It was over a year ago that I first saw this flying insect that had caught a large spider and was dragging it off somewhere presumably to eat. I’d never seen anything like it and I spent a while researching to try and work out what it was. At the time I thought it was a robber fly but now I think it’s a spider wasp!
Robber flys do indeed prey on some spiders and other insects but the images really dont look anything like what I’d seen.
The spider wasp is a much closer match. I’ve seen a few now, here’s some pictures of a smaller spider wasp with another decent sized spider. This particular one was struggling a bit with it’s prey. It even tried to fly a bit and only just managed it. Looking at the picture the spider could easily weigh more than the wasp!
Spider wasps are known to chop off the legs of the spider to make it easier to carry. All the ones I’ve seen the spiders are missing their legs. Nature is brutal!
[update] – When I wrote this I thought the creature was a robber fly, now I think it’s a spider wasp.
Here’s something you don’t see every day, a large fly like creature walking along carrying a sizeable spider underneath it! Now that’s a prey reversal! A bit like seeing a huge rat hauling a dead cat somewhere.
The fly was black, about 4cm in length with long legs that allowed it to carry the spider underneath it and still walk easily. The one I saw was on a mission to get somewhere, it walked quickly over the pavement for about 4m and then climbed a wall before I lost it. It had wings but didn’t try to fly, maybe the spider was too heavy for it. The spider was slightly longer than the fly and looked bulkier, all the spiders legs were gone and it was being carried inverted with it’s abdomen towards the front of the fly.
Curious as to if this was normal I did some searching. The closest thing I could find that lives in the area is a robber fly. “Robber flies are large, bristly flies that catch their prey (usually other insects) mid-flight.” Robber flys are known to catch and eat spiders, the fly I saw didn’t have the same enlarged powerful chest as the robber fly photos on the articles. It looks like there is some variation between robber fly species so maybe it’s just a different species that I saw.
It was moving fast and I only had my phone on me so I found it hard to get a clear picture, but you can see the size of the spider compared to a garden hose and a house brick. The spider looked like a huntsman, I’m not sure how the fly would have killed it and removed it’s legs, or maybe it found the spider like that?
I was working in the yard when Jess called me over to see a beetle she’d found. I was a bit reluctant to stop work but she convinced me “c’mon dad, you’ll love it!” She was right. With a quick search this beetle was simple to identify as a Fiddler Beetle.
Fiddler Beetles are native to Australia, they are found all the way up and down the east coast. The first thing you notice about them is their appearance, they are black with a striking pattern of yellow or green markings that look like they have been applied as part of a carefully thought out tribal design. The one Jess found had green markings. Not sure if it was male or female, often in nature the males are more visually striking than the ladies but I couldn’t find any sources that distinguished between the two in appearance. Fiddler beetles live in heathland, eucalypt forest and suburban parks and yards. They lay their eggs in rotting logs or damp soil. After hatching the grubs eat wood until they are ready to emerge as adult beetles in the early summer.
It took 4 years for me to finally work out what my “Unknown Bug” is! Finding the Cotton Harlequin Bug was what lead me to it. I recognized that they look quite similar in structure and shape. This gave me some more terms to search for ( shield bug ) and I finally got a match!
So it’s with belated pride I’d like to introduce to you, the “Gum Tree Shield Bug” otherwise known as a “Stink Bug”!
The bugs that I found appear to be in the nymph stage. The nymphs spend most of their time under the bark while the adults roam about on the outside of the tree and are better camouflaged. The patterns on the nymphs is captivating, it looks like an Aboriginal painting come to life.
Gum Tree Shield Bugs are found all over Australia in open forests or woodlands. They get their Stink Bug label from their ability to secrete a smelly corrosive substance as a defence against predators. Glad I avoided that.