Christmas Beetle is the Harbinger of the Festive Season


The arrival of these Christmas Beetles informs us that the festive season is on its way, but these beetles were photographed on a collection of Golden Cane Palms a few kilometres away at Cockatoo Hill Retreat.  It was our friend Carmen who discovered them amassed upon one of her flowering palms.  A quick search was made of our own Cooper Creek Golden Palms and nary a beetle was found.  We hear that the season is the reason for the appearance of these beautiful creatures.

Daintree Christmas Beetle

There are 34 different species of Christmas Beetle in Australia.  This specimen pictured above is probably Anoplognathus smaragdinus ohaus; Scarabaeidae; Rutelinae Green morph which is the most common, outnumbering other morphs in Australia.

Australian Christmas Beetles pupate late spring to early summer, from just below the surface of the soil.  Early rains in November have triggered the emergence of fully developed beetles, that break out of their pupae, emerging from the soil to swarm towards their food sources.  In this case, the burgeoning buds of the Golden Cane Palm (Dypsis lutescens), but around Australia gum trees are most affected.

XmasBeetle22013 has been dry, and without the early rains which moisten the soil, the beetles could have perished.  In cooler parts of Australia, Christmas Beetles take 2 years to emerge from their pupate form and to get together for a feeding and mating frenzy.  Winter rains enhance larval survival and after spring rains or thunderstorms mass emergence can often occur as the ground becomes moist enough for the adults to emerge.  Christmas beetles emerge late afternoon and can fly distances of several kilometres. Most flights occur at dusk, with beetles often attracted to outdoor lighting.

Christmas beetles are voracious feeders, making zigzag cuts and shredding the leaves.  Trees can be defoliated when beetles arrive in swarms, and repeated annual swarms affecting the same trees, may lead to dieback and even death of chosen trees.

The feeling of optimism that these iridescent Christmas beetles bring is attributed to the reminder that the season of festivity and good will is on its way.  Time to send out our Christmas newsletter.

One Response to “Christmas Beetle is the Harbinger of the Festive Season”

  • admin says:

    It’s always good to receive responses to our newsletters, especially when it provides additional information and definite identification such as this snippet of an email from entomologist, Geoff Monteith.

    Hello Neil
    Love your website, always things of interest,especially in the insect world which of course is what has me hooked. Those are absolutely spectacular pix of the green beetles on the golden cane inflorescence. Others may have already pointed it out to you, but they aren’t actually Christmas Beetles. Christmas beetles belong to a subfamily of the scarabs called the Rutelinae…their larvae live in soil and feed on living roots of plants and the adult beetles feed on leaves of trees. What you have there is another subfamily of the scarabs called the Cetoniinae (common name Flower Chafers)…their larvae live in and feed on rotten wood and humus, and the adults feed on sweet liquids such as nectar or fementing juices. The way you can tell them apart is that Xmas beetles are straight across the back of the thorax, whereas the flower chafers have that v-shaped backwards projection in the middle. The species in your picture is Ischiopsopha wallacei Thompson. A couple of years ago I saw a similar aggregation of them feeding on massed fermenting fruits up the trunk of a cluster fig at Iron Range….it was the loud buzzing which drew me to the tree in the first place.

    Thanks Geoff for this wonderfully informative response.

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