top

Back to The Log Blog

SCARAB BEETLES: Brown Flower Beetle, Spotted Flower Chafer

Scarab Beetles

brown-flower

Brown Flower Beetle

October 2018 – on Grevillea ‘Moonlight’

Scientific name : Glycyphana stolata

When and where in yard: Seen during the day from mid-spring to early Autumn. On Grevillea ‘moonlight’, and Cosmos flower

Ready to launch into flight.

Observations : I love observing the flower beetles – the heavy-weights of the insect pollinators. The Brown Flower Beetles are often observed burying their head into the centre of a flower as if greedily scoffing a sweet pie. The grevillea moonlight shrub seems to be their favourite in my garden. For a period of one or two days in spring I’ve observed a gathering (over a dozen individuals) of these beetles in the grevillea in a feeding and mating frenzy. Even though they are quite large (around fifteen mm long) they can be difficult to spot because they sometimes wedge their heads so deeply into the centre of the grevillea flower. To get a photo of their heads you sometimes have to wait till they are ready to fly – at which point they climb to the end of the flower styles and launch into the air.

Bottoms up – Enjoying the nectar meal from the Cosmos flower

Fun facts: As a group the flower beetles are good flyers enabling them to buzz from flower to flower feeding on nectar. Flower beetles are superior flyers to most beetles as they don’t need to raise their wing covers (elytra) to extend their flight wings.

Return to top

spotted-flower

Spotted Flower Chafer

(other common name: Punctate Flower Chafer)

Dec 2018 on Cosmos flower.

Scientific name: Neorrhina punctatum (old name: Polystigma punctatum)

When and where in yard: Seen during day from late spring (Nov) to late summer (Feb). The Spotted Flower Chafer seems to have wider tastes than the Brown Flower Beetle. Seen on mint flower, Cosmos flower, Buckwheat flower and Grevillea ‘Moonlight’

Spanning two mint bush flowers

Observation : When you first hear and catch a glimpse of the Spotted Flower Chafer in flight it is easy to think it is a large bee because of the loud buzzing sound and the yellowish and black colouring. They seem more active and agile in flight than the Brown Flower Beetle. I only observed this beetle singly ie I didn’t see any gatherings like I did with the brown flower beetle.

A curl grub in our compost (June 2017), Larvae of Scarab beetle (not able to identify species)

Fun Facts : Like all scarab beetles the Cetoniinae (flower beetles) undergo a complete metamorphosis in their life cycle. From egg to larval grubs to pupae then adult beetles. The larval grubs are thick white grubs commonly called curl grubs. Flower beetles lay their eggs in rotting wood hollows or other sources of rotting vegetable matter such as a compost heaps. In our yard an area that had decomposing eucalypts mulch was a rich source of curl grubs. When we dug up this bed in spring we uncovered dozens of late instar curl grubs about 10-15 cm below the surface. There is very little information available on identifying larvae probably because it is very difficult to differentiate species at the grub stage.

Return to top

One Reply to “Beetles”

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: