Abstract:
Stink bugs are major pests of macadamia in South Africa. Accurate identification and
knowledge of species composition are important to inform management practices. The overall aims
of this study were to identify stink bug species from macadamia orchards in South Africa using
morphology, and to establish a DNA database based on the cytochrome c oxidase subunit 1 gene region.
A total of 21 stink bug species were found in macadamia orchards in KwaZulu-Natal, Limpopo and
Mpumalanga provinces. Bathycoelia distincta Distant, 1878, was the dominant species throughout all
three growing regions. Two unidentified species of Boerias Kirkaldy, 1909, here designated as Boerias
sp. 1 and Boerias sp. 2, were the second and third most abundant species found in KwaZulu-Natal.
No species of Boerias has previously been reported in association with macadamia. Evidence of a
cryptic third species of Boerias was also found. Species composition fluctuated over three growing
seasons in Limpopo and differed between the three growing regions during the 2019–2020 season,
highlighting the need for ongoing monitoring of these important pest species. The DNA barcode
database developed in this study will be valuable for future monitoring and identifications, including
cryptic or polymorphic stink bug species and different life stages.
