Mitogenomic diversity and phylogenetic characterization of Aedes albopictus (Diptera: Culicidae) populations from the Black Sea region of Türkiye.

Aedes albopictus (Skuse, 1894), the Asian tiger mosquito, is one of the most invasive mosquito species worldwide and an important vector of several arboviruses of public health concern. Although its distribution in Türkiye has expanded rapidly since its first detection, the mitogenomic diversity and phylogeographic relationships of Turkish populations remain poorly understood. Here, we provide the first mitogenome-based characterization of Ae. albopictus populations from the Black Sea region of Türkiye within a global comparative framework. Complete mitochondrial genomes were generated from 20 specimens collected along the Turkish Black Sea coast and analyzed together with 75 reference mitogenomes retrieved from GenBank. The Turkish mitogenomes ranged from 15.8 to 17.1 kb and exhibited the typical Ae. albopictus mitochondrial organization, including 13 protein-coding genes, 22 transfer RNAs, 2 ribosomal RNAs, and a control region. Gene order and orientation were conserved across all Turkish samples, and most size variation was confined to the control region. The mitogenomes were strongly AT-rich, and codon usage showed a marked bias toward A/U-ending codons. Phylogenetic analyses using concatenated sequences of all 13 protein-coding genes and both ribosomal RNA genes showed that Turkish samples were not monophyletic; rather, they were distributed among multiple subclades within the broad A1a complex. The results indicate high mitogenomic diversity and a mosaic phylogeographic structure, consistent with multiple maternal lineages contributing to Ae. albopictus populations in Türkiye's Black Sea region. The phylogenetic signature supports a scenario of multiple introductions of Ae. albopictus rather than spread from a single founding population.