Member of SCNAT

Under the umbrella of the SSS, biologists from different fields are dedicated to the interests of systematics and taxonomy. The SSS serves as a competent contact for the scientists and the society, and maintains an international exchange.more

Image: C.Schüssler, stock.adobe.commore

Past Master Prizes

Connarus

Best master’s thesis award 2022

This year's best master’s thesis award was given to Serafin Streiff for his work entitled "Herbarium phylogenomics, taxonomy and floral evolution in Connaraceae ", conducted at the University of Basel.

Connaraceae is a poorly studied, pantropical angiosperm family that is particularly diverse in complex reproductive systems, such as di- and tristyly. However, a lack of molecular phylogenetic framework and stable taxonomy, especially in the tribe Cnestideae, precludes further research on this family. We leverage recent advances in sequencing herbarium specimens to greatly expand the molecular sampling of Cnestideae using the Angiosperms353 target enrichment approach. Based on our well-supported phylogeny, we find Cnestidae is monophyletic, but the largest genus, Rourea is polyphyletic. In a formal taxonomic revision of the tribe, we propose a new circumscription of Rourea, accepting the genera Byrsocarpus, Roureopsis, Santaloides and Santaloidella, and an amended Rourea s.str. Together with previously recognised Agelaea, Cnestis and Pseudoconnarus, all phylogenetically strongly supported and morphologically characterised, these genera now form the tribe Cnestidae. Moreover, we document that reproductive system evolution is rather labile, but we cannot statistically differentiate between a scenario where tristyly or distyly is ancestral. Based on morphological evidence, we consider ancestral tristyly with multiple transitions to distyly more plausible. Finally, in congruence with previous theories, we infer Connarceae to have dispersed out of Africa to other tropical regions both by geodispersal and long-distance dispersal, resulting in its present pantropical, disjunct distribution. Overall, our updated taxonomy increases ease of identification, and in combination with the phylogeny it also enables future research into evolutionary aspects of this family.

Leaves types
Image: Elin Rütimann

Best master’s thesis award 2021

This year's best master’s thesis award was given to Elin Rütimann for her work entitled "The adaptive significance of the mimosoid bipinnate leaf ", conducted at the University of Zürich.

I investigate these general questions for one specialized leaf type, the bipinnate leaf in legumes, using the mimosoid legume genus Albizia, with 90 species, as a study group. Specifically, I aim to characterize bipinnate leaf variation and overall leaf morphospace, including developing several indices to quantify leaf dividedness, test whether the observed variation is associated with climate, biomes and geography, and explore the evolution of this quantitative leaf variation, to gain insights into the potential adaptive significance of the mimosoid bipinnate leaf. My results are very much in line with the idea that almost all plant traits have evolved multiple times independently and that this ability to repeatedly reinvent traits underpinned the evolutionary success of the flowering plants. Such scenarios of repeated evolution of traits linked to evolutionary success provide a powerful framework for understanding the links between phenotypic trait evolution and evolutionary diversification.


Synema globosum
Image: wikipedia

Best master’s thesis award 2020

This year's best master’s thesis award was given to Karin Urfer for her work entitled "DNA barcoding and morphological analyses uncover large intraspecific variation in the crab spider Synema globosum (Araneae: Thomisidae) ", conducted at the Naturmuseum St. Gallen.


Otala punctata
Image: wikipedia

Best Master thesis 2019

This year's best master’s thesis award was given to Jeannette Kneubühler for her work entitled " Anatomical and phylogenetic investigation of the genera Alabastrina Kobelt, 1904 and Otala Schumacher, 1817 (Stylommatophora: Helicidae) ", conducted at the University of Bern.

This study delivers new insights in the anatomy of genital organs of some large helicid gastropods from Northern Africa. The separate taxonomic position of Siretia Pallary, 1926 from Otala as a genus within the Otalini G. Pfeffer, 1930 could be confirmed. We could show that the genus Alabastrina differs from all other genera by possession of a penial appendix. This character state was also found in the species A. tistutensis Galindo, 2018, which was collected at the type locality. Examination of the twin penial papilla system in Otala recovered a reduction of the proximal penial papilla in O. punctata. The genetic analysis with the markers COI, 16S, H3, and ITS2 revealed a high support for Alabastrina, Siretia, and Otala as separate evolutionary lineages within the Otalini. “Tingitana minettei decussata” clusters within the xanthodon-clade and confirms that the genus Tingitana can be synonymised with Otala.


lichen
Image: M. Bolliger

Best master’s thesis award 2018

The master’s thesis award was given to Maud Oïhénart for her work entitled "Lichens and bryophytes from the canton of Geneva’s old stonewalls - a floristic and ecological study ", conducted at the University of Geneva and at the Conservatoire et Jardin botaniques de la Ville de Genève.

