Evolution and Morphological Diversity of the Genus Diploneis in Lake Malawi

by Hirak Parikh |

Lake Malawi, one of the world’s oldest and most ecologically significant freshwater systems, harbors exceptional biotic diversity. This diversity has been partly shaped by historical fluctuations in climate and lake levels, which have fostered the development of distinct ecological niches and microhabitats, driving diversification within the lake. Despite considerable research on animal groups, the evolutionary history of diatom-rich lineages in Africa, particularly in Lake Malawi, remains poorly understood. In this study, we utilized a combination of morphological, molecular, and paleontological data to explore species richness and evolutionary processes within the diatom genus Diploneis in Lake Malawi. Our comprehensive dataset revealed four putative new endemic Diploneis species from modern environments and two extinct species preserved in the lake’s fossil record (Parikh et al., 2024).

Morphological analyses showed that these newly identified species exhibit remarkable structural differences and unique patterns, similar to recent findings in Diploneis species from nearby Lake Tanganyika. Molecular phylogenetic analyses placed the four extant Diploneis species within a clade of Diploneis species from Lake Tanganyika but failed to recover a monophyletic group. This suggests that the new Lake Malawi Diploneis species likely originated from one or more ancestral lineages in Lake Tanganyika, indicating multiple colonization events. However, further analyses are needed to clarify their precise origins and evolutionary trajectories.

 

References:

Parikh, H., Stone, J. R., & Jovanovska, E. (2024). Evolution and morphological diversity of the genus Diploneis (Bacillariophyta) in Lake Malawi, with description of six new species. Phycologia, 63(5), 462-479.

I am Hirak Parikh, a Ph.D. candidate at Indiana State University, USA under the supervision of Dr. Jeffery Stone. I am the leader of the Diatom of the Month initiative and a Young ISDR member. I hold a Bachelor’s and Master’s degree in Biotechnology from India, where my fascination with diatoms began during my early undergraduate studies. Their intricate ornamentation initially drew me in, but I soon became captivated by their multidisciplinary significance and global ecological importance. I specialize in taxonomy, phylogeny, and phylogenomic, with a strong background in biotechnology. My research also focuses on advancing the bio-circular economy and leveraging biomonitoring techniques to assess environmental health and sustainability. My research sites include East Africa, the USA, and India.

 

Diploneis petila Parikh, Jeff.R.Stone & Jovanovska sp. nov.

Diploneis nyassaensis Parikh, Jeff.R.Stone & Jovanovska sp. nov.

Diploneis magna Parikh, Jeff.R.Stone & Jovanovska sp. nov.

Diploneis obessa Parikh, Jeff.R.Stone & Jovanovska sp. nov.