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1.
Ned Tijdschr Geneeskd ; 1672023 11 15.
Article in Dutch | MEDLINE | ID: mdl-37994711

ABSTRACT

In the past years several developments have occurred in the care for patients with pancreatic cancer in the Netherlands. New palliative chemotherapy strategies using FOLFRINOX or gemcitabine/nab-paclitaxel were introduced for patients with advanced disease. Due to centralization of pancreatic surgery, introduction of neoadjuvant therapy, and the implementation of standardized postoperative care more patients became enable for resection, postoperative mortality decreased, and survival improved. Within the randomized PREOPANC trial of the Dutch Pancreatic Cancer Group (DPCG), neoadjuvant therapy using chemoradiation for (borderline) resectable pancreatic cancer improved five-year survival from 7% to 21%. Furthermore, due to nationwide training programs, the use of minimally invasive surgery has increased. Regardless of these developments, the survival of patients with pancreatic cancer is still low and 61% of Dutch patients with pancreatic cancer patients do not receive any tumor targeted therapy. The DPCG is active to improve quality of care through auditing, research, guideline development, and education.


Subject(s)
Gemcitabine , Pancreatic Neoplasms , Humans , Deoxycytidine/therapeutic use , Netherlands , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Pancreatic Neoplasms/pathology
2.
Ecol Evol ; 13(11): e10785, 2023 Nov.
Article in English | MEDLINE | ID: mdl-38034337

ABSTRACT

The factors that influence population structure and connectivity are unknown for most terrestrial invertebrates but are of particular interest both for understanding the impacts of disturbance and for determining accurate levels of biodiversity and local endemism. The main objective of this study was to determine the historical patterns of genetic differentiation and contemporary gene flow in the terrestrial snail, Austrochloritis kosciuszkoensis (Shea & O. L. Griffiths, 2010). Snails were collected in the Mt Buffalo and Alpine National Parks in Victoria, in a bid to understand how populations of this species are connected both within continuous habitat and between adjacent, yet separate environments. Utilising both mitochondrial DNA (mtDNA) and single nucleotide polymorphism (SNP) data, the degree of population structure was determined within and between sites. Very high levels of genetic divergence were found between the Mt Buffalo and Alpine snails, with no evidence for genetic exchange detected between the two regions, indicating speciation has possibly occurred between the two regions. Our analyses of the combined mtDNA and nDNA (generated from SNPs) data have revealed patterns of genetic diversity that are consistent with a history of long-term isolation and limited connectivity. This history may be related to past cycles of changes to the climate over hundreds of thousands of years, which have, in part, caused the fragmentation of Australian forests. Within both regions, extremely limited gene flow between separate populations suggests that these land snails have very limited dispersal capabilities across existing landscape barriers, especially at Mt Buffalo: here, populations only 5 km apart from each other are genetically differentiated. The distinct genetic divergences and clearly reduced dispersal ability detected in this data explain the likely existence of at least two previously unnamed cryptic Austrochloritis species within a 30-50 km radius, and highlight the need for more concentrated efforts to understand population structure and gene flow in terrestrial invertebrates.

3.
PLoS One ; 18(7): e0288533, 2023.
Article in English | MEDLINE | ID: mdl-37494326

ABSTRACT

The superfamily Orthalicoidea comprises approximately 2,000 species of terrestrial gastropods, mostly concentrated in the Neotropics but also present in southern Africa and Oceania. We provide a multi-marker molecular phylogeny of this superfamily, reassessing its family- and genus-level classification. We exclude two families from the group, Odontostomidae and Vidaliellidae, transferring them to Rhytidoidea based on their phylogenetic relationships as recovered herein. Two new families are recognized herein as members of Orthalicoidea, Tomogeridae and Cyclodontinidae fam. nov. The family Megaspiridae and the subfamily Prestonellinae are paraphyletic but are retained herein for taxonomic stability. The subfamily Placostylinae is synonymized with Bothriembryontinae. The new genera Alterorhinus gen. nov. and Sanniostracus gen. nov. containing some Brazilian species are described here to better reflect the phylogeny. The fossil record and paleobiogeographic history of the group is explored under the new phylogenetic framework.


