Judged from colour, size, length of the antennae and the area I found this unfortunate prey, it may possibly be a common garden katydid nymph (Caedicia simplex). And the hunter would have been a garden orb-weaving spider (Eriophora transmarina). It is their usual spots to spin the web and wait for their victims in the night. They are fed by sucking the vital juice of the meal they have caught as this unlucky six-legged creature. Spiders play an important role in the food chain, controlling insect population.