Phylogeny and species delimitation of the genus Longgenacris and Fruhstorferiola viridifemorata species group (Orthoptera: Acrididae: Melanoplinae) based on molecular evidence

Phylogenetic positions of the genusLonggenacrisand one of its members, i.e.L.rufiantennusare controversial. The species boundaries within both ofL.rufiantennus+Fruhstorferiola tonkinensisandF.viridifemorataspecies groups are unclear. In this study, we explored the phylogenetic positions of the genusLonggenacrisand the speciesL.rufiantennusand the relationships amongF.viridifemoratagroup based on the 658-base fragment of the mitochondrial gene cytochrome c oxidase subunit I (COI) barcode and the complete sequences of the internal transcribed spacer regions (ITS1andITS2) of the nuclear ribosomal DNA. The phylogenies were reconstructed in maximum likelihood framework using IQ-TREE. K2P distances were used to assess the overlap range between intraspecific variation and interspecific divergence. Phylogenetic species concept and NJ tree, K2P distance, the statistical parsimony network as well as the generalized mixed Yule coalescent model (GMYC) were employed to delimitate the species boundaries inL.rufiantennus+F.tonkinensisandF.viridifemorataspecies groups. The results demonstrated that the genusLonggenacrisshould be placed in the subfamily Melanoplinae but not Catantopinae, andL.rufiantennusshould be a member of the genusFruhstorferiolabut notLonggenacris. Species boundary delimitation confirmed the presence of oversplitting inL.rufiantennus+F.tonkinensisandF.viridifemorataspecies groups and suggested that each group should be treated as a single species.