Subject(s)
Snails , Humans , Animals , Phylogeny , Snails/genetics , Africa, Southern , Brazil
4.
Ecol Evol ; 12(12): e9650, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36568864

ABSTRACT

DNA barcoding has been used worldwide to identify biological specimens and to delimit species. It represents a cost-effective, fast, and efficient way to assess biodiversity with help of the public Barcode of Life Database (BOLD) accounting for more than 236,000 animal species and more than 10 million barcode sequences. Here, we performed a meta-analysis of available barcode data of central European Coleoptera to detect intraspecific genetic patterns among ecological groups in relation to geographic distance with the aim to investigate a possible link between infraspecific variation and species ecology. We collected information regarding feeding style, body size, as well as habitat and biotope preferences. Mantel tests and two variants of Procrustes analysis, both involving the Principal Coordinates Neighborhood Matrices (PCNM) approach, were applied on genetic and geographic distance matrices. However, significance levels were too low to further use the outcome for further trait investigation: these were in mean for all ecological guilds only 7.5, 9.4, or 15.6% for PCNM + PCA, NMDS + PCA, and Mantel test, respectively, or at best 28% for a single guild. Our study confirmed that certain ecological traits were associated with higher species diversity and foster stronger genetic differentiation. Results suggest that increased numbers of species, sampling localities, and specimens for a chosen area of interest may give new insights to explore barcode data and species ecology for the scope of conservation on a larger scale. We performed a meta-analysis of available barcode data of central European beetles to detect intraspecific genetic patterns among ecological groups in relation to geographic distance, regarding feeding style, body size, as well as habitat and biotope preferences. Our study confirmed that certain ecological traits were associated with higher species diversity and foster stronger genetic differentiation. However, significance levels were too low to further use the outcome for further trait investigation.

5.
PeerJ ; 10: e13139, 2022.
Article in English | MEDLINE | ID: mdl-35757168

ABSTRACT

We introduce a new method of estimating accepted species diversity by adapting mark-recapture methods to comparisons of taxonomic databases. A taxonomic database should become more complete over time, so the error bar on an estimate of its completeness and the known diversity of the taxon it treats will decrease. Independent databases can be correlated, so we use the time course of estimates comparing them to understand the effect of correlation. If a later estimate is significantly larger than an earlier one, the databases are positively correlated, if it is significantly smaller, they are negatively correlated, and if the estimate remains roughly constant, then the correlations have averaged out. We tested this method by estimating how complete MolluscaBase is for accepted names of terrestrial gastropods. Using random samples of names from an independent database, we determined whether each name led to a name accepted in MolluscaBase. A sample tested in August 2020 found that 16.7% of tested names were missing; one in July 2021 found 5.3% missing. MolluscaBase grew by almost 3,000 accepted species during this period, reaching 27,050 species. The estimates ranged from 28,409 ± 365 in 2021 to 29,063 ± 771 in 2020. All estimates had overlapping 95% confidence intervals, indicating that correlations between the databases did not cause significant problems. Uncertainty beyond sampling error added 475 ± 430 species, so our estimate for accepted terrestrial gastropods species at the end of 2021 is 28,895 ± 630 species. This estimate is more than 4,000 species higher than previous ones. The estimate does not account for ongoing flux of species into and out of synonymy, new discoveries, or changing taxonomic methods and concepts. The species naming curve for terrestrial gastropods is still far from reaching an asymptote, and combined with the additional uncertainties, this means that predicting how many more species might ultimately be recognized is presently not feasible. Our methods can be applied to estimate the total number of names of Recent mollusks (as opposed to names currently accepted), the known diversity of fossil mollusks, and known diversity in other phyla.


