2025 Luc Ector Award – Yogeshwaran M
Filling the phylogeny of Cymbellales to trace their evolutionary trajectories
I am Yogeshwaran M, a PhD scholar at the Agharkar Research Institute (ARI), Pune, India, working under the supervision of Dr. Karthick Balasubramanian. My research focuses on the evolutionary history and biogeography of freshwater Gomphonemoid diatoms, with particular emphasis on the Western Ghats biodiversity hotspot. I integrate morphological taxonomy and molecular phylogenetics to investigate microbial endemism and diversification in tropical mountain ecosystems.
Freshwater diatoms often show striking patterns of endemism, especially in biodiversity hotspots such as the Western Ghats of India. One of the most exciting recent discoveries from this region is Indiconema, a newly described diatom genus that is currently known only from India. However, its evolutionary placement remains unresolved due to the lack of molecular data.
With the support of the ISDR Luc Ector Grant, this project aims to generate the first molecular dataset for Indiconema using the widely applied markers rbcL and 18S, and to reconstruct its phylogenetic relationship with Afrocymbella, an African lineage that has 
been hypothesized to be closely related based on morphology. This work will be carried out in collaboration with Dr. Elena Jovanovska (University of Basel, Switzerland), who is currently working on Afrocymbella. By integrating new Indian data with African lineages, we aim to test whether Indiconema and Afrocymbella represent closely related genera within Cymbellales and to clarify their evolutionary relationship.
By filling this missing branch in the Cymbellales phylogeny, this study will contribute to a better understanding of diatom evolution and biogeography.
I am grateful to the International Society for Diatom Research for supporting my work through the Luc Ector Grant. This award will be a major step in advancing my PhD research and strengthening international collaboration in diatom systematics.