Out of taxonomic crypsis: A new trans-arctic cryptic species pair corroborated by phylogenetics and molecular evidence.

Cryptic species are a common phenomenon in cosmopolitan marine species. The use of molecular tools has often uncovered cryptic species occupying a fraction of the geographic range of the original morphospecies. Shipworms (Teredinidae) are marine bivalves, living in drift and fixed wood, many of which have a conserved morphology across cosmopolitan distributions. Herein novel and GenBank mitochondrial (cytochrome c oxidase subunit I) and nuclear (18S rRNA) DNA sequences are employed to produce a phylogeny of the Teredinidae and delimit a cryptic species pair in the Psiloteredo megotara complex. The anatomy, biogeography, and ecology of P. megotara, Psiloteredo sp. and Nototeredo edax are compared based on private and historic museum collections and a thorough literature review. Morphological and anatomical characters of P. megotara from the North Atlantic and Psiloteredo sp. from Japan were morphologically indistinguishable, and differ in pallet architecture and soft tissue anatomy from N. edax. The two Psiloteredo species were then delimited as genetically distinct species using four molecular-based methods. Consequently, the Northwest Pacific species, Psiloteredo pentagonalis, first synonymized with N. edax and then with P. megotara, is resurrected. Nototeredo edax, P. megotara and P. pentagonalis are redescribed based upon morphological and molecular characters. Phylogenetic analysis further revealed cryptic species complexes within the cosmopolitan species Bankia carinata and possibly additional cryptic lineages within the cosmopolitan Lyrodus pedicellatus.

Fire in Australian savannas: from leaf to landscape.

Savanna ecosystems comprise 22% of the global terrestrial surface and 25% of Australia (almost 1.9 million km2) and provide significant ecosystem services through carbon and water cycles and the maintenance of biodiversity. The current structure, composition and distribution of Australian savannas have coevolved with fire, yet remain driven by the dynamic constraints of their bioclimatic niche. Fire in Australian savannas influences both the biophysical and biogeochemical processes at multiple scales from leaf to landscape. Here, we present the latest emission estimates from Australian savanna biomass burning and their contribution to global greenhouse gas budgets. We then review our understanding of the impacts of fire on ecosystem function and local surface water and heat balances, which in turn influence regional climate. We show how savanna fires are coupled to the global climate through the carbon cycle and fire regimes. We present new research that climate change is likely to alter the structure and function of savannas through shifts in moisture availability and increases in atmospheric carbon dioxide, in turn altering fire regimes with further feedbacks to climate. We explore opportunities to reduce net greenhouse gas emissions from savanna ecosystems through changes in savanna fire management.

Image-based recognition of parasitoid wasps using advanced neural networks.

Hymenoptera has some of the highest diversity and number of individuals among insects. Many of these species potentially play key roles as food sources, pest controllers and pollinators. However, little is known about the diversity and biology and ~80% of the species have not yet been described. Classical taxonomy based on morphology is a rather slow process but DNA barcoding has already brought considerable progress in identification. Innovative methods such as image-based identification and automation can further speed up the process. We present a proof of concept for image data recognition of a parasitic wasp family, the Diapriidae (Hymenoptera), obtained as part of the GBOL III project. These tiny (1.2-4.5mm) wasps were photographed and identified using DNA barcoding to provide a solid ground truth for training a neural network. Taxonomic identification was used down to the genus level. Subsequently, three different neural network architectures were trained, evaluated and optimised. As a result, 11 different genera of diaprids and one mixed group of 'other Hymenoptera' can be classified with an average accuracy of 96%. Additionally, the sex of the specimen can be classified automatically with an accuracy of >97%.

Scratching the tip of the iceberg: integrative taxonomy reveals 30 new species records of Microgastrinae (Braconidae) parasitoid wasps for Germany, including new Holarctic distributions.

