Spotted Flower Chafer - Neorrhina punctatum (Polystigma punctatum)

FAMILY SCARABAEIDAE

This page contains information and pictures about Spotted Flower Chafers that we found in the Brisbane area, Queensland, Australia.


Body length 20mm

This beetle was once called Polystigma punctatum. We first found this beetle when it rested on the Hibiscus leaf in our backyard in early summer. The beetle is pale brown in colour with many large black dots on its thorax and wing covers.

On early summer Nov 2008 in Karawatha Forest Rocky Circuit, near a large dead tree trunk, we saw some large bees flying to and from the tree trunk. We thought there must be a bee nest inside the tree trunk. We came close with cautions but did not found any bee nest. All we found was two Spotted Flower Chafers flying around, looking for some landing place on the rotten tree trunk.



The Spotted Flower Chafers, when on flight, are golden yellow in colour with black banded abdomen. They fly with hovering pattern like a bee, this is why we were miss-leaded. The Spotted Flower Chafers obviously mimicking bees. This is very common for an flower attending insect mimicking bees or wasps.



From the shape of their antenna, the two chafers were male. Since their larvae are known feed on and pupate inside rotten wood, the two males might have sensed a female was about to hatch inside the rotten tree trunk.

Reference:
1. A field guide to insects in Australia - By Paul Zborowski and Ross Storey, Reed New Holland, 1996, p116.
2. Beetles of Australia - Trevor J Hawkeswood, Angus & Robertson Publishers, 1987, plate 43 (Polystigma punctata).
3. Neorrhina punctatum (Donovan, 1805) - Australian Biological Resources Study, Department of the Environment, Water, Heritage and the Arts, 2002.