Population genetic structure of Etroplus suratensis Bloch, 1790 in South India: preliminary evidence of founder haplotypes shared among populations

Abstract

Indian estuarine and coastal water habitats have reduced in recent decades because of anthropogenic activities such as coastal development. The pearlspot cichlid Etroplus suratensis is designated as Least Concern, given its wide distribution and presumably large overall population size in South India, despite the declining trend observed in wild populations. To assess the genetic diversity and connectivity among South Indian coastal populations, mitochondrial displacement loop sequence analysis was conducted to provide fundamental information for future conservation studies and an understanding of population dynamics by calculating the haplotype diversity of local populations. The haplotype (h) and nucleotide (π) diversity were very low at most localities, with values ranging from 0.56061 to 0.87879 and from 0.0014 to 0.0046, respectively, which may have resulted from recent population bottlenecks or founder events. The results also revealed a clear genetic differentiation between East and West coast populations, suggesting the existence of a gene flow barrier between them. As the maintenance of genetic connectivity is a prerequisite for local population stability, the preservation of extant habitats and the restoration of water bodies along the coast of India may be the most effective measures for the sustainable maintenance of this species.