Substantial parts of the European and German insect fauna still remain largely unexplored, the so-called "dark taxa". In particular, midges (Diptera) and parasitoid wasps (Hymenoptera) are abundant and species-rich throughout Europe, yet are often neglected in biodiversity research. One such dark taxon is Microgastrinae wasps (Hymenoptera: Braconidae), a group of parasitoids of lepidopteran caterpillars with 252 species reported in Germany so far. As part of the German Barcode of Life Project GBOL III: Dark Taxa, reverse DNA barcoding and integrative taxonomic approaches were used to shed some light on the German Fauna of Microgastrinae wasps. In our workflow, DNA barcoding was used for molecular clustering of our specimens in a first step, morphological examination of the voucher specimens in a second step, and host data compared in a third step. Here, 30 species are reported for the first time in Germany, adding more than 10% to the known German fauna. Information for four species is provided in a new Holarctic context, reporting them for the Nearctic or, respectively, Palaearctic region, and 26 additional country records are added from sequenced material available in the collections accessible to us. Molecular clusters that show signs of discrepancies are discussed. Results show that we are just scratching the tip of the iceberg of the unexplored Microgastrinae diversity in Germany.

First insights into the biodiversity and biogeography of the Southern Ocean deep sea.

Shallow marine benthic communities around Antarctica show high levels of endemism, gigantism, slow growth, longevity and late maturity, as well as adaptive radiations that have generated considerable biodiversity in some taxa. The deeper parts of the Southern Ocean exhibit some unique environmental features, including a very deep continental shelf and a weakly stratified water column, and are the source for much of the deep water in the world ocean. These features suggest that deep-sea faunas around the Antarctic may be related both to adjacent shelf communities and to those in other oceans. Unlike shallow-water Antarctic benthic communities, however, little is known about life in this vast deep-sea region. Here, we report new data from recent sampling expeditions in the deep Weddell Sea and adjacent areas (748-6,348 m water depth) that reveal high levels of new biodiversity; for example, 674 isopods species, of which 585 were new to science. Bathymetric and biogeographic trends varied between taxa. In groups such as the isopods and polychaetes, slope assemblages included species that have invaded from the shelf. In other taxa, the shelf and slope assemblages were more distinct. Abyssal faunas tended to have stronger links to other oceans, particularly the Atlantic, but mainly in taxa with good dispersal capabilities, such as the Foraminifera. The isopods, ostracods and nematodes, which are poor dispersers, include many species currently known only from the Southern Ocean. Our findings challenge suggestions that deep-sea diversity is depressed in the Southern Ocean and provide a basis for exploring the evolutionary significance of the varied biogeographic patterns observed in this remote environment.

Discovery of the primary aphid (Hemiptera: Aphidomorpha) and scale insect (Hemiptera: Coccomorpha) type specimens from the collection of Theodor Hartig (18051880).

Theodor Hartigs aphid and scale insect type specimens have been presumed lost or destroyed for the last 140 years. Here we document their discovery at the Bavarian State Collection of Zoology (Zoologische Staatssammlung Mnchen, ZSM), in Munich, Germany. These specimens include primary types for 24 aphid, three adelgid, and two armored scale insect species named by Hartig between 1834 and 1851, as well as other specimens of unknown importance.

Exploring diversity in cryptorhynchine weevils (Coleoptera) using distance-, character- and tree-based species delineation.

Species boundaries are studied in a group of beetles, the western Palaearctic Cryptorhynchinae. We test for congruence of 'traditionally' identified morphospecies with species inferred through parsimony networks, distance-based clustering and the ultrametric tree-based generalized mixed yule-coalescent (GMYC) approach. For that purpose, we sequenced two variable fragments of mitochondrial DNA (CO1 and 16S) for a total of 791 specimens in 217 species of Cryptorhynchinae. Parsimony networks, morphology-calibrated distance clusters and the different tree-based species inferences all achieved low congruence with morphospecies, at best 60%. Although the degree of match with morphospecies was often similar for the different approaches, the composition of clusters partially varied. A barcoding gap was absent in morphospecies-oriented distances as well as for GMYC species clusters. This demonstrates that not only erroneous taxonomic assignments, incomplete lineage sorting, hybridization, or insufficient sampling can compromise distance-based identification, but also differences in speciation rates and uneven tree structure. The initially low match between morphospecies and the different molecular species delineation methods in this case study shows the necessity of combining the output of various methods in an integrative approach. Thereby we obtain an idea about the reliability of the different results and signals, which enables us to fine-tune sampling, delineation technique and data collection, and to identify species that require taxonomic revision.