Subject(s)
Gastropoda , Animals , Mollusca , Fossils , Databases, Factual , Research Design
6.
Ecol Evol ; 11(9): 4366-4378, 2021 May.
Article in English | MEDLINE | ID: mdl-33976816

ABSTRACT

Mountain regions are centers of biodiversity endemism at a global scale but the role of arid-zone mountain ranges in shaping biodiversity patterns is poorly understood. Focusing on three guilds of taxa from a desert upland refugium in Australia, we sought to determine: (a) the relative extent to which climate, terrain or geological substrate predict endemism, and (b) whether patterns of endemism are complimentary across broad taxonomic guilds. We mapped regional endemism for plants, land snails, and vertebrates using combined Species Distribution Models (SDMs) for all endemic taxa (n = 82). We then modelled predictors of endemism using Generalised Additive Models (GAMs) and geology, terrain, and climate variables. We tested for the presence of inter- and intraguild hotspots of endemism. Many individual plant and land snail taxa were tightly linked with geology, corresponding to small distributions. Conversely, most vertebrate taxa were not constrained to specific geological substrates and occurred over larger areas. However, across all three guilds climate was the strongest predictor of regional endemism, particularly for plants wherein discrete hotspots of endemism were buffered from extreme summer temperatures. Land snail and vertebrate endemism peaked in areas with highest precipitation in the driest times of the year. Hotspots of endemism within each guild poorly predicted endemism in other guilds. We found an overarching signal that climatic gradients play a dominant role in the persistence of endemic taxa in an arid-zone mountain range system. An association with higher rainfall and cooler temperatures indicates that continuing trends toward hotter and drier climates may lead to range contractions in this, and potentially other, arid-zone mountain biotas. Contrasting patterns of endemism across guilds highlight the need to couple comprehensive regional planning for the protection of climate refugia, with targeted management of more localized and habitat specialist taxa.

7.
Inorg Chem ; 59(13): 9294-9307, 2020 Jul 06.
Article in English | MEDLINE | ID: mdl-32558559

ABSTRACT

The paramagnetic pyrazolylborates Tp2M and Tp*2M (M = Cu, Ni, Co, Fe, Mn, Cr, V) as well as [Tp2M]+ and [Tp*2M]+ (M = Fe, Cr, V) have been synthesized and their NMR spectra recorded. The 1H signal shift ranges vary from ∼30 ppm (Cu(II) and V(III)) to ∼220 ppm (Co(II)), and the 13C signal shift ranges from ∼180 ppm (Fe(III)) to ∼1150 ppm (Cr(II)). The 11B and 14N shifts are ∼360 and ∼730 ppm, respectively. Both negative and positive shifts have been observed for all nuclei. The narrow NMR signals of the Co(II), Fe(II), Fe(III), and V(III) derivatives provide resolved 13C,1H couplings. All chemical shifts have been calculated from first-principles on a modern version of Kurland-McGarvey theory which includes optimized structures, zero-field splitting, and g tensors, as well as signal shift contributions. Temperature dependence in the Fe(II) spin-crossover complex results from the equilibrium of the ground singlet and the excited quintet. We illustrate both the assignment and analysis capabilities, as well as the shortcomings of the current computational methodology.

