Description of carybdea sivickisi in NZ Coastal Invertebrates (volume 1, ed. Steve de C. Cook): Transparent bell with white nematocyst spots, stomach with 4 pouches, 4 interradial tentacles. Simple tentacles with rings of nematocysts and a small terminal bulb. Four pairs of gonads (pale yellow to orange). Able to attach themselves to objects with 4 adhesive pads on the aboral surface of the bell. Known to adhere to undersides of rocks during the day. Divers at GB reef reported being stung while observing them capturing prey at night. Stings cause swelling and blisters that persist for several hours.
I have seen a few free swimming along the south coast and in the #TaputerangaMarineReserve.