Surprisingly high genetic divergence of the mitochondrial DNA barcode fragment (COI) within Central European woodlice species (Crustacea, Isopoda, Oniscidea).

DNA barcoding has become the most popular approach for species identification in recent years. As part of the German Barcode of Life project, the first DNA barcode library for terrestrial and freshwater isopods from Germany is presented. The analyzed barcode library included 38 terrestrial (78% of the documented species of Germany) and five freshwater (63%) species. A total of 513 new barcodes was generated and 518 DNA barcodes were analyzed. This analysis revealed surprisingly high intraspecific genetic distances for numerous species, with a maximum of 29.4% for Platyarthrushoffmannseggii Brandt, 1833. The number of BINs per species ranged from one (32 species, 68%) to a maximum of six for Trachelipusrathkii (Brandt, 1833). In spite of such high intraspecific variability, interspecific distances with values between 12.6% and 29.8% allowed a valid species assignment of all analyzed isopods. The observed high intraspecific distances presumably result from phylogeographic events, Wolbachia infections, atypical mitochondrial DNAs, heteroplasmy, or various combinations of these factors. Our study represents the first step in generating an extensive reference library of DNA barcodes for terrestrial and freshwater isopods for future molecular biodiversity assessment studies.

Peering into the Darkness: DNA Barcoding Reveals Surprisingly High Diversity of Unknown Species of Diptera (Insecta) in Germany.

Determining the size of the German insect fauna requires better knowledge of several megadiverse families of Diptera and Hymenoptera that are taxonomically challenging. This study takes the first step in assessing these "dark taxa" families and provides species estimates for four challenging groups of Diptera (Cecidomyiidae, Chironomidae, Phoridae, and Sciaridae). These estimates are based on more than 48,000 DNA barcodes (COI) from Diptera collected by Malaise traps that were deployed in southern Germany. We assessed the fraction of German species belonging to 11 fly families with well-studied taxonomy in these samples. The resultant ratios were then used to estimate the species richness of the four "dark taxa" families (DT families hereafter). Our results suggest a surprisingly high proportion of undetected biodiversity in a supposedly well-investigated country: at least 1800-2200 species await discovery in Germany in these four families. As this estimate is based on collections from one region of Germany, the species count will likely increase with expanded geographic sampling.

Analytical and Numerical Investigation of an Electrochemical Chloride Barrier for Reinforced Concrete Structures.

During the development of a carbon-reinforced mortar interlayer for bridges, the idea of an electrochemical chloride barrier arose. An electrical field is generated between two carbon meshes, and the negatively charged chloride ions are held on the polarized upper carbon mesh to prevent chloride-induced corrosion in the reinforcement. Laboratory tests unexpectedly showed that higher voltages lead to an increase in chloride ions for certain depths of the reference probes. This paper discusses the implementation of analytical and numerical models that finally explain the effect only by the acting diffusion and migration with the help of a finite differences model and finite elements simulations. The effect of the local minimum is limited to positions above the depth of the first carbon layer of the test specimens. It is caused by the lines of the electrical field between the first and second carbon layer. According to the experimental and finite elements simulation results, higher voltages lead to lower chloride concentrations for all positions below the first carbon layer only after sufficient time duration. Therefore, the intended effect of an electrochemical chloride barrier can in general only be observed and confirmed after a certain time depending on position, conditions and parameters.

Investigation into the Integration of Impregnated Glass and Carbon Textiles in a Laboratory Mortar Extruder (LabMorTex).

A promising process for the automatization of concrete structures is extrusion or extrusion molding. An innovative approach is the extrusion of concrete with imbedded technical textiles as reinforcement. For a successful extrusion, the rheological properties of the fresh concrete have to be optimized, as it must be extrudable and have sufficient early strength after leaving the mouthpiece. Within the scope of this paper, a process was developed which allows the integration of flexible as well as stiff impregnated textiles into the extrusion process. For this purpose, different textile-reinforced mortars (TRM) were extruded and their material characteristics were investigated. The results show that the mortar cross-section is considerably strengthened, especially when using carbon textiles, and that extrusion has considerable potential to produce high-performance TRM composites. In uniaxial tension tests with TRM, as well as in the pure roving tensile strength tests, textile stresses of approx. 1200 MPa were achieved for the glass textile and approx. 2250 MPa for the carbon textile. The position of the textile layer deviated a maximal 0.4 mm from its predesigned position, which shows its potential for producing tailor-made TRM elements. In addition, by adjusting the mortar mix design, it was possible to reduce the global warming potential (GWP) of the extrusion compound by up to 49.3% compared to the initial composition from preliminary studies.

