Coenagrion lindenii zernyi (Schmidt): an East Mediterranean taxon threatened with extinction by introgression from the West (Zygoptera: Coenagrionidae)

S and E of the Bay of Iskenderun in Turkey, C. lindenii (Sdl.) changes from the nominal subspecies to spp. zernyi Schmidt in an introgressive manner with the formation of genetic ‘islands’ rather than a stable dine. In populations in E Anatolia, imagos emerging early in the season are close to lindenii (i.e. large and dark), while those emerging later in summer, are zemyi. Thus, a different time of development and eclosion of the larvae restricts the gene flow between the 2 taxa, and slows down retrogression.