Diversity and Geographical Distribution of Coralline algae in China: A Comprehensive Literature-Based Assessment

Coralline algae are important calcifying red algae that contribute substantially to marine ecosystem structure and biogenic reef formation. However, their species diversity and geographic distribution in China remain poorly documented due to their extensive calcification, morphological convergence, and ongoing revisions of taxonomic frameworks. In this study, we reviewed published Chinese and English literature from 1980 to 2026 using Web of Science and the China National Knowledge Infrastructure (CNKI), with the literature search completed on 2 July 2026. By integrating species records, taxonomic revisions, and regional distribution data, we assessed the diversity and spatial distribution patterns of coralline algae in China. Historical records were revised by incorporating updated taxonomic information, including corrections of synonyms and taxonomic changes, resulting in an updated and verifiable checklist of accepted species. Our results showed that 109 coralline algal species, belonging to 30 genera, 8 families, and 3 orders, are currently recorded in China. Among these taxa, Corallinales contains the highest species diversity, Corallinaceae represents the most species-rich family, and Jania is the most species-rich genus. Taiwan, Hainan, and Sansha exhibit relatively high species richness, whereas differences among regions may be associated with variations in survey intensity. Spearman correlation analysis revealed a positive relationship between regional publication numbers and recorded species richness, suggesting that current understanding of coralline algal diversity in China remains influenced by sampling effort. This study provides an updated assessment of coralline algal diversity and spatial distribution patterns in China, establishing baseline information for future taxonomic research, biodiversity assessments, and conservation efforts.