Unravelling genetic differentiation between Glossina brevipalpis populations from two distant National Parks in Mozambique

African trypanosomosis (AT), caused by protozoan parasites of the genus Trypanosoma, has plagued the African continent for centuries, affecting both humans and animals. Vector control represents an efficient way to reduce the burden of AT. In Mozambique, control campaigns reshaped tsetse fly distribution to what it is today, with Glossina brevipalpis and G. austeni as the dominant species in the South. Additionally, G. brevipalpis can be found in two National parks, Gorongosa National Park in the Centre and Maputo National Park in the South, with an 840 km wide tsetse-free zone between them. In order to improve our knowledge of the genetic diversity and gene flow of these populations and their probable isolation, we undertook a population genetics study with 11 microsatellite loci. We found that these two zones behave as isolated subpopulations, only exchanging a few individuals per year. To explain this finding, we suggest the existence of undocumented pocket populations between the two parks, or, in the absence of these, the accidental translocation of tsetse flies during human-driven animal transportation. We concluded that such undocumented means of dispersal should be explored further in studies investigating Glossina populations, to allow for the design of more efficient control strategies.