author(s)
C Selvakumar, T Kubendran, KG Sivaramakrishnan and S Janarthanan

abstract
The aim of this study was to measure variation in the genetic structure for south Indian mayfly species, Petersula courtallensis with wide geographic ranges. The mtCOI sequences of 492–522 bp were obtained for eight individuals collected at eight different study sites during July 2014 to February 2015. Two clusters were resolved based on the distribution of individuals in the Neighbor-Joining tree. This south Indian mayfly species, P. courtallensis had high intraspecific differences between sites across wide spatial distribution. The results presented here support the conclusion that P. courtallensis is a species complex. Results also indicated that a general pattern of high genetic diversity between the western and eastern streams. The levels of COI diversity observed suggest the presence of two genetic distinct populations and their genetic diversity should be conserved in the long term.