8.
Syst Biol ; 69(5): 944-961, 2020 09 01.
Article in English | MEDLINE | ID: mdl-32061133

ABSTRACT

The Viviparidae, commonly known as River Snails, is a dominant group of freshwater snails with a nearly worldwide distribution that reaches its highest taxonomic and morphological diversity in Southeast Asia. The rich fossil record is indicative of a probable Middle Jurassic origin on the Laurasian supercontinent where the group started to diversify during the Cretaceous. However, it remains uncertain when and how the biodiversity hotspot in Southeast Asia was formed. Here, we used a comprehensive genetic data set containing both mitochondrial and nuclear markers and comprising species representing 24 out of 28 genera from throughout the range of the family. To reconstruct the spatiotemporal evolution of viviparids on a global scale, we reconstructed a fossil-calibrated phylogeny. We further assessed the roles of cladogenetic and anagenetic events in range evolution. Finally, we reconstructed the evolution of shell features by estimating ancestral character states to assess whether the appearance of sculptured shell morphologies was driven by major habitat shifts. The molecular phylogeny supports the monophyly of the three subfamilies, the Bellamyinae, Lioplacinae, and Viviparinae, but challenges the currently accepted genus-level classification in several cases. The almost global distribution of River Snails has been influenced both by comparatively ancient vicariance and more recent founder events. In Southeast Asia, Miocene dispersal was a main factor in shaping the modern species distributions. A recurrent theme across different viviparid taxa is that many species living in lentic waters exhibit sculptured shells, whereas only one strongly sculptured species is known from lotic environments. We show that such shell sculpture is habitat-dependent and indeed evolved several times independently in lentic River Snails. Considerably high transition rates between shell types in lentic habitats probably caused the co-occurrence of morphologically distinct shell types in several lakes. In contrast, directional evolution toward smooth shells in lotic habitats, as identified in the present analyses, explains why sculptured shells are rarely found in these habitats. However, the specific factors that promoted changes in shell morphology require further work. [biogeographical analyses; fossil-calibrated phylogeny; fossil-constrained analyses; Southeast Asia; stochastic character mapping.].


Subject(s)
Animal Distribution , Biodiversity , Ecosystem , Snails/anatomy & histology , Snails/classification , Animal Shells/anatomy & histology , Animals , Biological Evolution
9.
Chemistry ; 25(52): 12120-12136, 2019 Sep 18.
Article in English | MEDLINE | ID: mdl-31461188

ABSTRACT

The local magnetic structure in the [FeIII (Tp)(CN)3 ]- building block was investigated by combining paramagnetic Nuclear Magnetic Resonance (pNMR) spectroscopy and polarized neutron diffraction (PND) with first-principle calculations. The use of the pNMR and PND experimental techniques revealed the extension of spin-density from the metal to the ligands, as well as the different spin mechanisms that take place in the cyanido ligands: Spin-polarization on the carbon atoms and spin-delocalization on the nitrogen atoms. The results of our combined density functional theory (DFT) and multireference calculations were found in good agreement with the PND results and the experimental NMR chemical shifts. Moreover, the ab-initio calculations allowed us to connect the experimental spin-density map characterized by PND and the suggested distribution of the spin-density on the ligands observed by NMR spectroscopy. Interestingly, significant differences were observed between the pseudo-contact contributions of the chemical shifts obtained by theoretical calculations and the values derived from NMR spectroscopy using a simple point-dipole model. These discrepancies underline the limitation of the point-dipole model and the need for more elaborate approaches to break down the experimental pNMR chemical shifts into contact and pseudo-contact contributions.

10.
Int J Biol Macromol ; 133: 522-528, 2019 Jul 15.
Article in English | MEDLINE | ID: mdl-31009691

ABSTRACT

Herein, we described the complete mitochondrial genome ('mitogenome') of the Chinese land snail Cyclophorus martensianus, which is the first published mitogenome for the caenogastropod family Cyclophoridae. This mitogenome is 15,308 bp long consisting of 37 genes: 13 protein-coding genes (PCGs), 22 tRNA genes and two rRNA genes. The A + T content (69.6%) is distinctly higher than the GC content (30.4%). Most PCGs start with ATN as initiation codons, and all PCGs have the conventional stop codons TAA and TAG. Overall, the biochemical properties and gene order of the cyclophorid mitogenome are very similar to those of other documented caenogastropod mitogenomes. We corroborate the findings of earlier studies that mitochondrial gene order is rather conserved among caenogastropods. Caenogastropoda are the taxonomically, morpho-anatomically and ecologically most diverse group of living gastropods comprising lineages inhabiting marine, freshwater, and terrestrial environments. Traditionally, the three most speciose groups of non-marine caenogastropods have all been placed in a single group, the Architaenioglossa. This group contains two freshwater lineages, the Viviparoidea and Ampullaroidea, and the terrestrial Cyclophoroidea. However, architaenioglossan relationships have remained controversial with several morphology-based on molecular phylogenetic analyses supporting contradicting phylogenetic hypotheses. In order to more robustly resolve the relationships among the Architaenioglossa, we have performed phylogenetic analyses of caenogastropod mitogenomes including the new mitogenome of Cyclophorus martensianus. Our phylogenetic reconstructions are based on the amino acid sequences of all protein-coding genes and consistently recovered Architaenioglossa as non-monophyletic.


