Sergentomyia (Neophlebotomus) chattiensis n. sp.: morphological and molecular description of a new sand fly species from Himachal Pradesh, India.

INTRODUCTION: Himachal Pradesh, an ecologically diverse state in northern India, has recently emerged as a focus of atypical cutaneous leishmaniasis. As part of a molecular xenomonitoring, systematic entomological surveillance of sand flies resulted in the reporting of a novel species, Sergentomyia (Neophlebotomus) chattiensis n. sp. (Diptera: Psychodidae), from Chatti village in Kullu district, Himachal Pradesh, India.

METHODS: A systematic cross-sectional entomological survey was carried out in the districts of Kinnaur, Kullu, Shimla, and Mandi during August 2022, employing standard sand-fly collection techniques. Molecular characterization was performed using mitochondrial cytochrome c oxidase subunit I (COI) gene-based DNA barcoding, followed by phylogenetic analysis of the generated sequences.

RESULTS: The study reports Sergentomyia (Neo.) chattiensis as a newly recorded sand fly species and discusses its taxonomic association with other members of the subgenus Neophlebotomus. COI-based phylogenetic assessment confirmed that the collected specimens form a single taxonomic unit with negligible intraspecific genetic variation, while a genetic divergence of 12.3% from its closest congener supports its designation as a distinct species.

DISCUSSION: Despite its diverse physiography, rich biodiversity, and ecological suitability for sand fly breeding, Himachal Pradesh has lacked systematic entomological surveillance. The present study contributes to bridging this gap by expanding the existing knowledge of sand fly fauna in the state and providing comprehensive morphological and molecular characterization of this newly described species.