
This is from a forestry website – full info and more photos can be seen there.
I thought I would
delight bore educate enlighten you with some information about the grubs I pictured yesterday: Spitfire caterpillars, larvae of our Australian native Steel Blue Sawfly (Order Hymenoptera). I’ve gathered information from Museum Victoria, Wikipedia, CSIRO, a Forestry site, and a South Australian Government website.
The sawfly is a wasp, related to the Cherry and Pear Slug. It has a stocky body, usually a dark metallic blue, and does not sting. It has a double pair of wings with a span of about four centimetres. The adults are rarely seen, and spend their time hanging around their host tree. The sawfly gets its name from the saw-like ovipositor of the female. She opens holes in the underside of the leaf and lays her eggs.
The Spitfire larvae, about 8 centimetres long, love their tucker. Mainly active around late winter and spring, they sprawl around enmasse during the day, but at night they disport around the tree chomping gum leaves. They can gather into groups of as many as two hundred.When threatened, they raise their heads and exude a yellow-green liquid, strongly flavoured by eucalyptus oil extracted from the gum leaves.

Crossing Concrete at Brisbane 2012: By Tzedragon (Captured on iPhone) [GFDL or CC-BY-SA-3.0], via Wikimedia Commons
Eventually, about mid spring, the larvae are ready to pupate. Still enmasse, they make their way into the ground, burrow in several centimetres, and make themselves a strong paper-like cocoon. It might take two or three years before the adult emerges.
I intended to take fresh photos today, but the bunch had moved up the branch overnight (featured photo). I think they are fascinating, and it will be interesting to see if they do survive to pupate. Small groups of twenty or so do not always survive. A few birds, currawongs and cuckoo-shrikes will eat them. Good luck to them!
Currawong
By D. Gordon E. Robertson (Own work) [CC-BY-SA-3.0 or GFDL], via Wikimedia Commons
Unbelievable. The creatures you have in Australia are jaw dropping. Thanks for expanding in this most unusual one.
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Icky is right. Wonder what their purpose is other than bird food.
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They are made for the wonderment of little kids! 😀
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… and big kids, too! 🙂
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Thanks for investigating these wonders. I have had them in trees, but really didn’t know the full cycle. Fascinating, thanks Christine! ❤
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I have been subscribed to your blog for ages but haven’t seen any posts. The problem might be that I don’t bother with the Reader but count on WP archives and email to catch up. Just signed up for e-mail notifications.
Thanks so much for the heads up this morning. I do appreciate a sharp eye.
This post is interesting but, I agree, ick…UG-l-y too. 😦 Good post, though.
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Hi Tess, you’re welcome. Thanks for following me for so long, appreciated. I hadn’t commented on your blog in an age so I’m easily missed, and I’m way behind on your terrific China trip posts. I’ve promised myself to catch up with them over the weekend. I wandered over to your blog yesterday after looking at the rules for the 99 word flash fiction, from the reader initially. Thanks for dropping by, Tess 🙂
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They’re still “eeeewwwww” inducing, but learning of their life cycle and living is fascinating. I’m glad to read this follow up post. 🙂
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I’m glad about that, Cindi. Thanks. ❤
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I couldn’t see the larvae in the tree this morning. Perhaps they have ventured into the ground overnight, else a flock of birds took them. I didn’t want to traipse around in the frontyard to see around the base of the tree. 🙂
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We had lots of spitfires in the trees at the back of our house in Perth when I was just a wee girl — very nasty things to get too close to! Thank you very much for the additional background info 🙂
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Everyone seems to remember them, or have them about. Thanks for dropping by my blog Paula, much appreciated. 🙂
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