A Review on Cytogenetically Studied Species of Family Coenagrionidae (Odonata: Zygoptera)

Abstract

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.