First genetic evidence of Aedes albopictus (Skuse, 1894) (Diptera: Culicidae) establishment and recent invasion in Honduras

Aedes (Stegomyia) albopictus (Skuse, 1894), is an invasive mosquito of growing public health importance in the Americas, yet its genetic diversity and invasion dynamics remain unexplored in several Central American countries including Honduras. This study provides the first genetic characterization of Ae. albopictus from Honduras by analyzing specimens collected from five municipalities using a multilocus approach combining mitochondrial (COI, NAD5) and nuclear (ITS2) markers. A total of 170 individuals were processed, yielding 68-87 high-quality DNA sequences per marker. Genetic diversity was low to moderate (0.1474-0.5863), consistent with a recent introduction followed by rapid expansion. Mitochondrial markers identified four COI haplotypes and two NAD5 haplotypes, while ITS2 revealed higher polymorphism. Concatenated COI + NAD5 sequences increased haplotype resolution, recovering seven haplotypes. Puerto Cortés population showed the highest diversity (0.7526) and concentration of private haplotypes (n = 2), supporting this major seaport as the most probable entry point of Ae. albopictus into Honduras. Haplotype networks and phylogenetic analyses indicated multiple introduction pathways, with affinities to Asian, North American, and Central American lineages. A novel NAD5 haplotype was identified, suggesting early-stage diversification after introduction. Population differentiation was generally low across sites, with heterogeneous but overall substantial gene flow. These results provide the first genetic baseline for Ae. albopictus in Honduras and highlight the need for expanded spatial sampling and genomic monitoring to understand invasion routes, population connectivity, and implications for arbovirus transmission and vector control.