminifera with other lineages of Radiolaria. However, contrary to what could be expected from morphological observations, Foraminifera do not form a sister group to radiolarians, but branch within them as sister to either Acantharea or Polycystinea depending on the multigene data set. While the monophyly of Foraminifera and Acantharea is well supported, that of Polycystinea, represented in our data by Spumellaria and Collodaria is questionable. In view of our study, Haeckel’s Radiolaria appears as both, a polyphyletic and paraphyletic assemblage of independent groups that should be considered as separate lineages in protist classification.
Results of a study on species of Inocybe section Rimosae sensu lato in Utah are presented. Eight species, seven from the Pseudosperma clade (section Rimosae sensu stricto) and one from the Inosperma clade (section Rimosae pro parte), are documented morphologically and phylogenetically. Five of the eight species, I. aestiva, I. breviterincarnata, I. cercocarpi, I. niveivelata and I. occidentalis-all members of the Pseudosperma clade-are described as new from Utah and other western states. Two European species, I. spuria and I. obsoleta, are confirmed from Utah. Inocybe aurora, originally described from Nova Scotia, is synonymized with I. obsoleta. The only member of the Inosperma clade recorded from Utah is I. lanatodisca, a widely distributed species for which three geographical clusters were detected. The phylogenetic analyses indicate that the Pseudosperma clade includes 53 clusters or species worldwide and that the Inosperma clade includes 47 such clusters. Many of these probably correspond to undescribed species. A key to species of section Rimosae sensu lato from Utah is provided together with illustrations of the eight species found in the state.
Pyronemataceae is the largest and most heterogeneous family of Pezizomycetes. It is morphologically and ecologically highly divers, comprising saprobic, ectomycorrhizal, bryosymbiotic and parasitic species, occurring in a broad range of habitats (on soil, burnt ground, debris, wood, dung and inside living bryophytes, plants and lichens). To assess the monophyly of Pyronemataceae and provide a phylogenetic hypothesis of the group, we compiled a 4-gene dataset including one nuclear ribosomal and three protein-coding genes for 132 distinct Pezizomycetes species (4437 nucleotides with all markers available for 80% of the total 142 included taxa). This is the most comprehensive molecular phylogeny of Pyronemataceae, and Pezizomycetes, to date. Three hundred ninety four new sequences were generated during this project, with the following numbers for each gene: RPB1 (124), RPB2 (99), EF-1α (120) and LSU rDNA (51). The dataset includes 93 unique species from 40 genera of Pyronemataceae, and 34 species from 25 genera representing an additional 12 families of the class. Parsimony, maximum likelihood and Bayesian analyses suggest that Pyronemataceae is paraphyletic due to the nesting of both Ascodesmidaceae and Glaziellaceae within the family. Four lineages with taxa currently classified in the family, the Boubovia, Geopyxis, Pseudombrophila and Pulvinula lineages, form a monophyletic group with Ascodemidaceae and Glaziellaceae. We advocate the exclusion of these four lineages in order to recognize a monophyletic Pyronemataceae. The genus Coprotus (Thelebolales, Leotiomycetes) is shown to belong to Pezizomycetes, forming a strongly supported monophyletic group with Boubovia. Ten strongly supported lineages are identified within Pyronemataceae s. str. Of these, the Pyropyxis and Otidea lineages are identified as successive sister lineages to the rest of Pyronemataceae s. str. The highly reduced (gymnohymenial) Monascella is shown to belong to Pezizomycetes and is for the first time suggested to be closely related to the cleistothecial Warcupia, as a sister group to the primarily apothecial Otidea. None of the lineages of pyronemataceous taxa identified here correspond to previous families or subfamily classifications. Ancestral character state reconstructions (ASR) using a Bayesian approach support that the ancestors of Pezizomycetes and Pyronemataceae were soil inhabiting and saprobic. Ectomycorrhizae have arisen within both lineages A, B and C of Pezizomycetes and are suggested to have evolved independently seven to eight times within Pyronemataceae s.l., whereas an obligate bryosymbiotic lifestyle has arisen only twice. No reversals to a free-living, saprobic lifestyle have happened from symbiotic or parasitic Pyronemataceae. Specializations to various substrates (e.g. burnt ground and dung) are suggested to have occurred several times in mainly saprobic lineages. Although carotenoids in the apothecia are shown to have arisen at least four times in Pezizomycetes, the ancestor of Pyronemataceae s. str., excluding the Pyropyxis and Otidea lineages, most likely produced carotenoids, which were then subsequently lost in some clades (- and possibly gained again). Excipular hairs were found with a high probability to be absent from apothecia in the deepest nodes of Pezizomycetes and in the ancestor of Pyronemataceae s. str. True hairs are restricted to the core group of Pyronemataceae s. str., but are also found in Lasiobolus (Ascodesmidaceae), the Pseudombrophila lineage and the clade of Chorioactidaceae, Sarcoscyphaceae and Sarcosomataceae. The number of gains and losses of true hairs within Pyronemataceae s.str., however, remains uncertain. The ASR of ascospore guttulation under binary coding (present or absent) indicates that this character is fast evolving and prone to shifts.
