Christmas Beetling About

BEETLING ABOUT

Australia is home to about 40 different kinds of Christmas beetles – how many have you seen? Local entomologist Dr Chris Reid reports.

Tis the season to be jolly and, with the rains over the last few months, beetles should be particularly jolly. Because of the rains there’s a big leaf flush going on right now (mid-November) and new leaves are much more palatable to leaf-eaters than old leaves.

The reason for that is accumulation of tannins as leaves get older – tannins are the same chemicals that make your tea, coffee, chocolate and red wine dark (and bitter) and they are also used to make leather out of animal skins. Tannins don’t taste good to many leaf-feeding animals so, for them, the new leaves are the way to go.

OK, that’s enough chemistry. What I was trying to say is that it ought to be a good summer for herbivorous insects, but I suspect that the very dry winter and early spring may have killed off a lot of the larvae of these insects.

One type of leaf-feeding insect is often particularly prominent at this time of year – the Christmas beetle. These are scarabs, with white curl grubs feeding on roots in the soil, that slowly

turn into adults in spring but rely on rains for the soil to be soft enough for them to push their way through to the surface.

There are about 40 different kinds of Christmas beetles in Australia. In the past I’ve seen seven different kinds at the local railway station lights, but so far this year, nothing. Hopefully they are just late, or my eyesight has deteriorated. Pictured below are some of the species I’ve seen locally.

If you want to know what these are, try identifying them using our free app (with great images by my colleague, Mike Burleigh). The app available for both android and iPhones. Search Google Play and Apple’s App Store for the “Xmas Beetle ID Guide” by the Australian Museum.

I’d be interested to hear about what you find locally.

Meanwhile, have a great Christmas.

n Have a question for Chris? Email editor@2515mag.com.au. 2515

Christmas beetles seen at Helensburgh Railway Station lights. Top left: Anoplognathus concolor (the Plain Christmas Beetle); top right: A. olivieri (Olivier’s Christmas Beetle); bottom left: A. porosus (known as The Washerwoman); bottom right: A. viriditarsus (known as The Queen Beetle).

Photos: Mike Burleigh, Australian Museum

10 2515 DECEMBER