Thomas Schneider

Prof. Dr. Thomas Schneider


Research Focus & Metrics

Academic Career Length

32Years (1995-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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15 December 2021 in Diversity
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TSThomas Schneider
Thomas Schneider
AVAndy Vierstraete
Andy Vierstraete
OMOle Müller
Ole Müller
GPGert Jan van Pelt
Gert Jan van Pelt
MCMax Caspers
Max Caspers
Henri J. DumontHenri J. Dumont
Henri J. Dumont
Taxonomy of the genus Cordulegaster Leach in Brewster, 1815 in the Eastern part of the Western Palaearctic is poorly resolved. A two-step approach was applied: sequences of mitochondrial and nuclear DNA fragments were used to sort specimens; poorly known or new taxa with their phenotypic variation were described. The existence of two traditional groups (boltonii- and bidentata-group) was confirmed. Cordulegaster coronata Morton, 1916, however, belongs to a different group. Molecular-analysis supported three known and one new species (C. heros Theischinger, 1979, C. picta Selys, 1854, C. vanbrinkae Lohmann, 1993, and C. kalkmani sp. nov.) in the boltonii-group. In the bidentata-group, all specimens from West-Turkey belonged to C. insignis Schneider, 1845, all specimens further east to a complex of four closely related species, which we name charpentieri-complex (C. amasina Morton, 1916, stat. rev., C. mzymtae Bartenev, 1929 C. charpentieri (Kolenati, 1846), stat. rev. and C. cilicia sp. nov.). The following taxa: C. insignis nobilis Morton, 1916, syn. nov., C. nachitschevanica Skvortsov and Snegovaya, 2015, syn. nov. C. plagionyx Skvortsov and Snegovaya, 2015, syn. nov. and the Caucasian subspecies C. insignis lagodechica Bartenev, 1930, syn. nov., were synonymized with C. charpentieri. Finally, we provide a key for all Western Palaearctic Cordulegaster.

23 August 2023 in Diversity
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TSThomas Schneider
Thomas Schneider
AVAndy Vierstraete
Andy Vierstraete
OKOleg O. Kosterin
Oleg O. Kosterin
TSThomas Schneider
Thomas Schneider
FHFang-Shuo Hu
Fang-Shuo Hu
Henri J. DumontHenri J. Dumont
Henri J. Dumont
Aeshnidae Rambur, 1842 are impressive large insects distributed worldwide. Currently, over 500 species are recognized. Nevertheless, the phylogeny of this family is not completely understood. We applied molecular phylogenetic analysis using two popular phylogenetic markers, the mitochondrial COI gene fragment (barcoding sequence) and the nucleic ITS region, containing the ITS1, 5.8S rRNA, and ITS2 sequences. We used available and credible published sequences and 96 newly sequenced specimens. Our analysis involved all West Palaearctic species, all but one genera of the Holarctic Aeshnidae, and most genera worldwide, and is by far the largest molecular study of this family. The topology of all trees created with different algorithms and genes is in favour of the current taxonomic concept, with some remarkable outcomes. Aeshna Fabricius, 1775, was found to be diverged into several branches, especially with respect to the COI gene. Although it appeared not monophyletic in phylogenetic reconstructions based on the ITS region, the analysis of COI and joint analysis suggest its monophyly in the current taxonomical sense, with one notable exception. Aeshna isoceles (Müller, 1767) has fallen out of Aeshna in all analyses, so a new monophyletic genus, Isoaeschna gen. nov. is introduced for it. The genus Brachytron Evans, 1845 tightly clustered with Aeschnophlebia Selys, 1883, Epiaeschna Hagen in Selys, 1883, and Nasiaeschna Selys in Förster, 1900. Thus, we suggest subsuming these four genera under the priority name Brachytron. Tetracanthagyna Selys, 1883 clusters as expected with Brachytron in the ITS tree, but is an independent ancient clade of its own in all COI trees. The genus Polycanthagyna Fraser, 1933 syn. nov. is synonymised to Indaeschna Fraser, 1926. On the species level, we suggest that the American Aeshna septentrionalis Burmeister, 1839 be treated as a subspecies of A. caerulea (Ström, 1783), Aeshna caerulea septentrionalis. We synonymize Gynacantha hyalina Selys, 1882 with Gynacantha subinterrupta Rambur, 1842. Our analysis provides new insights on the tight relationships of the circumboreal species Aeshna juncea and A. subarctica and the intraspecies phylogeny of Aeshna juncea.

12 March 2018 in Zootaxa
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TSThomas Schneider
Thomas Schneider
TSThomas Schneider
Thomas Schneider
OMOle Müller
Ole Müller
Henri J. DumontHenri J. Dumont
Henri J. Dumont
Iran has a complex dragonfly fauna influenced by contacts and overlaps of different geographical zones. Its fauna is dominated by Eurosiberian taxa. However, the SE Province Sistãn-va-Baluchestãn is rich in oriental species, many of which having their western distribution limit in Iran. In NE-Iran, Irano-Turanian elements live and in the S- and SW-Iran African species are found. The Iranian Odonata fauna seems well studied, however, a closer look reveals many uncertainties and confusion, some records coming clearly from misidentification whereas other, which were missing proofs of correct identification remains to be confirmed. Even today, every new collecting trip reveals species new for Iran whereas species new for science are still detected, although rarely. In this checklist we include seven taxa new for Iran: Stylurus ubadschii (although a male of uncertain origin is recorded in Schmidt (1954), Ischnura senegalensis (although two uncertain records were published by Martin (1912) and Schmidt (1954), Coenagrion ponticum, C. lunulatum, C. pulchellum, Lestes macrostigma, and Calopteryx splendens tschaldirica. We critically checked all available data, including all published records. Fourteen taxa have been rejected, or placed in the category for need of confirmation. Till the end of 2017, 100 autochthonous taxa of dragonflies and two migratory species could be confirmed to be or have been present in Iran. We provide distribution maps, created after evaluation of published data and containing our own data from 12 trips to Iran, travelling over 35000 km in the country. Over 200 new localities are integrated. Taxonomic confusion is reduced by rejecting the following taxa for Iran: Calopteryx splendens mingrelica, C. hyalina, Erythromma najas, Aeshna cyanea, Gomphus davidi, and Sympetrum sinaiticum. We regard the taxa Gomphus amseli and G. schneiderii transcaspicus as synonyms of G. schneiderii, and Onychogomphus forcipatus lucidostriatus as a synonym of O. f. albotibialis.

