For many years I have been intrigued by holes in my hillside near Cooran in the Mary Valley. The holes are quite deep, and in amongst phyllite in very dry, rocky country. Indeed, my place has been described as a ‘dry, hungry ridge’!
The holes are fairly common, and a very long way from my dam, and further still to the creek (Coles Creek which flows into the Mary River). They often have a white material near the top of the hole, like
kaolin, a clay like substance. My interest (obsession?) was sparked, and I wanted to find out what made these, and who lived here? It was not until I was out looking around in very heavy rain that I saw two
long feelers sticking up out of the now completely saturated hole. They quickly disappeared back down the hole.

Ok, it looked like a crayfish…but I have only ever seen crayfish in creeks and dams, not on a dry, hungry ridge, so what gives? Continued attempts to get a good photo failed, however I did get an average shot which I sent to the Queensland Museum. What a great service the Museum offers for interested people like me! By this time I had asked around, and learnt of a rather interesting crayfish
called the Inland Yabby. I wondered if this was it.

The reply came back from the Museum:- “It seems that nothing much has been specifically done on Cherax punctatus, and indeed there may be some identity issues with that species (as indicated in the link)”.

Ok, good, progress.

Above and below, yabby holes.
The mystery solved, Cherax punctatus,
complete with flatworms!
I am lucky to work in natural resource management, and so dug a bit deeper with colleagues, one of which is Paul Donatiu from Healthy Land and Water… who happens to have a mate who is with the Australian Crayfish Project (ACP).

In a following deluge, I was finally able to get a good photo, and even a short video. I sent the photo to Paul, who sent it to Rob McCormick from ACP.

And woo hoo, I finally had a win.

“yes that’s a Cherax punctatus. A cryptic species so photos are rare.” “Cherax punctatus will use streams but are not usually a stream crayfish. They have been referred to as a terrestrial crayfish…”

What a fascinating animal, one I have been privileged to meet. And they happen to live on a Nature Refuge, so their habitat is secure too.

But wait, there is more!

I sent the photo to Dr Ian Gynther, a friend and colleague. Ian likes interesting stuff, so was happy to have a look. Ian’s trained eye picked up something that I did not. I thought the photo was good, as it showed the ‘hairs’ under the body of the crayfish…not so! From Ian…

“In my haste last week, I didn’t notice the extra detail in your wonderful photo of the delightful crayfish. Check out the critters I’ve pointed out with red arrows in the attached version of one of your photos. These are commensal flatworms that live on the cray. They go by the genus name of Temnocephala. When the cray is out of the water, the flatworms just appear like amorphous blobs and are hardly noticeable. When the cray is submerged, the flatworms extend their long, thin tentacles from the head end and look a bit like a Hydra.

Cool, eh? I’ve never fully understood the true nature of the commensal relationship, i.e.
what each party gets out of the hitchhiking arrangement.”

Article and photos by Phil Moran
Land for Wildlife member
Cooran, Sunshine Coast
Manager, Noosa & District Landcare


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