The name of this endangered native insect is a bit misleading! Robust grasshoppers (Brachapsis robustus) are not particularly robust nor very good at hopping, and they don’t live in the grass.
Found in several river catchments in the Mackenzie Basin, the Robust grasshopper relies on camouflage. They have a range of colour morphs, including grey, orange, and black. Grey is by far the most common and helps the grasshopper blend in perfectly with the rocky river basins it calls home. Spots of orange mean they look a bit like rocks with lichen growing on them.
Like other native grasshoppers, B. robustus has stumpy wings that are all but useless for flying. They can jump but not particularly well or gracefully – often landing in a clumsy back or belly flop. Rather than use all their energy jumping around, their first defence is freezing, relying on camouflage to keep them safe.
B. robustus lives for about two years, and females might lay up to 30 eggs in a season. They are vegetarians, eating mosses and lichens as well as leafier, greener plants. Not being fussy about what they eat might help them survive the punishing summer heat in the Basin. Unfortunately, Robust grasshoppers are easy prey for stoats, rats, and hedgehogs, and they are now listed as a threatened species. Fortunately, they’re now protected under the Wildlife Act (1953) and a conservation reserve was set up for them in 2017, one of the first invertebrate conservation reserves in the world!
Check these links for more info on Robust Grasshoppers in NZ
iNaturalist.nz: Observations of Brachaspis robustus
Wikipedia: Information on Brachaspis robustus