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Stuttgart Mühlhausen, Germany

Sohn J.-C.,University of Maryland University College | Regier J.C.,University of Maryland University College | Mitter C.,University of Maryland University College | Davis D.,Smithsonian Institution | And 3 more authors.
PLoS ONE | Year: 2013

Background: Yponomeutoidea, one of the early-diverging lineages of ditrysian Lepidoptera, comprise about 1,800 species worldwide, including notable pests and insect-plant interaction models. Yponomeutoids were one of the earliest lepidopteran clades to evolve external feeding and to extensively colonize herbaceous angiosperms. Despite the group's economic importance, and its value for tracing early lepidopteran evolution, the biodiversity and phylogeny of Yponomeutoidea have been relatively little studied. Methodology/Principal Findings: Eight nuclear genes (8 kb) were initially sequenced for 86 putative yponomeutoid species, spanning all previously recognized suprageneric groups, and 53 outgroups representing 22 families and 12 superfamilies. Eleven to 19 additional genes, yielding a total of 14.8 to 18.9 kb, were then sampled for a subset of taxa, including 28 yponomeutoids and 43 outgroups. Maximum likelihood analyses were conducted on data sets differing in numbers of genes, matrix completeness, inclusion/weighting of synonymous substitutions, and inclusion/exclusion of "rogue" taxa. Monophyly for Yponomeutoidea was supported very strongly when the 18 "rogue" taxa were excluded, and moderately otherwise. Results from different analyses are highly congruent and relationships within Yponomeutoidea are well supported overall. There is strong support overall for monophyly of families previously recognized on morphological grounds, including Yponomeutidae, Ypsolophidae, Plutellidae, Glyphipterigidae, Argyresthiidae, Attevidae, Praydidae, Heliodinidae, and Bedelliidae. We also assign family rank to Scythropiinae (Scythropiidae stat. rev.), which in our trees are strongly grouped with Bedelliidae, in contrast to all previous proposals. We present a working hypothesis of among-family relationships, and an informal higher classification. Host plant family associations of yponomeutoid subfamilies and families are non-random, but show no trends suggesting parallel phylogenesis. Our analyses suggest that previous characterizations of yponomeutoids as predominantly Holarctic were based on insufficient sampling. Conclusions/Significance: We provide the first robust molecular phylogeny for Yponomeutoidea, together with a revised classification and new insights into their life history evolution and biogeography. © 2013 Sohn et al.

Regier J.C.,University of Maryland University College | Regier J.C.,Institute for Bioscience and Biotechnology Research | Brown J.W.,U.S. Department of Agriculture | Mitter C.,University of Maryland University College | And 4 more authors.
PLoS ONE | Year: 2012

Background: Tortricidae, one of the largest families of microlepidopterans, comprise about 10,000 described species worldwide, including important pests, biological control agents and experimental models. Understanding of tortricid phylogeny, the basis for a predictive classification, is currently provisional. We present the first detailed molecular estimate of relationships across the tribes and subfamilies of Tortricidae, assess its concordance with previous morphological evidence, and re-examine postulated evolutionary trends in host plant use and biogeography. Methodology/Principal Findings: We sequenced up to five nuclear genes (6,633 bp) in each of 52 tortricids spanning all three subfamilies and 19 of the 22 tribes, plus up to 14 additional genes, for a total of 14,826 bp, in 29 of those taxa plus all 14 outgroup taxa. Maximum likelihood analyses yield trees that, within Tortricidae, differ little among data sets and character treatments and are nearly always strongly supported at all levels of divergence. Support for several nodes was greatly increased by the additional 14 genes sequenced in just 29 of 52 tortricids, with no evidence of phylogenetic artifacts from deliberately incomplete gene sampling. There is strong support for the monophyly of Tortricinae and of Olethreutinae, and for grouping of these to the exclusion of Chlidanotinae. Relationships among tribes are robustly resolved in Tortricinae and mostly so in Olethreutinae. Feeding habit (internal versus external) is strongly conserved on the phylogeny. Within Tortricinae, a clade characterized by eggs being deposited in large clusters, in contrast to singly or in small batches, has markedly elevated incidence of polyphagous species. The five earliest-branching tortricid lineages are all species-poor tribes with mainly southern/tropical distributions, consistent with a hypothesized Gondwanan origin for the family. Conclusions/Significance: We present the first robustly supported phylogeny for Tortricidae, and a revised classification in which all of the sampled tribes are now monophyletic. © 2012 Regier et al.

