DBG · Promoting young researchers

Anže Žerdoner Čalasan (Ludwig-Maximilians-Universität München)

Fig. C: Electron microscope image of Trachelomonas cells at different ontogenetic stages. Fig. F: Light microscope image of a Trachelomonas cell during hatching. Images: Anže Žerdoner Čalasan, LMU

Anže Žerdoner Čalasan's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Ludwig-Maximilians-Universität München (LMU) in the year 2017

Title of awarded thesis

"Morphological, phylogenetic and taxonomic analysis of selected Trachelomonas (Euglenida) strains"

Anže Žerdoner Čalasan clarified three taxa of Trachelomonas taxa that were validly described already 100 years ago. In doing this he was able to apply also genetic information for reliable species determination.

Euglenids are a very common and abundant group of predominantly freshwater microbial eukaryotes comprising of approximately 1,400 described species. One of the groups within the freshwater phototrophic presenters is Trachelomonas, which is together with Strombomonas the only group able to form an inorganic shell-like structure around its own body, named lorica. I cultivated six of Trachelomonas strains, which were collected in Dobrostany – a lake-rich region in western Ukraine – from which 52 species were described, but their identity is still unclear due to the lack of DNA information. Based on light and scanning electron microscopy and phylogenetic analysis, I provided a detailed morphological and genetic description of selected strains. Based on morphological comparisons with the type illustrations, I was able to apply genetic information to a specific name of a species already validly described 100 years ago. Despite taxonomy being seen mostly as a theoretical problem, one should not forget that it is the grounds for communication about organisms, and it is therefore impossible to answer fundamental biological questions without it.


Anže Žerdoner Čalasan conducted this work at the Institute / Chair Department I, Systematic Botany and Mycology in the working group of Prof. Dr. Marc Gottschling.