Subject(s)
Genome, Mitochondrial/genetics , Phylogeny , Snails/genetics , Animals , Base Sequence , Evolution, Molecular , Gene Order/genetics , RNA, Ribosomal/genetics , RNA, Transfer/genetics , Sequence Analysis
11.
Mol Phylogenet Evol ; 135: 177-184, 2019 06.
Article in English | MEDLINE | ID: mdl-30858078

ABSTRACT

Stylommatophora is a main clade of Gastropoda that encompasses approximately 112 gastropod families and may exceed a total of 30,000 species. Twenty-four complete stylommatophoran mitogenomes have been sequenced to date, yet our understanding of mitochondrial evolution in stylommatophorans is still in its infancy. To further expand the set of available mitogenomes, we sequenced the mitogenome of Meghimatium bilineatum (Arionoidea: Philomycidae), a widespread land slug in East Asia. This is the first report on a mitogenome of the superfamily Arionoidea, and indeed on a terrestrial slug. The mitogenome of Meghimatium bilineatum comprises 13,972 bp and exhibits a novel, highly distinctive gene arrangement among the Stylommatophora. Phylogenetic reconstructions based on the sequences of all protein-coding genes consistently recovered Meghimatium bilineatum as sister-group of the Succineidae. A phylogenetic reconstruction based on gene order, however, suggested a highly divergent tree topology, which is less credible when taking into account prior knowledge of stylommatophoran relationships. Our CREx (Common interval Rearrangement Explorer) analysis suggested that three successive events of tandem duplication random loss (TDRL) best explain the evolutionary process of gene order rearrangement in Meghimatium bilineatum from an ancestral stylommatophoran mitogenome. The present example offers new insights into the mechanisms of mitogenome rearrangements in gastropods at large and into the usefulness of mitogenomic gene order as a phylogenetic marker.


Subject(s)
Gastropoda/genetics , Gene Rearrangement , Genome, Mitochondrial , Animals , Base Sequence , Chromosome Mapping , Asia, Eastern , Gene Order , Mitochondria/genetics , Phylogeny
12.
Mol Ecol Resour ; 16(5): 1107-23, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27289081

ABSTRACT

The qualification of orthology is a significant challenge when developing large, multiloci phylogenetic data sets from assembled transcripts. Transcriptome assemblies have various attributes, such as fragmentation, frameshifts and mis-indexing, which pose problems to automated methods of orthology assessment. Here, we identify a set of orthologous single-copy genes from transcriptome assemblies for the land snails and slugs (Eupulmonata) using a thorough approach to orthology determination involving manual alignment curation, gene tree assessment and sequencing from genomic DNA. We qualified the orthology of 500 nuclear, protein-coding genes from the transcriptome assemblies of 21 eupulmonate species to produce the most complete phylogenetic data matrix for a major molluscan lineage to date, both in terms of taxon and character completeness. Exon capture targeting 490 of the 500 genes (those with at least one exon >120 bp) from 22 species of Australian Camaenidae successfully captured sequences of 2825 exons (representing all targeted genes), with only a 3.7% reduction in the data matrix due to the presence of putative paralogs or pseudogenes. The automated pipeline Agalma retrieved the majority of the manually qualified 500 single-copy gene set and identified a further 375 putative single-copy genes, although it failed to account for fragmented transcripts resulting in lower data matrix completeness when considering the original 500 genes. This could potentially explain the minor inconsistencies we observed in the supported topologies for the 21 eupulmonate species between the manually curated and 'Agalma-equivalent' data set (sharing 458 genes). Overall, our study confirms the utility of the 500 gene set to resolve phylogenetic relationships at a range of evolutionary depths and highlights the importance of addressing fragmentation at the homolog alignment stage for probe design.


