On the possible synonymy of two Protracheoniscus species (Isopoda: Oniscidea): molecular and morphological clues

Abstract

. Two morphologically similar terrestrial isopod species, Protracheoniscus nogaicus Demi-anovitcz, 1932 and P. darevskii Borutzky, 1975, are evaluated for possible conspecifity in term of available molecular data using the protein coding mitochondrial gene cytochrome c oxidase I (COI) based on the Iranian and Russian material. The two species are clustered in a same clade on phylogenetic trees. Moreover, the K2P genetic distance between these two nominative species (2.2%) placed within intraspecific variation achieved in congeneric species. Low interspecies ge-netic distance along with the shallow reported morphological variations, criticizing the distinct position of P. darevskii , rather suggested it as a potential synonym of P . nogaicus . However, for a firm taxonomic interpretation, fresh material from topotype of P. nogaicus has to be explored in an integrative manner.