Although formerly common and widely distributed most of the unionid species are nowadays among the losers of anthropogenic changes of our environment. In Germany as well as in Baden-Württemberg the Thick river mussel (Unio crassus) – formerly the most common species with an impressively broad ecological spectrum – is currently threatened by extinction. Data on the current distribution of the different species and also on the genetic structure of the surviving populations is limited.
Despite various assessments specifically for the Thick river mussel, data on its distribution as well as on other unionid species are scattered and incomplete. In addition to a compilation of the existing records the project included localized mapping efforts across the area of the county.
For several species (e. g. Unio pictorum, U. crassus, Pseudanodonta complanata) it has long been discussed in literature to have subspecies or local races ("Danube-race", "Rhine-race") based on differences in shell morphology. Some authors interpret the distribution patterns of these forms even as hint to ancient connections of the drainage systems. For south-western Germany these considerations are so far entirely based on shell morphology. To approach these questions the project comprised a first pilot study exemplarily for the Thick river mussel applying population genetic methods (establishment of methods and assessment of results for selected populations).
The project was supported by the funds of the Fischereiabgabe and managed by the Regierungspräsidium Stuttgart.
With Dr. Ira Richling (project leader) and Cornelia Krause.
Biogeography of the laurel forest species of Gesnouinia, Visnea and Geranium
For my PhD thesis, I analyze the temporal and spatial origin of the laurel forest species of Gesnouinia, Visnea and Geranium. To this end, I create molecular dated phylogenies, which serve as basis for biogeographic reconstructions. In case of Visnea, fossils are available and may provide additional information regarding distribution and age. To test the correct assignment of the fossils, MCT Scans of recent Visnea fruits are compared with MCT-Scans of fossil Visnea fruits.
Nested in a tribe of herbaceous species, Gesnouinia likely is an example for an insular woody laurel forest species. To test for this hypothesis, I analyze its stem anatomy performing micromtome sections.
Schüßler C., Bräuchler C., Reyes‐Betancort J. A., Koch M. A., & Thiv M. (2019). Island biogeography of the Macaronesian Gesnouinia and Mediterranean Soleirolia (Parietarieae, Urticaceae) with implications for the evolution of insular woodiness. Taxon, 68(3), 537-556.
Schüßler C., Thiv M., Wörz A. 2018. Indigenous and synanthropic populations of Galanthusnivalis L. in Baden-Württemberg. Integrative Systematics 1, 7-15.
Schüßler C., Freitag H., Koteyeva N., Schmidt D., Edwards G., Voznesenskaya E., Kadereit G. 2016. Molecular phylogeny and forms of photosynthesis in tribe Salsoleae (Chenopodiaceae). Journal of Experimental Botany 68, 207-223.
Kondraskov P., Schütz N., Schüßler C., Menezes de Sequeira M., Santos Guerra A., Caujapé-Castells J., Jaén-Molina R., Marrero-Rodríguez A., Koch M.A., Linder P., Kovar-Eder J., Thiv M. 2015. Biogeography of Mediterranean Hotspot Biodiversity: Re-Evaluating the 'Tertiary Relict' Hypothesis of Macaronesian Laurel Forests. PLoS ONE 10(7): e0132091. doi:10.1371/journal.pone.0132091.
Schüßler, C., Bräuchler, C., Reyes-Betancort, J.A., Koch, M.A., Thiv, M. (2018): Canarian Gesnouinia (Urticaceae): Is secondary woodiness consistent with the Tertiary relict hypothesis?. FloraMac 2018, Madeira.
Schüßler, C., Bräuchler, C., Koch, M.A., Thiv, M. (2016): Evolution of woodiness in Canarian genus Gesnouinia (Urticaceae). 23rd International Symposium on ‘Biodiversity and Evolutionary Biology’ of the German Botanical Society 2016, München.
Kondraskov, P., Schüßler, C., Schütz, N., Thiv, M. (2015): Are Macaronesian laurel forests 'Tertiary' relicts? 24th International Workshop on Plant Taphonomy 2015, Stuttgart.
Schüßler, C., Bräuchler, C., Koch, M.A., Thiv, M. (2015): Two Macaronesian endemic genera, two different biogeographic histories: Gesnouinia and Visnea and the role of fossils in phylogenetics. FloraMac 2015, Gran Canaria.
Thiv, M., Kondraskov, P., Schütz, N., Schüßler, C., Menezes de Sequeira, M., Santos Guerra A., Caujapé-Castells, J., Jaén-Molina, R., Marrero-Rodríguez, A., Koch, M. A., Linder, P., Kovar-Eder, J. (2015): The complex evolution of Macaronesian laurisilva – new insights from molecular phylogenetics. FloraMac 2015, Gran Canaria.
Schüßler, C., Bräuchler, C., Thiv, M. (2015): Biogeography of Macaronesian-Mediterranean distributed Urticaceae. International Biogeography Society 7th Biennial Meeting 2015, Bayreuth
Thiv, M., Kondraskov, P., Schüßler, C., Schütz, N. (2015): Islands as refugia? - Are Macaronesian laurel forests 'Tertiary' relicts? 7th IBS Meeting, Bayreuth.
Schüßler, C., Freitag, H., Kadereit, G. (2014): Evolution of C4 photosynthesis and diversity of C4 and C3 leaf anatomy in Salsoleae s.s. (Chenopodiaceae/Amaranthaceae). BioDivEvo 2014, Dresden.
Research associate in the project The evolution of Macaronesian laurel forests, State Museum of Natural History Stuttgart
Research associate in the project Unionids of Baden-Württemberg, State Museum of Natural History Stuttgart
Lab technician for GBOL (German Barcode of Life) fungi, State Museum of Natural History Stuttgart
Acquisition of metadata (fungal collection), State Museum of Natural History Stuttgart
Internship in environmental education, Landesbund für Vogelschutz Muhr am See
PhD student at COS Heidelberg, supervised by Prof. Marcus Koch. Thesis: No Tertiary relicts? A biogeographical study on the Macaronesian laurel forest species in Daucus (Apiaceae), Geranium (Geraniaceae), Gesnouinia (Urticaceae), Phyllis (Rubiaceae), Semele (Asparagaceae) and Visnea (Pentaphylacaceae)
Diploma (Biology), Johannes Gutenberg-University Mainz. Main subjects: botany, genetics, ecology.
Thesis at the Institut für Allgemeine Botanik, supervised by Prof. G. Kadereit. Title: Evolution of C4 photosynthesis in Salsoleae s.str. and diversity of leaf types