DNA Barcoding of genus Hexacentrus in China reveals cryptic diversity within Hexacentrus japonicus (Orthoptera, Tettigoniidae)

DNA barcoding has been proved successful to provide resolution beyond the boundaries of morphological information. Hence, a study was undertaken to establish DNA barcodes for all morphologically determined Hexacentrus species in China collections. In total, 83 specimens of five Hexacentrus species were barcoded using standard mitochondrial cytochrome c oxidase subunit I (COI) gene. Except for Hexacentrus japonicus, barcode gaps were present in the remaining Hexacentrus species. Taxon ID tree generated seven BOLD's barcode index numbers (BINs), four of which were in agreement with the morphological species. For Hexacentrus japonicus, the maximum intraspecific divergence (4.43%) produced a minimal overlap (0.64%), and 19 specimens were divided into three different BINs. There may be cryptic species within the current Hexacentrus japonicus. This study adds to a growing body of DNA barcodes that have become available for katydids, and shows that a DNA barcoding approach enables the identification of known Hexacentrus species with a very high resolution.