[Résultat de recherche d'images pour "lichen mur genève"] Surveys were conducted on 46 stonewalls from the canton of Geneva. The laboratory work that followed data collection allowed for the identification of 30 bryophytes, 114 lichens and 12 vascular plants, for a total of 156 different species. Among those species, four bryophytes and 15 lichens were new to Geneva, and nine lichen species were new for Switzerland.

These floristic results were published in the journal Herzogia in 2018, with Maud as the lead author. Her study also highlighted the environmental factors (inclination, orientation, exposition, humidity, light, etc.) and structural factors (type of wall, of rock, or mortar, etc.) that influence the number or the type of lichens and bryophytes species present on walls. Her work provided an important contribution to the knowledge on these little-studied organisms.


Euglypha

Best master’s thesis award 2017

This year's best master’s thesis award was given to Clément Duckert for his work entitled " Morphological and molecular taxonomy of Euglypha – Toward a calibration of the molecular clock ", conducted at the Universities of Neuchâtel and Lausanne.

The genus Euglypha is composed of testate amoebae that can be found in a broad variety of soil and freshwater environments. Because of their small size, species identification can be reliably achieved only based on good quality light or scanning electron microscopy. Clément and co-workers demonstrated that the species Euglypha rotunda (the most common and widespread member of the genus) is not monophyletic based on morphology as well as molecular data. Their molecular clock analysis showed that the genus Euglypha appeared during the Jurassic and that some of these species have diverged very recently. This thesis convinced the jury by its thorough application of modern systematic methods to a poorly known taxon.


Ansonia_teneritas

Best master’s thesis award 2016

This year the best master’s thesis award was given to Lea Waser for her work entitled "From a lost world: phylogeny of the genus Ansonia Stoliczka, 1870 (Lissamphibia: Anura: Bufonidae) and the description of a new species including its morphometric discrimination", conducted at the Naturhistorisches Museum der Burgergemeinde Bern.

During herpetological surveys carried out in the interior of Sarawak, East Malaysia, several individuals of a small species of frogs (genus Ansonia Stoliczka 1870) were collected on the Usun Apau plateau and in the Gunung Hose mountain range. An integrative taxonomic approach comprising phylogenetic (2.4 kb mitochondrial rDNA fragment, Bayesian Inference and Maximum Likelihood, >5.1 % to its closest relative) and morphometric analyses (25 measurements, multivariate ratio analysis and linear discriminant analysis), as well as morphological comparisons support the status of a new species.


Scorpion

Best master’s thesis award 2015

This year best master’s thesis award was given to Lucie Cauwet for her work entitled " Morphology, function and evolution of male genitalia (hemispermatophores and spermatophores) in the Superfamily Scorpionoidea Latreille, 1802 (Chelicerata, Scorpiones)", conducted at the Université de Genève & Muséum d’histoire naturelle de la Ville de Genève. This thesis presents a thorough examination of scorpion spermatophores and hemi-spermatophores: Lucie explored structural homologies across the order and proposed a revised nomenclature for scorpion spermatophores and hemi-spermatophores. She also used a maximum parsimony reconstruction of their evolution by mapping characters on an existing phylogeny, and retrieved synapomorphies for taxa at different phylogenetic levels.

Madagascar flora

This year, we also rewarded a second Master thesis, Anahita Aebli, for her work entitled “Assembly of the Madagascan biota by replicated adaptive radiations: Case studies in Leguminosae-Mimosoideae”, conducted at the Institute of Systematic Botany, University of Zürich. Anahita investigated geotemporal trajectories of diversification in Madagascan mimosoid legumes via a comparative study of two species-rich Madagascan clades, the informal Dichrostachys group and Mimosa. She used genome-wide RADseq data to reconstruct densely sampled phylogenies for these two clades, and inferred for both groups a contemporaneous late Miocene colonization of Madagasacar followed by an early burst of diversification.


Beanka Forest Madagascar

Best master’s thesis award 2014

This year best master’s thesis award was given to Ralph Bolliger for his work entitled "Etude de la forêt de Beanka, une formation karstique de l’ouest de Madagascar: composition floristique et biogeographie", conducted at the Université de Genève & Conservatoire et Jardin botaniques de la Ville de Genève.

This thesis summarized six months of fieldwork on this little-known karstic region, and resulted in a global floristic analysis of the forest, along with the description of species new to science.