Influence of High Temperature Curing and Surface Humidity on the Tensile Strength of UHPC.

The objective of this study is an investigation of the different parameters that influence the tensile strength of ultra-high performance concrete (UHPC). Apart from the shrinkage and stiffness, the tensile strength is an important parameter for the design of crack-free concrete elements, e.g., in machine tool construction. One focus of our work is the influence of concrete curing and the great impact of the mechanical and physical characteristics of hydrated UHPC. For this reason, different curing regimes were investigated. The results show that even after heat treatment or autoclaving, the centric tensile strength of UHPC specimens is strongly influenced by the surrounding ambient humidity. Test specimens that were stored under water after a heat treatment or autoclaving and were still wet during the test had the highest tensile strengths. Storage at 20 °C and 65% relative humidity (rH), however, results in a 25% reduction in tensile strength. Alternating storage between water storage at 20 °C water and storage at 65% rH can also reduce the tensile strength dramatically by up to 70%. In particular, samples that were stored at 65% rH right before testing had very low tensile strengths. Surprisingly, the initially low tensile strength of previously dry stored UHPC can be restored by subsequent water storage. In the absence of any microstructural defects, e.g., microcracks, a possible explanation for this phenomenon can be the stress differences due to a humidity gradient between the core and surfaces and shrinkage combined with a continued reaction of the unhydrated binders of the UHPC.

Electrical Resistivity of Steel Fibre-Reinforced Concrete-Influencing Parameters.

This paper presents a systematic study of the electrical resistivity of different steel fibre-reinforced concretes with fibre contents from 0 kg/m3 to 80 kg/m3 in order to identify possible effects of interactions among concrete composition and fibre type and content regarding electrical resistivity. Based on a literature review, four parameters, w/c ratio, binder content, ground granulated blast-furnace slag (GGBS) and fineness of cement, which show a significant influence on the electrical resistivity of plain concrete, were identified, and their influence on the electrical resistivity as well as interaction effects were investigated. The results of the experiments highlight that the addition of fibres leads to a significant decrease in electrical resistivity, independent of all additional parameters of the concrete composition. Additionally, it was shown that a higher porosity of the concrete, e.g., due to a higher w/c ratio, also results in a lower electrical resistivity. These results are in agreement with the literature review on plain concrete, while the influence of the concrete composition on the electrical resistivity is weaker with the increase in fibre content. The influence of fibre reinforcement is thus not affected by changes in the concrete composition. In general, a higher fibre dosage leads to a decrease in electrical resistivity, but the impact on the electrical resistivity varies slightly with different types of steel fibres. Based on this study, the potential of determining the fibre content using electrical resistivity measurements could be clearly presented.

Relicts from Glacial Times: The Ground Beetle Pterostichus adstrictus Eschscholtz, 1823 (Coleoptera: Carabidae) in the Austrian Alps.

The last ice age considerably influenced distribution patterns of extant species of plants and animals, with some of them now inhabiting disjunct areas in the subarctic/arctic and alpine regions. This arctic-alpine distribution is characteristic for many cold-adapted species with a limited dispersal ability and can be found in many invertebrate taxa, including ground beetles. The ground beetle Pterostichus adstrictus Eschscholtz, 1823 of the subgenus Bothriopterus was previously known to have a holarctic-circumpolar distribution, in Europe reaching its southern borders in Wales and southern Scandinavia. Here, we report the first findings of this species from the Austrian Ötztal Alps, representing also the southernmost edge of its currently known distribution, confirmed by the comparison of morphological characters to other Bothriopterus species and DNA barcoding data. Molecular data revealed a separation of the Austrian and Finish specimens with limited to no gene flow at all. Furthermore, we present the first data on habitat preference and seasonality of P. adstrictus in the Austrian Alps.

The origins of the giant pill-millipedes from Madagascar (Diplopoda: Sphaerotheriida: Arthrosphaeridae).