Habenaria is a large genus of terrestrial orchids distributed throughout the tropical and subtropical regions of the world. The integrity and monophyly of this genus have been under discussion for many years, and at one time or another, several genera have been either included in a broadly defined Habenaria or segregated from it. In this study, the phylogenetic relationships of the Neotropical members of the genus and selected groups of African Habenaria were investigated using DNA sequences from the nuclear internal transcribed spacer (ITS) region and the plastid matK gene sampled from 151 taxa of Habenaria from the Neotropics (ca. 51% of the total) as well as 20 species of Habenaria and Bonatea from the Old World. Bayesian and parsimony trees were congruent with each other, and in all analyses, the Neotropical species formed a highly supported group. African species of Habenaria in sections Dolichostachyae, Podandria, Diphyllae, Ceratopetalae and Bilabrellae, and the Neotropical clade formed a highly supported “core Habenaria clade”, which includes the type species of the genus from the New World. The topology of the trees indicates an African origin for the Neotropical clade and the low sequence divergence among the Neotropical species suggests a recent radiation of the genus in the New World. Species of Bonatea and Habenaria sections Chlorinae and Multipartitae formed a well-supported clade that was sister to the “core Habenaria clade”. The Neotropical clade consists of at least 21 well-supported subgroups, but all Neotropical sections of the current sectional classification are paraphyletic or polyphyletic and will need extensive revision and recircumscription. Most of the Neotropical subgroups formed morphologically uniform assemblage of species, but some cases of morphological divergence within subgroups and convergence between subgroups indicated that morphology alone can be misleading for inferring relationships within the genus. The genera Bertauxia, Kusibabella and Habenella, segregated from New World Habenaria, are not monophyletic and a revision of the sectional classification rather than a generic division seems most appropriate. Our results do not support an extensive generic fragmentation of Habenaria as previously suggested and will provide a framework for revising the infrageneric classification and investigating the patterns of morphological evolution and geographical distribution of the genus in the New World.
Assassin bugs are one of the most successful clades of predatory animals based on their species numbers (∼6,800 spp.) and wide distribution in terrestrial ecosystems. Various novel prey capture strategies and remarkable prey specializations contribute to their appeal as a model to study evolutionary pathways involved in predation. Here, we reconstruct the most comprehensive reduviid phylogeny (178 taxa, 18 subfamilies) to date based on molecular data (5 markers). This phylogeny tests current hypotheses on reduviid relationships emphasizing the polyphyletic Reduviinae and the blood-feeding, disease-vectoring Triatominae, and allows us, for the first time in assassin bugs, to reconstruct ancestral states of prey associations and microhabitats. Using a fossil-calibrated molecular tree, we estimated divergence times for key events in the evolutionary history of Reduviidae. Our results indicate that the polyphyletic Reduviinae fall into 11-14 separate clades. Triatominae are paraphyletic with respect to the reduviine genus Opisthacidius in the maximum likelihood analyses; this result is in contrast to prior hypotheses that found Triatominae to be monophyletic or polyphyletic and may be due to the more comprehensive taxon and character sampling in this study. The evolution of blood-feeding may thus have occurred once or twice independently among predatory assassin bugs. All prey specialists evolved from generalist ancestors, with multiple evolutionary origins of termite and ant specializations. A bark-associated life style on tree trunks is ancestral for most of the lineages of Higher Reduviidae; living on foliage has evolved at least six times independently. Reduviidae originated in the Middle Jurassic (178 Ma), but significant lineage diversification only began in the Late Cretaceous (97 Ma). The integration of molecular phylogenetics with fossil and life history data as presented in this paper provides insights into the evolutionary history of reduviids and clears the way for in-depth evolutionary hypothesis testing in one of the most speciose clades of predators.
