Diatoms (Bacillariophyta) of the world’s highest aquatic environments from the Western Himalayas, India

Abstract The present study is a preliminary taxonomic survey of diatom assemblages from one of the highest mountain ranges in the Western Himalayas – Ladakh. 37 samples were collected from 19 different sampling sites at altitudes ranging from 3100–4552 amsl. The diatom communities were representative of habitats such as lakes, streams, and hot springs from high altitudes. The dominant diatoms are studied using light microscopy and identified using valve morphometrics. The study enlists a total of 74 taxa belonging to 40 genera along with photomicrographic plates. Commonly-found species of high-altitude hot springs habitats were Gogorevia exilis and Denticula thermaloides. Reimeria sinuata, Fragilaria vaucheriae, Gomphonella cf. olivacea, Encyonema ventricosum, Lindavia biswashanti, Diatoma moniliformis, and Denticula valida were commonly occurring species in stream, river and lake habitats. Further analysis and putative novel species from this high-altitude environment will be described in future publications.