A review of the taxonomy and DNA barcoding of the Diamesa latitarsis group (Diptera: Chironomidae: Diamesinae), with a description of two new species

Abstract

Two new species, Diamesa sangecha sp. nov. and D. demavendensis sp. nov., are described from the Caucasus and Iran, respectively. An overview of the current taxonomy of the Diamesa latitarsis group is also provided, integrating both morphological and molecular genetic data. This combined approach expands the morphological criteria traditionally used to define the D. latitarsis group. In addition, twelve new mitochondrial COI DNA barcodes were generated and analyzed in conjunction with all publicly available sequences of the D. latitarsis species group retrieved from NCBI GenBank and BOLD. Molecular data independently confirm the distinct species boundaries of D. demavendensis sp. nov. and D. sangecha sp. nov. Furthermore, the first DNA barcode for D. tskhomelidzei Kownacki et Kownacka reveals a close phylogenetic affinity to D. caucasica Kownacki et Kownacka, exhibiting a minimal interspecific K2P distance of 1.90%. Finally, we critically discuss the problematic cryptic species boundaries within the D. lindrothi–D. goetghebueri complex.