Extending the Holocene Record of Marine Diatoms in East Antarctica: Evidence from the Larsemann Hills

ABSTRACT

Accurate reporting of species distributions is fundamental to understanding ecological patterns in Antarctica; however, current knowledge of diatom biogeography remains incomplete, particularly in under-documented regions such as East Antarctica. Although the Larsemann Hills is a key site for palaeoclimate research in East Antarctica, systematic documentation of regional marine diatom assemblages, especially low-abundance taxa, is still limited and requires further investigation. This study presents a diatom-based analysis of a 200 cm sediment core (DL3) from Discussion Lake, spanning from ~ 6.9 cal ka BP to the present. We identified 43 taxa across marine, brackish, and freshwater assemblages, representing the Holocene diatom record preserved in the basin. Notably, we report eight marine diatom species for the first time from the region, although these taxa have been previously recorded in another region of Antarctica. This study refines the baseline understanding of regional diatom diversity and biogeography.