Subject(s)
DNA/isolation & purification , Exons , Gastropoda/classification , Gastropoda/genetics , Genotyping Techniques/methods , Nucleic Acid Hybridization/methods , Specimen Handling/methods , Animals , DNA/chemistry , DNA/genetics , Evolution, Molecular , High-Throughput Nucleotide Sequencing , Oligonucleotide Probes/genetics , Phylogeny , Polymerase Chain Reaction , Transcriptome
13.
Mol Phylogenet Evol ; 94(Pt A): 101-12, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26335041

ABSTRACT

Progressive aridification since the mid-Miocene has had a significant influence on the evolution of the biota in the arid zone of central Australia. Especially moisture sensitive groups, such as snails, are often restricted to topographically complex areas, which have acted as refugia in an otherwise inhospitable environment. This historical fragmentation is deemed to be a potent agent of allopatric lineage diversification. Camaenid land snails are amongst only a few terrestrial gastropods that have managed to survive in the arid zone probably due to their ability to escape desiccation through aestivation. Here, we present the first study of the mitochondrial lineage differentiation in an endemic land snail genus from the Australian 'Red Centre', Granulomelon Iredale, 1933. Exposing significant incongruence between mtDNA phylogeny and morphology-based taxonomy, we completely revise the species and genus level taxonomy of this camaenid group. We demonstrate that this genus contains three species, G. grandituberculatum, G. adcockianum and G. squamulosum, which have so far been assigned to different genera: Granulomelon Iredale, 1933 (junior synonym: Baccalena Iredale, 1937), Basedowena Iredale, 1937 and Pleuroxia Ancey, 1887. Two of these species are widespread comprising multiple divergent mitochondrial lineages. Based on a molecular clock estimate, these lineages diverged approximately during the mid-Pleistocene, a period of particularly severe aridification. The phylogeographic patterns are consistent with an isolation-by-distance model in one species but not the other. We suggest that these differences can be attributed to their distinctive aestivation behavior.


Subject(s)
Desert Climate , Estivation/physiology , Phylogeny , Snails/classification , Snails/physiology , Animals , Australia , Biological Evolution , DNA, Mitochondrial/genetics , Male , Mitochondria/genetics , Phylogeography , Snails/genetics
14.
Inorg Chem ; 54(14): 6801-6, 2015 Jul 20.
Article in English | MEDLINE | ID: mdl-26134712

ABSTRACT

The (133)Cs magic-angle spinning NMR spectra of the paramagnetic compounds CsM(II)[M(III)(CN)6], M(II) = Ni, Co, Fe, Mn; M(II) = Co, Fe, yield unusually large and temperature-dependent signal shifts (up to -950 ppm relative to CsCl at 298 K). Comparison with the spectra of the diamagnetic analogues CsM[Co(CN)6], M = Zn, Cd, shows that the shifts are largely due to the unpaired electrons. This is ascribed to through-bond transfer of spin to the Cs(+) ions, while the through-space effect of the magnetic moments on the signal shifts is shown to be virtually negligible. The mechanism inducing negative spin at Cs(+) is discussed. The magnitude of the spin density (average: |5.8 × 10(-3)| (a.u.) (-3)) suggests that Cs(+) is involved in magnetic exchange interactions of corresponding Prussian blue derivatives.

15.
Sci Data ; 2: 150013, 2015.
Article in English | MEDLINE | ID: mdl-25977817

ABSTRACT

Analyses of species traits have increased our understanding of how environmental drivers such as disturbances affect the composition of arthropod communities and related processes. There are, however, few studies on which traits in the arthropod community are affected by environmental changes and which traits affect ecosystem functioning. The assembly of arthropod traits of several taxa is difficult because of the large number of species, limited availability of trait databases and differences in available traits. We sampled arthropod species data from a total of 150 managed grassland plots in three regions of Germany. These plots represent the spectrum from extensively used pastures to mown pastures to intensively managed and fertilized meadows. In this paper, we summarize information on body size, dispersal ability, feeding guild and specialization (within herbivores), feeding mode, feeding tissue (within herbivorous suckers), plant part (within herbivorous chewers), endophagous lifestyle (within herbivores), and vertical stratum use for 1,230 species of Coleoptera, Hemiptera (Heteroptera, Auchenorrhyncha), Orthoptera (Saltatoria: Ensifera, Caelifera), and Araneae, sampled by sweep-netting between 2008 and 2012. We compiled traits from various literature sources and complemented data from reliable internet sources and the authors' experience.


