Tachysphex nigerrimus
Black cockroach hunter wasps can be found throughout Aotearoa|New Zealand, including Rekohu|Chatham Islands. As their name implies, the females hunt for native cockroaches (Celatoblatta spp), which they then drag back to their nest to feed to their larvae. Nests are constructed in shingle and sand on the banks of streams or coastal beaches. Cockroach hunter wasps are tiny and black, and because they nest near water sources, they often get mistaken for sandflies (though unlike sandflies or social wasps, hunting wasps won’t bite or sting).
Hunter wasps are considered solitary, thought multiple adults might construct their nest in the same area (referred to as a community). Communally nesting species can only end up in the wrong nest – is this a mistake or on purpose to steal food from a neighbor? Either way, the nest owner will quickly evict the intruder and the wasps will have a brief tussle. If you watch them long enough at these communal nesting sites, you’ll see some neat interactions!
Check these links for more info on the Black Cockroach-hunter Wasp in NZ
Wikipedia: Information on Tachysphex
CitScihub: Phil Bendle Collection
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