First occurrence records and molecular identification of <i>Sergentomyia</i> spp. (Diptera: Psychodidae) sand flies in Praia, Santiago Island, Cabo Verde (2024)

Phlebotomine sand flies are important vectors of pathogens affecting both humans and animals and are widely distributed geographically. In Cabo Verde, research on vector-borne diseases has focused primarily on mosquitoes, leaving other potential vectors understudied. As part of the ONESVEC surveillance project, we conducted a preliminary assessment to determine the presence of sand flies in Cabo Verde. From February to December 2024, entomological surveys using BioGents-Sentinel traps were carried out in five neighborhoods of Praia, Santiago Island: Achada Eugénio de Lima, Ponta de Água, Taiti, Vale do Palmarejo, and Vila Nova. Male specimens were slide-mounted for morphological identification, and randomly selected individuals underwent mitochondrial cytochrome c oxidase subunit I (COI) gene sequencing. Haplotype diversity and species delimitation (DnaSP, ASAP) were also assessed. A total of 367 sand flies (184 males, 173 females) were collected, of which 168 males were successfully identified. Most specimens were Sergentomyia fallax, found in all neighborhoods, while S. squamipleuris was identified in Taiti and Vale do Palmarejo. Phylogenetic analysis showed Cabo Verde S. fallax forming a well-supported monophyletic group, distinct from North African and Cyprus-Saudi Arabian lineages. Haplotype analysis revealed high haplotype but low nucleotide diversity, suggesting a genetically diverse yet stable or expanding population. In contrast, S. squamipleuris sequences clustered with Kenyan isolates in separate subclades, consistent with higher nucleotide diversity. ASAP species delimitation supported the phylogenetic analysis. This study provides the first confirmed record of phlebotomine sand flies in Cabo Verde and highlights the need for expanded surveillance and pathogen screening across the archipelago.