Parasites and Trapezites: Strange and rare insects at Daisy Hill

I had a great day searching for insects in Daisy Hill Conservation Park today. I found some rare and unusual critters too. The most visually spectacular of them all was a beetle from the Rhipiphoridae family, which are also known as wedge-shaped beetles. The one I found was a male, as told by his extravagant antennae, and he was perched at the tip of a small wattle. Rhipiphorids have a surprising lifecycle for a beetle, with their grubs being internal parasitoids of other insects, including other beetles.

The strangest of all the insects I found was actually one that found me! I was standing at the track edge on the Buhot Creek Circuit examining something that I can’t quite remember now, when I felt a fly land on my leg. When I looked down, I saw a fly like no other I had seen before. It had a flattened shape with a strange, hawk-like face, complete with hooked mouthparts, and I didn’t trust its intentions! I tried to shake it off, but it kept landing back on my leg repeatedly, and I realised I should probably try and get a photo of such a strange creature anyway. 

I had a feeling it was a bird fly, a creature I’d seen mentioned in the Queensland Museum’s 'Wildlife of Greater Brisbane' which sucks the blood of large birds like kookaburras and currawongs. Further research at home proved my ID correct, and the fly was indeed a member of the Hippoboscidae family of louse flies, probably Ornithomya fuscipennis as mentioned in ‘Wildlife…’. 

Hippoboscids are bizarre flies to say the least; some members of the group are flightless and live as external parasites on mammals like bats, wallabies and sheep, while flying members of the group choose birds as hosts. Instead of laying eggs, Hippoboscid offspring develop one at a time inside their mother, and she essentially gives birth to a pupa, because it’s the adult fly rather than a maggot that emerges from the casing. For Ornithomya species, this would all occur inside a bird’s nest. 

While taking photos of the strange but fascinating critter that had landed on me, I noticed it made no attempt to bite me, and later learned that louse flies are obligate parasites, which means they can only live on the one type of host. Because the bird-targetting species can fly, and can therefore move from individual host to host, they are a vector for spreading disease in avian populations.

The last insect I want to write about is neither spectacular, nor all that fascinating, but it does seem to be rarely observed in South-east Queensland. It was a medium-to-large-sized skipper that I observed twice in the forest at Daisy Hill, which turned out to be Trapezites phigalia, also known as the heath ochre.

This small butterfly has a lifecycle based around Lomandra plants, of which there are an abundance of multiple species along Buhot Creek. There are no iNaturalist records for this species in Queensland, and the nearest Atlas of Living Australia record is from North Stradbroke Island. The two individuals I saw were both presumably male, as they were perched in classic skipper territorial pose, on or beside the track.