Mustard Bellied Snake (Elapognathus rhodogaster). These tiny snakes grow to only about 30cm long - this appeared to be a young one, it was somewhat shorter than full size and less than 10mm thick (compare it against the lawn). It did not show any signs of aggression so my neighbour picked it up on a shovel, put it in a bucket, and we released it back in the nearby nature reserve. They are categorised as only 'mildly venomous'. Second shot in note.