Species delimitation and molecular phylogeny of the grasshopper subfamily Gomphocerinae (Orthoptera: Acrididae) from Algeria based on mitochondrial and nuclear DNA markers

Abstract

Gomphocerinae grasshoppers (Orthoptera: Acrididae) are generally characterised by their polymorphism and cryptic diversity, which can be confusing when relying on morphological identification alone. DNA taxonomy serves as a powerful molecular tool for species identification and biodiversity assessment. In the context of zoogeography and the biodiversity conservation of animal resources in ecosystems, DNA barcoding data for Algerian Gomphocerinae fauna remains limited in global databases, despite their agroeconomic and environmental importance. Therefore, in this study, we collected various species of this subfamily from the Biskra region in Algeria and conducted DNA barcoding analysis, employing different molecular species delimitation methods (the automatic barcode gap discovery, assemble species by automatic partitioning, single-threshold general mixed Yule coalescent model, Bayesian Poisson tree process and multi-rate Poisson tree process methods), as well as phylogenetic analyses (maximum-likelihood and Bayesian inference) based on two molecular markers (COI and ITS). The results of the 163 newly generated sequences demonstrated that DNA barcoding technology is highly efficient and valuable for species identification in the subfamily Gomphocerinae, showing strong congruence with morphological evidence for 12 species, including eight species that were sequenced for the first time. This study also reported a new record of the genus Stenohippus Uvarov, 1926 in Algeria, comprising two species. Additionally, taxonomic revision allowed the species Dociostaurus biskrensis Moussi & Petit, 2014, to be transferred to the genus Stenohippus. Molecular tree analyses revealed the phylogenetic positions of the newly sequenced species within the subfamily Gomphocerinae and provided insights into their evolutionary relationships. These new data serve as a starting point for future research in other geographical areas, enabling a better understanding of the biodiversity of this insect group in Algeria.