Subject(s)
Coleoptera , Hemiptera , Orthoptera , Spiders , Animals , Coleoptera/anatomy & histology , Coleoptera/physiology , Ecosystem , Feeding Behavior , Germany , Grassland , Hemiptera/anatomy & histology , Hemiptera/physiology , Orthoptera/anatomy & histology , Orthoptera/physiology , Spiders/anatomy & histology , Spiders/physiology
16.
Mol Ecol Resour ; 15(4): 795-818, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25469559

ABSTRACT

Beetles are the most diverse group of animals and are crucial for ecosystem functioning. In many countries, they are well established for environmental impact assessment, but even in the well-studied Central European fauna, species identification can be very difficult. A comprehensive and taxonomically well-curated DNA barcode library could remedy this deficit and could also link hundreds of years of traditional knowledge with next generation sequencing technology. However, such a beetle library is missing to date. This study provides the globally largest DNA barcode reference library for Coleoptera for 15 948 individuals belonging to 3514 well-identified species (53% of the German fauna) with representatives from 97 of 103 families (94%). This study is the first comprehensive regional test of the efficiency of DNA barcoding for beetles with a focus on Germany. Sequences ≥500 bp were recovered from 63% of the specimens analysed (15 948 of 25 294) with short sequences from another 997 specimens. Whereas most specimens (92.2%) could be unambiguously assigned to a single known species by sequence diversity at CO1, 1089 specimens (6.8%) were assigned to more than one Barcode Index Number (BIN), creating 395 BINs which need further study to ascertain if they represent cryptic species, mitochondrial introgression, or simply regional variation in widespread species. We found 409 specimens (2.6%) that shared a BIN assignment with another species, most involving a pair of closely allied species as 43 BINs were involved. Most of these taxa were separated by barcodes although sequence divergences were low. Only 155 specimens (0.97%) show identical or overlapping clusters.


Subject(s)
Coleoptera/classification , Coleoptera/genetics , DNA Barcoding, Taxonomic , Databases, Nucleic Acid , Animals , DNA, Mitochondrial/chemistry , DNA, Mitochondrial/genetics , Germany , Molecular Sequence Data , Sequence Analysis, DNA
17.
Mol Phylogenet Evol ; 83: 44-55, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25463754

ABSTRACT

North-western Australia harbours more than 300 species of camaenid land snail in 41 genera exhibiting considerable and well documented morphological diversity. We performed Bayesian and Maximum Likelihood analyses of concatenated nuclear (28S) and mitochondrial (COI, 16S) DNA sequences from 140 species of 37 of these genera plus an additional 27 extralimital species in order to resolve their phylogenetic relationships and to address the significance of morphological characters for the delineation of monophyletic taxa. While north-western Australian Camaenidae in their entirety are not monophyletic with respect to extralimital groups, they underwent extensive in situ-diversification in several independent phylogenetic radiations. A Maximum Likelihood-based character history reconstruction revealed extensive convergence in all studied shell characters and in three out of four genital features across this group. However, in some genera close morphological similarity is best explained by the retention of ancestral characters. We hypothesize that both morphological stasis in some groups and convergent character evolution in others can to a large extent be attributed to adaptive transformations in response to historically increasing aridity throughout north-western Australia in concert with structural constraints.


