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Abstract: Phylogenetic hypotheses for the large cosmopolitan genus Hypericum (St. John’s wort) have previously been based on morphology, and molecular studies have thus far included only a few species. In this study, we used 360 sequences of the internal transcribed spacer (ITS) region of nuclear ribosomal DNA (nrDNA) for 206 species representing Hypericum (incl. Triadenum and Thornea) and three other genera of Hypericaceae to generate an explicit phylogenetic hypothesis for the genus using parsimony and model-based methods. The results indicate that the small genus Triadenum is nested in a clade within Hypericum containing most of the New World species. Sister to Hypericum is Thornea from Central America. Within Hypericum, three large clades and two smaller grades were found; these are based on their general morphology, especially characters used previously in taxonomy of the genus. Relative to the most recent classification, around 60% of the sections of Hypericum were monophyletic. We used a Bayesian approach to reconstruct ancestral states of selected morphological characters, which resulted in recognition of characters that support major clades within the genus and a revised interpretation of morphological evolution in Hypericum. The shrubby habit represents the plesiomorphic state from which herbs evolved several times. Arborescent species have radiated convergently in high-elevation habitats in tropical Africa and South America. [Copyright &y& Elsevier]

Abstract: Phylogenetic relationships in the genus Anthyllis (Leguminosae: Papilionoideae: Loteae) were investigated using data from the nuclear ribosomal internal transcribed spacer regions (ITS) and three plastid regions (psbA–trnH intergenic spacer, petB–petD region and rps16 intron). Bayesian and maximum parsimony (MP) analysis of a concatenated plastid dataset recovered well-resolved trees that are topologically similar, with many clades supported by unique indels. MP and Bayesian analyses of the ITS sequence data recovered trees that have several well-supported topological differences, both among analyses, and to trees inferred from the plastid data. The most substantial of these concerns A. vulneraria and A. lemanniana, whose placement in the parsimony analysis of the ITS data appears to be due to a strong long-branch effect. Analysis of the secondary structure of the ITS1 spacer showed a strong bias towards transitions in A. vulneraria and A. lemanniana, many of which were also characteristic of certain outgroup taxa. This may contribute to the conflicting placement of this clade in the MP tree for the ITS data. Additional conflicts between the plastid and ITS trees were more taxonomically focused. These differences may reflect the occurrence of reticulate evolution between closely related species, including a possible hybrid origin for A. hystrix. The patterns of incongruence between the plastid and the ITS data seem to correlate with taxon ranks. All of our phylogenetic analyses supported the monophyly of Anthyllis (incl. Hymenocarpos). Although they are often taxonomically associated with Anthyllis, the genera Dorycnopsis and Tripodion are shown here to be more closely related to other genera of Loteae. We infer up to six major clades in Anthyllis that are morphologically well-characterized, and which could be recognized as sections. Four of these agree with various morphology-based classifications, while the other two are novel. We reconstruct the evolution of several morphological characteristics found only in Anthyllis or tribe Loteae. Some of these characters support major clades, while others show evidence of homoplasy within Anthyllis. [Copyright &y& Elsevier]

Abstract: Ladybird beetles (family Coccinellidae) are a species-rich, ecologically diverse group of substantial agricultural significance, yet have been consistently problematic to classify, with evolutionary relationships poorly understood. In order to identify major clades within Coccinellidae, evaluate the current classification system, and identify likely drivers of diversification in this polyphagous group, we conducted the first simultaneous Bayesian analysis of morphological and multi-locus molecular data for any beetle family. Addition of morphological data significantly improved phylogenetic resolution and support for early diverging lineages, thereby better resolving evolutionary relationships than either data type alone. On the basis of these results, we formally recognize the subfamilies Microweisinae and Coccinellinae sensu. No significant support was found for the subfamilies Coccidulinae, Scymninae, Sticholotidinae, or Ortaliinae. Our phylogenetic results suggest that the evolutionary success of Coccinellidae is in large part attributable to the exploitation of ant-tended sternorrhynchan insects as a food source, enabled by the key innovation of unusual defense mechanisms in larvae. [Copyright &y& Elsevier]

The phylogeny of diploid species in the genus has been studied intensively. Although the origin of American polyploid species has been analyzed using multiple-copy internal transcribed spacer sequences, the origins of these species in Hordeum remain unclear. The objectives of our study were to elucidate the origins of American polyploid species and to explore phylogenetic relationships of these polyploids to diploid Hordeum and other diploid species in Triticeae using a single copy of a nuclear gene, disrupted meiotic cDNA1 ( DMC1). DMC1 sequences from nine Hordeum polyploid species were analyzed. Sequence comparisons revealed that one copy of sequences from polyploid species , , and showed a 82 bp miniature inverted-repeat terminal element (MITE) ( Stowaway) insertion, which was also detected in the Triticeae diploid species species (W genome) and (Ta genome). Maximum parsimony and Bayesian analysis suggested that diploid subsp. is one ancestor of polyploids , H. brachyantherum subsp. , , and . The other ancestor of tetraploid H. depressum is probably . Hordeum cordobense was suggested to be one of the genome donors to hexaploid H. procerum. The diploid and tetraploid H. tetraploidum were suggested as the parents to hexaploid species . The result is that one sequence from each of three Hordeum tetrapolyploids, including H. fuegianum, H. jubatum, and H. tetraploidum, and one from Hordeum hexaploid H. arizonicum fall outside the Hordeum clade of the DMC1 phylogenetic tree, therefore representing another example of complex evolutionary history. Our data may shed light on future phylogenetic studies in Triticeae, especially for the polyploids, by broadening the scope of investigations through sampling more genome types in Poaceae, not only from the tribe Triticeae. [ABSTRACT FROM AUTHOR]