Over the past two decades numerous new trees of modern human populations have been published extensively but little attention has been paid to formal phylogenetic synthesis. We utilized the “matrix representation with parsimony” (MRP) method to infer a composite phylogeny (supertree) of modern human populations, based on 257 genetic/genomic, as well as linguistic, phylogenetic trees and 44 admixture plots from 200 published studies (1990-2014). The resulting supertree topology includes the most basal position of S African Khoisan followed by C African Pygmies, and the paraphyletic section of all other sub-Saharan peoples. The sub-Saharan African section is basal to the monophyletic clade consisting of the N African-W Eurasian assemblage and the consistently monophyletic Eastern superclade (Sahul-Oceanian, E Asian, and Beringian-American peoples). This topology, dominated by genetic data, is well-resolved and robust to parameter set changes, with a few unstable areas (e.g., West Eurasia, Sahul-Melanesia) reflecting the existing phylogenetic controversies. A few populations were identified as highly unstable “wildcard taxa” (e.g. Andamanese, Malagasy). The linguistic classification fits rather poorly on the supertree topology, supporting a view that direct coevolution between genes and languages is far from universal.
A frequent bottleneck in interpreting phylogenomic output is the need to screen often thousands of trees for features of interest, particularly robust clades of specific taxa, as evidence of monophyletic relationship and/or reticulated evolution. Here we present PhySortR, a fast, flexible R package for classifying phylogenetic trees. Unlike existing utilities, PhySortR allows for identification of both exclusive and non-exclusive clades uniting the target taxa based on tip labels (i.e., leaves) on a tree, with customisable options to assess clades within the context of the whole tree. Using simulated and empirical datasets, we demonstrate the potential and scalability of PhySortR in analysis of thousands of phylogenetic trees without a priori assumption of tree-rooting, and in yielding readily interpretable trees that unambiguously satisfy the query. PhySortR is a command-line tool that is freely available and easily automatable.
Flatfish cranial asymmetry represents one of the most remarkable morphological innovations among vertebrates, and has fueled vigorous debate on the manner and rate at which strikingly divergent phenotypes evolve. A surprising result of many recent molecular phylogenetic studies is the lack of support for flatfish monophyly, where increasingly larger DNA datasets of up to 23 loci have either yielded a weakly supported flatfish clade or indicated the group is polyphyletic. Lack of resolution for flatfish relationships has been attributed to analytical limitations for dealing with processes such as nucleotide non-stationarity and incomplete lineage sorting (ILS). We tackle this phylogenetic problem using a sequence dataset comprising more than 1,000 ultraconserved DNA element (UCE) loci covering 45 carangimorphs, the broader clade containing flatfishes and several other specialized lineages such as remoras, billfishes, and archerfishes.
Evolutionary relationships among birds in Neoaves, the clade comprising the vast majority of avian diversity, have vexed systematists due to the ancient, rapid radiation of numerous lineages. We applied a new phylogenomic approach to resolve relationships in Neoaves using target enrichment (sequence capture) and high-throughput sequencing of ultraconserved elements (UCEs) in avian genomes. We collected sequence data from UCE loci for 32 members of Neoaves and one outgroup (chicken) and analyzed data sets that differed in their amount of missing data. An alignment of 1,541 loci that allowed missing data was 87% complete and resulted in a highly resolved phylogeny with broad agreement between the Bayesian and maximum-likelihood (ML) trees. Although results from the 100% complete matrix of 416 UCE loci were similar, the Bayesian and ML trees differed to a greater extent in this analysis, suggesting that increasing from 416 to 1,541 loci led to increased stability and resolution of the tree. Novel results of our study include surprisingly close relationships between phenotypically divergent bird families, such as tropicbirds (Phaethontidae) and the sunbittern (Eurypygidae) as well as between bustards (Otididae) and turacos (Musophagidae). This phylogeny bolsters support for monophyletic waterbird and landbird clades and also strongly supports controversial results from previous studies, including the sister relationship between passerines and parrots and the non-monophyly of raptorial birds in the hawk and falcon families. Although significant challenges remain to fully resolving some of the deep relationships in Neoaves, especially among lineages outside the waterbirds and landbirds, this study suggests that increased data will yield an increasingly resolved avian phylogeny.