Indication of cryptic taxa within the flat needlefish, Ablennes hians based on analysis of the cytochrome oxidase I region on a wide range of samples

We analysed the genetic structure with respect to geographic distribution of the flat needlefish, Ablennes hians, previously considered as having a circumtropical distribution. Cytochrome oxidase I (COI) barcode region sequences were constructed for a specimen from the Mediterranean, and a specimen from Japan. The sequences of the studied specimens were compared with 18 barcodes of this species from Barcode of Life Data-systems (BOLD). The results revealed that genetic distances between groups of specimens from different geographic regions can be as high as 10.9%, and in most comparisons were above the widely accepted threshold level of within-species variation. This suggests the occurrence of several cryptic taxa within the Ablennes hians complex.