Subject(s)
Biological Evolution , Phylogeny , Snails/classification , Animal Shells/anatomy & histology , Animals , Australia , Bayes Theorem , Genitalia/anatomy & histology , Likelihood Functions , Models, Genetic , Sequence Analysis, DNA , Snails/anatomy & histology , Snails/genetics
18.
Inorg Chem ; 52(21): 12634-44, 2013 Nov 04.
Article in English | MEDLINE | ID: mdl-24147815

ABSTRACT

With the aim of probing the spin density distribution in the open-shell cyanometallates Cs2K[M(CN)6] (M = Cr, Mn, Fe), K3[M(CN)6] (M = Mn, Fe), K4[M(CN)6] (M = Cr, Mn), and K4[V(CN)7] have been studied by solid-state (13)C and (15)N NMR spectroscopy. The signals appear in strongly shifted and broad ranges ((13)C, -2100 to -8900 ppm; (15)N, -1900 to 2400 ppm) except K4[V(CN)7], which is NMR-silent. Analysis of the isotropic signal shifts yields negative spin density in all carbon 2s orbitals (up to 12.2% at the six ligands of [Mn(CN)6](3-)) and positive spin density in all nitrogen 2s orbitals (up to 1.1% at the six ligands of [Mn(CN)6](4-) and [Fe(CN)6](3-)). This is in accord with the induction of alternating spin at the CN ligands by successive polarization of σ bonds triggered by the spin center M(n+). The signal shift anisotropies are related to spin in the carbon and nitrogen 2pπ and 2pσ orbitals. In the case of Cs2K[Cr(CN)6] and K4[Cr(CN)6] much positive spin is found in the nitrogen 2pπ orbitals, which corresponds to direct M → N spin transfer. On Cs2K[M(CN)6] (M = Mn, Fe), the 2pπ spin density at nitrogen is negative. The results are in accord with and extend the data of polarized neutron diffraction and EPR spectroscopy. Owing to high signal resolution, small deviations of the [M(CN)6](n-) ions from octahedral symmetry and disorder of crystal layers have been detected. This corresponds to the crystal symmetry and to Jahn-Teller distortion. The disorder entails a scatter of spin densities. In the case of K4[Mn(CN)6] it reaches 19% for the C 2s orbitals and 80% for the N 2s orbitals with regard to the respective smallest spin population.

19.
Zookeys ; (261): 15-39, 2013.
Article in English | MEDLINE | ID: mdl-23653507

ABSTRACT

Six species of Gastrocopta have been identified from the Pilbara region, Western Australia, by means of comparative analyses of shell and mtDNA variation. Three of these species, Gastrocopta hedleyi, Gastrocopta larapinta and Gastrocopta servilis, have been recorded in the Pilbara for the first time. Gastrocopta sp. CW1 is probably new to science and might be endemic to the region. By contrast, Gastrocopta hedleyi, Gastrocopta larapinta and Gastrocopta mussoni are shown to be widespread.

20.
Zootaxa ; 3608: 101-15, 2013 Jan 17.
Article in English | MEDLINE | ID: mdl-24614453

ABSTRACT

The Western Australian Kimberley region harbours a diverse fauna of camaenid land snails characterised by marked patterns of narrow range endemism. The recently described genus Australocosmica comprised three species that are endemic to single offshore islands or island groups. Material of a further seven candidate species recognised by the late Alan Solem has been examined. Six of these manuscript species, NSP 40 (= A. rotunda n. sp.), NSP 76 (= A. pallida n. sp.), NSP 77 (= A. buffonensis n. sp.), NSP 78 (= A. bernoulliensis n. sp.), NSP 79 (= A. crassicostata n. sp.), and NSP 80 (= A. nana n. sp.), are here newly described based on examination of shell morphology and penial anatomy. Based on our findings, we are presenting an updated generic diagnosis of Australocosmica. Statistical analyses revealed that species exhibit similar shell characters (colouration, sculpture, dimensions), which render the delimitation of species based only on shells difficult. However, species were found to differ significantly in their penial anatomy. Although the material studied was not suitable for DNA extraction, the anatomical differences were considered sufficient to permit the description of distinct species.


Subject(s)
Snails/anatomy & histology , Snails/classification , Animals , Female , Male , Western Australia
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