Assemblage and diversity of euglenophytes in the intertidal pools along the southwest coast of India

Abstract

A contemporary taxonomical overview of the euglenophytes with significant insights into the euglenophyte genera and species diversity in the intertidal pools of the Southwest coast of India is provided. This study is the first to thoroughly examine euglenophytes in the interstitial water of five nearshore sandy intertidal pools, showcasing their diversity. It also builds on previous research conducted in India by providing insights into the physical and chemical parameters and the species composition of euglenophytes. A total of 31 species of euglenophytes belonging to two families (Euglenoidae and Phacaceae) were identified up to species level based on the cell morphology using standard identification keys, among which Euglenoidae dominated the most. Trachelomonas sp. was commonly observed across all stations in the study, likely due to its resilience, tolerance for high organic content, and status as a cosmopolitan thecate species. The variety, prevalence, and species diversity of euglenophytes within a particular area are shaped by temperature, salinity, pH, sunlight exposure, habitat features, climate, and various physicochemical and biological components. A positive correlation was confirmed between nitrate, phosphate, silicate, DO, pH, organic matter, total nitrogen, chlorophyll a, clay %, and silt % with euglenophytes' diversity and cell density.