Giant pill-millipedes (order Sphaerotheriida) are large-bodied millipedes without poison glands which can roll-up into a complete ball. Their disconnected area of distribution spanning South Africa, Madagascar, India, SE Asia, Australia and New Zealand makes them interesting model organisms for biogeographic studies. The here presented phylogeny is based on a molecular dataset covering all areas of distribution with a special focus on Madagascar, where some species of giant pill-millipedes show island gigantism, reaching the size of a baseball. For our study, two mitochondrial genes (partial 16S rRNA and COI) as well as the complete nuclear 18S rDNA were sequenced. While many recent vertebrate studies hint that the ancestors of the recent Malagasy fauna crossed the >350 km wide Mozambique Channel several times, no such crossing was discovered in the Sphaerotheriida. For the first time in a molecular phylogenetic study of soil arthropods, a Madagascar-India group, the family Arthrosphaeridae, is recovered, hinting to a Gondwanan origin of the Sphaerotheriida. The Malagasy-Indian family Arthrosphaeridae forms a monophyletic, statistically well-supported group in all obtained trees. The giant pill-millipedes from Madagascar are paraphyletic because the Malagasy genus Sphaeromimus is the sister-taxon of the Indian Arthrosphaera. In Sphaeromimus, an ecotone shift occurred only once: the spiny forest species Sphaeromimus musicus forms the sister-clade to the species collected in rainforests and littoral rainforests. The two species of the Malagasy genus Zoosphaerium which express island gigantism form a monophyletic group in some trees, but these trees lack good statistical support. Deeper nodes inside the Sphaerotheriida, like the position of the Australian genera Procyliosoma and Epicyliosoma, the Southeast Asian family Zephroniidae and the South African genus Sphaerotherium could not be resolved. This study is the first genetic study inside the order Sphaerotheriida and provides a proper basis for future molecular biogeographic studies in millipedes and soil organisms from Madagascar.

Molecular species identification of Central European ground beetles (Coleoptera: Carabidae) using nuclear rDNA expansion segments and DNA barcodes.

BACKGROUND: The identification of vast numbers of unknown organisms using DNA sequences becomes more and more important in ecological and biodiversity studies. In this context, a fragment of the mitochondrial cytochrome c oxidase I (COI) gene has been proposed as standard DNA barcoding marker for the identification of organisms. Limitations of the COI barcoding approach can arise from its single-locus identification system, the effect of introgression events, incomplete lineage sorting, numts, heteroplasmy and maternal inheritance of intracellular endosymbionts. Consequently, the analysis of a supplementary nuclear marker system could be advantageous. RESULTS: We tested the effectiveness of the COI barcoding region and of three nuclear ribosomal expansion segments in discriminating ground beetles of Central Europe, a diverse and well-studied invertebrate taxon. As nuclear markers we determined the 18S rDNA: V4, 18S rDNA: V7 and 28S rDNA: D3 expansion segments for 344 specimens of 75 species. Seventy-three species (97%) of the analysed species could be accurately identified using COI, while the combined approach of all three nuclear markers provided resolution among 71 (95%) of the studied Carabidae. CONCLUSION: Our results confirm that the analysed nuclear ribosomal expansion segments in combination constitute a valuable and efficient supplement for classical DNA barcoding to avoid potential pitfalls when only mitochondrial data are being used. We also demonstrate the high potential of COI barcodes for the identification of even closely related carabid species.

Contributions to accelerating atmospheric CO2 growth from economic activity, carbon intensity, and efficiency of natural sinks.

The growth rate of atmospheric carbon dioxide (CO(2)), the largest human contributor to human-induced climate change, is increasing rapidly. Three processes contribute to this rapid increase. Two of these processes concern emissions. Recent growth of the world economy combined with an increase in its carbon intensity have led to rapid growth in fossil fuel CO(2) emissions since 2000: comparing the 1990s with 2000-2006, the emissions growth rate increased from 1.3% to 3.3% y(-1). The third process is indicated by increasing evidence (P = 0.89) for a long-term (50-year) increase in the airborne fraction (AF) of CO(2) emissions, implying a decline in the efficiency of CO(2) sinks on land and oceans in absorbing anthropogenic emissions. Since 2000, the contributions of these three factors to the increase in the atmospheric CO(2) growth rate have been approximately 65 +/- 16% from increasing global economic activity, 17 +/- 6% from the increasing carbon intensity of the global economy, and 18 +/- 15% from the increase in AF. An increasing AF is consistent with results of climate-carbon cycle models, but the magnitude of the observed signal appears larger than that estimated by models. All of these changes characterize a carbon cycle that is generating stronger-than-expected and sooner-than-expected climate forcing.

