Taxonomic exploration and molecular characterization of a novel Eleocharis species in Vietnam

This study investigates the morphological and molecular characterization of a newly discovered Eleocharis species collected from southern Vietnam, subsequently named Eleocharis bop. Initially mistaken for a variant of Eleocharis dulcis due to habitat similarities, E. bop was found to exhibit distinct morphological traits, including unique tuber characteristics, perianth bristles that are 2–3 times longer than the achene and small, isodiametric hexagonal to pentagonal epidermal cells on the achene. Molecular analysis using Internal Transcribed Spacer 1 (ITS1) sequencing and phylogenetic tree construction further confirms its differentiation within the genus. This species inhabits freshwater and slightly saline environments (salinity 1–4 ‰, pH 2–7) and is classified under the subgenus Limnochloa. Based on the findings, E. bop is likely a new species in Vietnam and the world. This research contributes to the taxonomic understanding of the genus Eleocharis and supports the goals of biodiversity conservation in line with the United Nations' Sustainable Development Goals (SDGs) 13.