Diversity and ecological significance of seaweeds along the Saurashtra coast of Gujarat, India: a five-year study (2019–2023)

India has a coastline of 7500 km, bordered to the south by the Indian Ocean, to the west by the Arabian Sea, and to the east by the Bay of Bengal. Gujarat, in particular, encompasses nearly 1600 km of coastal area, which supports a rich diversity of seaweeds and plays a crucial role in maintaining this biodiversity. This study investigated the diversity of seaweeds along the Saurashtra coast of Gujarat, India, over five years from 2019 to 2023, focussing on the distribution and ecological significance of various seaweed species. The observations included finding new and recurring species in the study area. The collected specimens were taxonomically identified, classified, and preserved in a herbarium. An updated checklist of seaweed species found along the Gujarat coast is provided with this paper. In total, the study recorded 225 species of seaweeds from the regions of Veraval, Okha, and adjacent areas. Among these, Rhodophyta was the most diverse, comprising 135 species, followed by Chlorophyta with 48 species, and Ochrophyta with 42 species. The highest diversity was observed in 2022, with 160 species recorded, surpassing other years. Additionally, the study identified 28 new species, including 16 that are first records for India, significantly enhancing the current understanding of Indian seaweed flora.