1 November 2014 in Emerging Infectious Diseases
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SBSueleyman Bilal
Sueleyman Bilal
MVMagdalena Sarah Volz
Magdalena Sarah Volz
TFTomas Fiedler
Tomas Fiedler
RPRainer Podschun
Rainer Podschun
TSThomas Schneider
Thomas Schneider

8 April 2022 in Zootaxa
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TSThomas Schneider
Thomas Schneider
AVAndy Vierstraete
Andy Vierstraete
TSThomas Schneider
Thomas Schneider
GPGert Jan VAN Pelt
Gert Jan VAN Pelt
MCMax Caspers
Max Caspers
Henri J. DumontHenri J. Dumont
Henri J. Dumont
Taxonomy of the genus Cordulegaster Leach in Brewster, 1815 in Greece is not completely understood. The taxonomic status of the subspecies C. helladica buchholzi (Lohmann, 1993), C. helladica kastalia (Lohmann, 1993), and C. heros pelionensis Theischinger, 1979 was still unclear. We applied a molecular genetic approach using sequences of mitochondrial and nuclear DNA fragments—cytochrome c oxidase I (COI) and Internal Transcribed Spacer 1 (ITS1). This approach revealed that specimens presently assigned to C. heros pelionensis should be considered as conspecific to the nominate subspecific taxon making C. heros a monotypic species. Two major monophyletic lines were found within the Greek representatives of the species grouped around C. bidentata Selys, 1843: the clade of the European endemic C. bidentata and the clade composed of three species: C. helladica (Lohmann, 1993), C. buchholzi (stat. nov., raised to species level), and C. insignis Schneider, 1845. Cordulegaster helladica is restricted to the Peloponnese. Cordulegaster buchholzi is not restricted to the Cyclades as previously thought, but widespread from the Cyclades over the island Euboea to south-east mainland Greece reaching in the west near Mount Parnassos, where it hybridize with C. bidentata. Hybridization between C. bidentata and C. buchholzi was detected at the Castalian Spring, where in ancient times the Oracle of Delphi was located, and some kilometres east of the Castalian Spring. These hybrids had been formerly named C. helladica kastalia. In the case of C. insignis montandoni St. Quentin, 1971 we have investigated specimens some kilometres away from the type locality in Romania, which all revealed hybrids between C. bidentata and C. insignis. However, we do not know if specimens phenotypically looking like C. insignis from further west in the SE Balkans represent isolated population of C. insignis within the range of C. bidentata or belong to a broader hybrid zone between C. bidentata and C. insignis.

26 September 2024 in Eurosurveillance
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CHCarolin Hackmann
Carolin Hackmann
AGAntonia Genath
Antonia Genath
DGDésirée Gruhl
Désirée Gruhl
AWAnna Weber
Anna Weber
FMFriederike Maechler
Friederike Maechler
RLRasmus Leistner
Rasmus Leistner
Background: Carriage of multidrug-resistant organisms (MDROs) in humans constitutes an important public health concern. Cross-transmission of bacteria between animals and humans has been demonstrated before. Aim: Our aim was to quantify the risk factor ‘pet ownership’ for MDRO colonisation in hospital patients. Methods: We performed a matched case–control study from 2019 to 2022 in Berlin, Germany and compared MDRO-positive and MDRO-negative patients in terms of contact with pets and other risk factors for MDRO acquisition. Patients completed a questionnaire-based interview and provided nasal and rectal swabs. Pet owners provided swab samples from the throat and stool of their pets (dogs and cats). Phenotypically matching samples of owners and pets were analysed via whole genome sequencing. Results: The analyses included 2,891 patients. Reported pet ownership was 17.7% in MDRO-positives (154/871) and 23.4% in MDRO-negatives (472/2,020). Among 397 owner–pet pairs, we identified one pair sharing genotypically indistinguishable pathogens (0.3%). A risk factor analysis of pet ownership was performed for carriers of meticillin-resistant Staphylococcus aureus (MRSA) (OR = 0.662; 95% CI: 0.343–1.277), vancomycin-resistant enterococci (VRE) (OR = 0.764; 95% CI: 0.522–1.118) and multidrug-resistant Gram-negative bacteria (MDR-GNB) (OR = 0.819; 95% CI: 0.620–1.082). Colonisation with MDRO was rare in pets, and dogs were more often colonised than cats (MRSA: 0% vs 0%, VRE: 1.5% vs 1.0%, MDR-GNB: 17.2% vs 3.6%). Conclusion: Transmission of MDROs between humans and pets is possible though rare. In an urban living space, neither cat nor dog ownership appears as a relevant risk factor for MDRO carriage in hospital patients.