Physical contact between a native frog (Leiopelma pakeka) and a carnivorous land snail (Powelliphanta hochstetteri obscura): what was going on?

On 8 May 2018 at 23:15 h physical contact was observed between an adult carnivorous land snail (Powelliphanta hochstetteri obscura) and an adult Maud Island frog (Leiopelma pakeka) on Te Pakeka/Maud Island, Marlborough Sounds, New Zealand. The land snail (40-45 mm diameter) was on its back with its foot under the frog (38.5 mm snout-vent length), raising the possibility that this was a predation attempt by the snail. Carnivorous endemic land snails are only known to consume a range of invertebrate species, especially earthworms. Our observation suggests that these snails might also opportunistically attempt to consume small ground vertebrates, although definitive evidence is required.