Uncovering the Diversity of Mesostoinae (Hymenoptera: Braconidae): A Glimpse Into the Australian Fauna Through a Study of Kangaroo Island

ABSTRACT The Mesostoinae are a poorly understood braconid subfamily with unresolved morphological challenges and a complex taxonomic history. This study provides insight into the biodiversity of this subfamily on Kangaroo Island (KI), South Australia. Specimens were curated from existing collection material for DNA extraction and sequencing of the mitochondrial cytochrome c oxidase subunit I gene. Molecular species delimitation provided initial characterisation of putative species, and relationships between these putative species were visualised using a maximum likelihood phylogenetic tree. Here, 28 putative species are recorded on KI, most of which are likely to represent undescribed taxa, which more than doubles the number of known mesostoine species in Australia. Two new species of Mesostoinae are described here: Austrohormius labeculus Tetley, sp. nov. and Hormiitis depressa Tetley, sp. nov. These results highlight that the diversity of Mesostoinae has been greatly underestimated in Australia and that further investigation on a larger scale will likely uncover many more Australian species.