Molecular identification of termite assemblages at the source of the Okavango Delta in the Angola highlands

The National Geographic Okavango Wilderness Project aims to secure sustainable protection for the Okavango Delta and its waterways. With 95 % of water flowing into the Okavango Delta originating from the Angolan highlands, this water tower is of great importance, and biodiversity documentation is still in its infancy. As ecosystem engineers, termites play a pivotal role in the breakdown and recycling of organic matter. Termite assemblages in Angola are generally undocumented, and the highlands are no exception.

We sampled over 500 specimens in the open miombo, forest and wetland habitats in Angola’s Cuando Cubango and Moxico provinces, performing DNA barcoding of 242 specimens. Morphological identification was not attempted due to a lack of available taxonomic expertise. Therefore, we relied exclusively on DNA-based methods to infer the most likely taxon. BOLD Systems was utilised for sequence searches, and phylogenetic context was created using new and publicly available DNA barcodes obtained from other Southern African regions. Genetic clusters identified were assessed for intragroup genetic divergence.

The analyses placed the specimens in a total of three families (Kalotermitidae, Hodotermitidae and Termitidae) and four subfamilies of Termitidae (Apicotermitinae, Nasutitermitinae, Macrotermitinae and Termitinae), spanning 18 genera. Only 24.79 % of the sequences were identified to the species level, encompassing 13 species.

Our results represent the first attempt to document termite diversity at the source of the Okavango Delta and sets the baseline data for documenting termite diversity in Angola. We also highlight that the paucity of DNA sequence data for termites in Southern Africa severely hinders the construction of comprehensive biodiversity assessments.