Species diversity of phlebotomine sand flies and sympatric occurrence of Leishmania (Mundinia) martiniquensis, Leishmania (Leishmania) donovani complex, and Trypanosoma spp. in the visceral leishmaniasis focus of southern Thailand

•Five species of sand flies, i.e., Se. khawi, Se. barraudi, Ph. stantoni, Gr. indica, and Se. hivernus, were systematically identified in the VL focus of southern Thailand.•This is the first molecular evidence of L. martiniquensis and L. donovani complex in Gr. indica and Ph. stantoni, respectively.•Anuran trypanosomes were also ubiquitously detected and phylogenetically divided into two major clades (An04/Frog1 and An01+An02/Frog2).•The novel finding indicates the co-circulation of trypanosomatid parasites and the possible role of sand flies for autochthonous transmission in southern Thailand.