A DNA barcode library for ground beetles of Germany: the genus Pterostichus Bonelli, 1810 and allied taxa (Insecta, Coleoptera, Carabidae).

Species of the ground beetle genus Pterostichus Bonelli, 1810 are some of the most common carabids in Europe. This publication provides a first comprehensive DNA barcode library for this genus and allied taxa including Abax Bonelli, 1810, Molops Bonelli, 1810, Poecilus Bonelli, 1810, and Stomis Clairville, 1806 for Germany and Central Europe in general. DNA barcodes were analyzed from 609 individuals that represent 51 species, including sequences from previous studies as well as more than 198 newly generated sequences. The results showed a 1:1 correspondence between BIN and traditionally recognized species for 44 species (86%), whereas two (4%) species were characterized by two BINs. Three BINs were found for one species (2%), while one BIN for two species was revealed for two species pairs (8%). Low interspecific distances with maximum pairwise K2P values below 2.2% were found for four species pairs. Haplotype sharing was found for two closely related species pairs: Pterostichus adstrictus Eschscholtz, 1823/Pterostichus oblongopunctatus (Fabricius, 1787) and Pterostichus nigrita Paykull, 1790/Pterostichus rhaeticus Heer, 1837. In contrast to this, high intraspecific sequence divergences with values above 2.2% were shown for three species (Molops piceus (Panzer, 1793), Pterostichus panzeri (Panzer, 1805), Pterostichus strenuus (Panzer, 1793)). Summarizing the results, the present DNA barcode library does not only allow the identification of most of the analyzed species, but also provides valuable information for alpha-taxonomy as well as for ecological and evolutionary research. This library represents another step in building a comprehensive DNA barcode library of ground beetles as part of modern biodiversity research.

Multiple origins of deep-sea Asellota (Crustacea: Isopoda) from shallow waters revealed by molecular data.

The Asellota are a highly variable group of Isopoda with many species in freshwater and marine shallow-water environments. However, in the deep sea, they show their most impressive radiation with a broad range of astonishing morphological adaptations and bizarre body forms. Nevertheless, the evolution and phylogeny of the deep-sea Asellota are poorly known because of difficulties in scoring morphological characters. In this study, the molecular phylogeny of the Asellota is evaluated for 15 marine shallow-water species and 101 deep-sea species, using complete 18S and partial 28S rDNA gene sequences. Our molecular data support the monophyly of most deep-sea families and give evidence for a multiple colonization of the deep sea by at least four major lineages of asellote isopods. According to our molecular data, one of these lineages indicates an impressive radiation in the deep sea. Furthermore, the present study rejects the monophyly of the family Janiridae, a group of plesiomorphic shallow-water Asellota, and several shallow-water and deep-sea genera (Acanthaspidia, Ianthopsis, Haploniscus, Echinozone, Eurycope, Munnopsurus and Syneurycope).

A DNA barcode library for ground beetles of Germany: the genus Amara Bonelli, 1810 (Insecta, Coleoptera, Carabidae).

The genus Amara Bonelli, 1810 is a very speciose and taxonomically difficult genus of the Carabidae. The identification of many of the species is accomplished with considerable difficulty, in particular for females and immature stages. In this study the effectiveness of DNA barcoding, the most popular method for molecular species identification, was examined to discriminate various species of this genus from Central Europe. DNA barcodes from 690 individuals and 47 species were analysed, including sequences from previous studies and more than 350 newly generated DNA barcodes. Our analysis revealed unique BINs for 38 species (81%). Interspecific K2P distances below 2.2% were found for three species pairs and one species trio, including haplotype sharing between Amara alpina/Amara torrida and Amara communis/Amara convexior/Amara makolskii. This study represents another step in generating an extensive reference library of DNA barcodes for carabids, highly valuable bioindicators for characterizing disturbances in various habitats.