Abstract: The genus Lygodactylus is a group of small, diurnal geckos distributed mainly in Africa and Madagascar. A closely related, monotypic genus is Microscalabotes from Madagascar. We examined fragments of two moderate- to slow-evolving nuclear genes (RAG-1, RAG-2) and of two fast-evolving mitochondrial genes (16SrRNA, cytochrome b) to estimate phylogenetic relationships among 28 (of about 60) species (including Microscalabotes). Since cytochrome b provided little resolution for analysis of interspecific relationships in Lygodactylus, it was excluded from the concatenated Bayesian analysis. Our well-resolved Bayesian inference tree and its resulting clades confirm many previously suggested relationships among dwarf geckos based mainly on morphological characters, while several novel relationships lead us to regroup some species and to synonymize the genus Microscalabotes with the genus Lygodactylus. Our phylogenetic analysis well supports the monophyly of Lygodactylus (including Microscalabotes). However, it rejects monophyly of the Madagascan Lygodactylus. On the other hand, the data do not reject monophyly of the African forms. Though Africa is currently the main centre of diversity of Lygodactylus, our data suggest that the most parsimonious scenario would be a Madagascan origin, one dispersal to Africa, and one back to Madagascar. [Copyright &y& Elsevier]

Abstract: A reconstruction of phylogenetic relationships based on three chloroplast DNA markers comprising 98 species of the genus Potentilla and 15 additional genera from the tribe Potentilleae (Rosaceae) is presented. The phylogeny supported the current generic concept of the subtribe Fragariinae and resolved major lineages within the subtribe Potentillinae. Resolved lineages corresponded to the combined genera Argentina, Piletophyllum, and Tylosperma, an European and Asian group of species approximately equivalent to the Trichocarpae Herbaceae sensu Th. Wolf, the series Tormentillae Th. Wolf, a North American clade comprising the genera Horkelia, Horkeliella, and Ivesia, the species Potentilla fragarioides and P. freyniana, and to a taxonomically highly diverse but molecularly little diverged core group of Potentilla, respectively. Age estimates of phylogenetic splits resolved in the Potentilleae using Bayesian inference, suggested a diversification of the tribe in the Eocene and radiation of two major evolutionary lineages corresponding to the Fragariinae and Potentillinae at approximately comparable times. Ancestral area reconstructions based on the recent distribution ranges of species and collection sites of cpDNA haplotypes suggested an Asian origin for Potentilla s.str., and explained the arrival of this still informal taxon in Europe and particularly North America by multiple dispersal events. In combining the phylogenetic and geographic data with molecularly inferred time estimates and taxonomy, strongly contrasting evolutionary patterns were identified. These evolutionary patterns included rapid speciation on a continental and worldwide scale accompanied by multiple intercontinental dispersals opposed to largely diverged lineages of limited taxonomic diversity and vicariant geographic distribution. The molecular-based phylogeographic hypothesis finally is discussed on the background of the fossil record of Potentilla. [Copyright &y& Elsevier]

Abstract: The Osmiini (Megachilidae) constitute a taxonomically and biologically diverse tribe of bees. To resolve their generic and suprageneric relationships, we inferred a phylogeny based on three nuclear genes (Elongation factor 1-α, LW-rhodopsin and CAD) applying both parsimony and Bayesian methods. Our phylogeny, which includes 95 osmiine species representing 18 of the 19 currently recognized genera, is well resolved with high support for most basal nodes. The core osmiine genera were found to form a well-supported monophyletic group, but four small genera, Noteriades, Afroheriades, Pseudoheriades and possibly Ochreriades, formerly included in the Osmiini, do not appear to belong within this tribe. Our phylogeny results in the following taxonomic changes: Stenosmia and Hoplosmia are reduced to subgeneric rank in Hoplitis and Osmia, respectively, Micreriades is recognized as a subgenus in Hoplitis and the subgenus Nasutosmia is transferred from Hoplitis to Osmia. We inferred a biogeographic scenario for the Osmiini applying maximum likelihood inference and models of character evolution. We provide evidence that the Osmiini originated in the Palearctic, and that extensive exchanges occurred between the Palearctic and the Nearctic. The latter finding may relate to the fact that many osmiine species nest in wood or in stems, facilitating dispersal by overseas transport of the nests. [Copyright &y& Elsevier]

This article presents a study regarding the molecular phylogeny, natural delineation, and floral evolution in Campanula. Independent and combined data from nuclear and chloroplast sequences were analyzed with parsimony and Bayesian methods to explore the biological processes that occurred during the evolution of this genus.

The article examines the monophyly of Cestrum section Habrothammus and its relationships with other sections of Cestrum. Phylogenetic analysis of DNA sequences from chloroplast regions and nuclear ribosomal ITS of Cestrum shows a very low molecular divergence indicating a rapid diversification in Cestrum. Using the parsimony and Bayesian analyses, the monophyly of the Cestrum sections was rejected including the sect. Habrothammus. Revision on the infrageneric classifications is recommended.