Molecular identification of bat fly species and associated Bartonella bacteria from Lopburi and Sa Kaeo Provinces in Thailand

Bat flies harbour several species of bacteria, including Bartonella. We examined 50 bat flies collected from five species of cave-dwelling bats (Eonycteris spelaea, Hipposideros larvatus, Taphozous theobaldi, T. melanopogon and Rousettus sp.) in Lopburi and Sa Kaeo Provinces, Thailand. Four bat fly species in Streblidae (Brachytarsina cucullata, n = 18; B. macrops, n = 6; Megastrebla gigantea, n = 2; and Raymondia sp., n = 7) and one species in Nycteribiidae (Eucampsipoda latisterna, n = 17) were detected. The results of phylogenetic analyses of the COI, COII, 16S rRNA, and 18S rRNA gene sequences of these samples supported their morphological characteristics. They also provided the first molecular identification of these bat fly species and a new record of M. gigantea in Thailand. Molecular analyses of Bartonella from these bat flies using multigene analysis of five target markers (gltA, ITS, rpoB, nuoG and ftsZ) revealed a bacterial prevalence of 48%. Phylogenetic analyses identified six Bartonella species groups. They were related to those previously reported from Thailand and elsewhere in Asia and Africa. Interestingly, one group clustered with the potentially zoonotic species Bartonella rousetti found in Nigeria and Zambia. These findings highlight the rich biodiversity, particularly in terms of parasite-vector-host relationships, in the tropical climate of Thailand and Southeast Asia.