Unified Morphological and Genetic Analyses Confirm the Existence of the Dwarf Snakehead Channa shingon (Anabantiformes: Channidae), in Kachin State, Myanmar

Abstract

Prior to this study, Myanmar was known to host 15 species of snakehead fishes (genus Channa) distributed across Southeast Asia. The region, characterized by its confluence of diverse river systems and two biodiversity hotspots, is presumed to have notable gaps in its biodiversity assessments. Recently, a new snakehead species, Channa shingon, was discovered in China, with its potential distribution in Myanmar warranting further investigation. This study focused on exploring Channa species in Kachin State and examined collected specimens using an integrated approach. The specimens were identified as C. shingon based on their distinct morphological characters, with a maximum standard length of 99.2 mm. Additionally, mitochondrial COI sequence data were generated, and species confirmation was achieved through nucleotide BLAST searches, genetic distance estimations, and phylogenetic analyses. The DNA sequences of C. shingon showed a mean inter-species genetic distance of 7.97% to 27.41% compared with other Channa species in the dataset, while the intra-species genetic distance between the Burmese and Chinese populations was 0.27%. Both Bayesian and maximum-likelihood phylogenetic analyses distinctly separated C. shingon from other congeners through a monophyletic clustering pattern, revealing its sister relationship with C. rubora. Overall, this study provides the first report of C. shingon from Myanmar and suggests its speciation from a common ancestor with C. rubora, likely driven by geographical barriers such as the Irrawaddy River. Furthermore, the study contributes a robust DNA barcode dataset encompassing 85.7% of the global Channa species diversity, which can serve as a valuable resource for further species identification, discovery, and diversity assessments of snakeheads from South and Southeast Asia.