Halamphora witkowskii sp. nov. (Catenulaceae, Bacillariophyta), a new diatom species from the alkaline waters of Lake Van, Republic of Türkiye

This study introduces Halamphora witkowskii sp. nov., a newly discovered diatom species from Lake Van, the world’s largest soda lake known for its high alkalinity. Detailed morphological and morphometric analyses using light and scanning electron microscopy effectively distinguished this new species from closely related taxa, including Halamphora minima, H. coffeaeformis, and H. tumida. Additionally, culturing studies from live cells led to the establishment of two separate monocultures, which were utilized for phylogenetic analysis using the rbcL molecular marker, further confirming the distinctiveness of Halamphora witkowskii from other known species.