Konrad W.,University of Tubingen | Ebner M.,University of Tubingen | Traiser C.,University of Tubingen | Roth-Nebelsick A.,State Museum of Natural History
Pure and Applied Geophysics | Year: 2012

Wettability and retention capacity of leaf surfaces are parameters that contribute to interception of rain, fog or dew by forest canopies. Contrary to common expectation, hydrophobicity or wettability of a leaf do not dictate the stickiness of drops to leaves. Crucial for the adhesion of drops is the contact angle hysteresis, the difference between leading edge contact angle and trailing edge contact angle for a running drop. Other parameters that are dependent on the static contact angle are the maximum volume of drops that can stick to the surface and the persistence of an adhering drop with respect to evaporation. Adaption of contact angle and contact angle hysteresis allow one to pursue different strategies of drop control, for example efficient water shedding or maximum retention of adhering water. Efficient water shedding is achieved if contact angle hysteresis is low. Retention of (isolated) large drops requires a high contact angle hysteresis and a static contact angle of 65.5°, while maximum retention by optimum spacing of drops necessitates a high contact angle hysteresis and a static contact angle of 111.6°. Maximum persistence with respect to evaporation is obtained if the static contact angle amounts to 77.5°, together with a high contact angle hysteresis. It is to be expected that knowledge of these parameters can contribute to the capacity of a forest to intercept water. © 2011 Springer Basel AG.

News Article | January 25, 2016
Site: www.techtimes.com

Among hundreds of beetle specimens on display across Australian museums, many are still unidentified. Scientists recently discovered 24 new species of beetles belonging to the weevil genus Trigonopterus. In the study published online in the journal ZooKeys, German museum scientists Alexander Riedel and Rene Tänzler added the new species discovered from Australian rain forests to the weevil genus. "Usually a delay of decades or even centuries occurs between the encounter of a new species in the field and its thorough scientific study and formal naming," Riedel of the State Museum of Natural History Karlsruhe said. He added that there are only a few experts focusing on discovering new species and there are millions of unidentified insect species across museums around the globe. Only a small number of people are trained to identify these species. Most of the specimens were collected in the '80s and '90s and were kept in museums until the two scientists had the opportunity to study them. The scientists discovered that the newly described weevils are limited to small areas of rain forests in northern Queensland, Australia. They added that the reason why these species were not able to spread is perhaps their lack of wings. This prohibited the beetles from travelling and spreading. The beetles dwell mostly in the leaf litter, which makes them easily overlooked. "There are millions of species on our planet with whom we co-exist," Riedel said. "What's most exciting for me is to make a few of these new forms of life visible to others as well. And, of course, this has practical implications for national parks and so on, because if you realize that there are lots of species endemic to the region, then there is special value in protecting it," he added. The researchers suggest that a dense sampling of specimens with molecular data covering the east coast of Queensland and the northern part of New South Wales will help delineate species boundaries. "Thus, a solution of these taxonomic problems mainly depends on freshly collected material suitable for DNA sequencing," the researchers said. "The geographical ranges and ecologies of these 'difficult species' will become sufficiently clear with such a study, hopefully allowing the safe identification of all the unnamed specimens stored in museum collections," they added.

The university will use a $500,000 grant from the National Science Foundation to give students, researchers and the public access to the collection of Carl Rettenmeyer and his wife Marian. The collection includes about 2 million specimens of ants and other critters that also live in army ant colonies. The Department of Ecology & Evolutionary Biology, where Carl Rettenmeyer worked from 1971 to 1996, will begin digitally cataloging the dead insects this summer, creating an electronic database of the collection and research notes that will be available online. "We have bulk samples of many colonies, thousands of vials with preserved things in them, and quite a few cabinets with pinned insects in them as well," Jane O'Donnell, the biologist who is managing the collection, said Wednesday. The ant colonies also are documented in 5,000 Kodachrome slides and about 30 hours of digital videotape. O'Donnell said the idea is to make the work accessible to everyone from elementary school students to the world's top ant researchers. The school is planning two exhibits, one about the ants and another about the Rettenmeyers. Carl, who died in 2009, also founded the Connecticut State Museum of Natural History at UConn. The school plans to build a large-scale model of an army ant that will welcome visitors to school's biology and physics building. There also will be 4-foot-long model ants placed on the side of the building to publicize the collection. The Rettenmeyers painstakingly documented the complex life of foraging army ant colonies. They became the first to discover many of the other organisms that live there, such as a special mite that attaches to the end of an ant's leg and serves as a sort of hiking boot for the insect, O'Donnell said. The school expects the additional research on the ants will uncover new details about colony life. The collection, O'Donnell said, also will be a valuable source of DNA for those studying the history of ants and their symbiotic systems. "We don't even know what some of the relationships with some of these other organisms are," she said. "We're hoping that by putting all of these details together and making it easier to study, some patterns will emerge." The school hopes to have the initial exhibition ready by early 2017. "We share billions of years of evolutionary history with these organisms, and we don't even really have an accounting of what's on the planet with us yet," O'Donnell said. "That's part of this." Explore further: Ants get their place in Smithsonian exhibit

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