Discovery of a New Endangered Freshwater Mussel Species in the Genus Chamberlainia Simpson, 1900 (Bivalvia: Unionidae) from Mekong Basin


  • Bangon Kongim Biodiversity and Traditional Knowledge Research Unit, Department of Biology, Faculty of Science, Mahasarakham University, Maha Sarakham, 44150, THAILAND
  • Chirasak Sutcharit Animal Systematics Research Unit, Department of Biology, Faculty of Science, Chulalongkorn University, Bangkok 10330, THAILAND
  • Ekgachai Jeratthitikul Animal Systematics and Molecular Ecology Laboratory, Department of Biology, Faculty of Science, Mahidol University, Bangkok 10400, THAILAND


conservation, endangered, pearl mussel, endemic, Thailand, Indochina


Chamberlainia somsakpanhai sp. nov., the largest freshwater bivalve (Unionidae) in the Mekong Basin, is described using morphological characters and molecular analysis. The new species differs from its congeners by having an ovate shell outline and obtuse and distinct sub-biangulate posterior margin. A multi-locus phylogenetic tree (mitochondrial COI and 16S, and nuclear 28S genes) recognized the new species along with other two members of genus, namely C. hainesiana and C. duclerci. Average genetic divergence between the new species and its congeners is 13.8–14.1% by an uncorrected COI p-distance.


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How to Cite

Kongim, B., Sutcharit, C. and Jeratthitikul, E. 2023. Discovery of a New Endangered Freshwater Mussel Species in the Genus Chamberlainia Simpson, 1900 (Bivalvia: Unionidae) from Mekong Basin. Tropical Natural History. 7 (May 2023), 242–250.



Original Articles