This is one of a couple of easily confused species of damselfly in Australia with red-tipped abdomens, Agriocnemis pygmaea (Wandering Midget) being one of the others. It is a widespread damselfly ranging from India to China, south-east Asia, New Guinea and Australia.
Argiocnmis rubescens apparently prefers fresh still waters such as pools, marshes and swamps. We found a couple of examples in Cairns Botanic Gardens and Robert Road Park.
The adult is relatively small. When immature it is a pale reddish brown. The mature male is dark with pale green stripes on the thorax, and red on segments 8 and 9. Given my images below and the immature male/female colours, I am not completely sure about some of the genders shown. Shame on me.