Cytotaxonomy is useful for separating sister and cryptic species as well as for figuring out the evolutionary relationship between taxa. Family Coenagrionidae is considered as one of the largest zygopteran families under order Odonata. Globally, a lot of investigation has been undertaken on the family Coenagrionidae and significantly contributed by biologists throughout the world. Type number of the family Coenagrionidae is n=14 with XO-XX type of sex determining mechanism. Karyotypic variations within and between species are observed due to chromosome breaks and fusions, absence/presence of m chromosomes because of the holokinetic nature of chromosomes. Cytogenetically, 107 coenagrionid species have been studied all over the world which also includes 37 species from India. Among these, most of the species possesses n=14 haploid complement, while variation in chromosome number has been observed in 25% species.

Taxonomically, identification of complex taxa based on external morphological characters may leads to wrong identification of unknown organism at species level because these characters may also be altered due to geographical and seasonal variations. To overcome this molecular taxonomy has been emerged. In India, out of 9 morphologically described species of genus Ischnura (Odonata: Coenagrionidae), Ischnura senegalensis is the only species, which has been barcoded on the basis of COI gene. During the present study, mitochondrial COI gene has been barcoded for four species of genus Ischnura (Ischnura aurora, Ischnura forcipata, Ischnura rufostigma and Ischnura senegalensis), collected from fresh water bodies from the states of Punjab and Himachal Pradesh (India). Across the final alignment of COI sequences of 352bp, there are 282 conserved sites (80.1%), which represents that COI gene is highly conserved. Conspecific species show <1% divergence range (0% to 0.6%) and interspecific divergence ranges from 7.5% to 15.6%. COI gene sequences of all the species shows 95 – 100% similarity with the sequences of conspecific species deposited in GeneBank. Mitochondrial COI gene based DNA barcoding has been done for Ischnura aurora, Ischnura forcipata and Ischnura rufostigma for the first time from India and for Ischnura forcipata throughout the world.