The Spiderman Crayfish

No doubt you've heard of the spiderman lizard: (The Mwanza flat-headed rock agama Agama mwanzae). But I think this guy deserves the same 'Spiderman' moniker. The red and blue spinycrayfish, Euastacus fleckeri, is endemic to North QLD. Happily for me it's also diurnal, making finding one a relatively easy and hugely fun proposition.


Fifteen species of spiny mountain crayfish have been identified in Queensland, living in cold, fast-flowing streams. In south-east Queensland, suitably cold habitat is found as low as 250m. The further north the crayfish are found, the higher their lower limits, until they are found only above 800m in North Queensland. Each mountain range has its own species of spiny crayfish and genetic samples have confirmed that all have a common ancestor.

It's thought that this ancestral crayfish expanded its range into Queensland over 5,000,000 yrs ago, when temperatures were cooler and rainforest more extensive. With climate change came a contraction and fragmentation of forest habitat, resulting in different mountain top populations separating and evolving into different species. ^


With the temperature and the humidity rising here on the coast it's bliss to slip up a hill and step into cool crisp water. The area, (Mt Lewis), was once a hive of human activity with logging and tin mining being carried out there. Now though, much of it is a national park - complete with the usual shot-up signs and smatterings of rubbish left by 'grown' mummies boys and their wine-cooler princesses ... (no, no - it's alright, we cleaned up after ya's - ya fu....!!!)

Ahem ...

Anyway, it's worth a look if you get the chance. Simply turn right (if you're coming from the coast) at the highlander pub (you can't miss it), and follow your nose. To get to the top it's a good idea to be in a high clearance 4WD, or have ya walkin shoes on - but it's completely up to you.






The very spot


Excuse the amount of particulate in the pics - it's quite difficult to both blunder around in a creek AND get decent shots to share without stirring up a bit of sediment. Patience was definitely the order of the day. Unfortunately the crayfish, (sick of my faffing), clambered out of the water and started heading for the bush!. I intervened, Jo snapped a pic of him in all his indignant glory, moments before I carefully placed him back in his creek - no worse for wear.

I had my pics and he obviously had the hump - so it was time to say goodbye.


A defensive display to warm the heart eh?


A remarkable little beastie and if the boffins are to be believed, one that may well be an indicator species with regard to climate change. If things are indeed getting a bit warmer - that'll eventually spell disaster for the spiderman crayfish. A prospect that I find incredibly depressing ...

But hey, they're not gone yet and where there's life, there's hope eh? ...

So 'till next time, take care - Paul :)


Australasia has over 100 species in a dozen genera. Many of the better-known Australian crayfish are of the genus Cherax, and include the marron (now believed to be two species, Cherax tenuimanus and C. cainii), red-claw crayfish (Cherax quadricarinatus), common yabby (Cherax destructor) and western yabby (Cherax preissii). The marron are some of the largest crayfish in the world. They grow up to several pounds in size. C. tenuimanus is critically endangered, while other large Australasian crayfish are threatened or endangered.

Australia is home to the world's two largest freshwater crayfish – the Tasmanian giant freshwater crayfish Astacopsis gouldi, which can achieve a mass of up to 5 kilograms (11 lb) and is found in the rivers of northern Tasmania, and the Murray crayfish Euastacus armatus, which can reach 2 kilograms (4.4 lb) and is found in much of the southern Murray-Darling basin.

The two species of Paranephrops are endemic to New Zealand, where they are known by the Māori name kōura. ^

Dry In The Wet Tropics

The dry season is getting on my tits. The brown grass, the fine and mildly depressing film of dust covering everything and the endless, bloody amount of Australian rules footy on the T.V have all combined to leave me feeling fractious and prickly ...

Sorry.

Of course, these are luxury problems and it's just that time of year. Funnily enough we've had some absolutely brilliant visitors to the garden over the last while including a juv bandicoot - who reduced me and Jo to floppy gasps and ooohhh's when it bumbled through the other evening. It regarded everything in that strangely cautious yet cavalier way that they have. There is also a young fruit bat who roosts for a time every evening on the same banana plant - like clockwork.

Both very cute.

And would you believe that the sunbirds have done it again? ... Same nest - same drama with the beer fridge - we obviously make good neighbours.

Either that or there's some avian conspiracy to prevent me from having a cold beer ...

... the bastards.

The snakes are also active. Our two resident keelbacks (one yellow - one a pretty speckled grey), have been spied. I even managed a pic of ol'e yeller consuming a cane toad ...

Who's a good snake then eh?


Tropidonophis mairii note the toe of the toad protruding from the corner of the snakes mouth


The other keelback (below) has been no shrinking violet either - we've watched her on a few occasions slipping through the grass (straw) at dusk (keelbacks are predominantly crepuscular), but can be seen at any time. They're the mobile speed camera of reptiles.








As I said, water is precious at the moment and if the juv green tree frog below had the capacity, I've no doubt it would've sighed when it plopped into the only standing body around - the bird bath.


Litoria caerulea


God alone knows what 'Willy' would've done had it still been there in the morning ...


"Willy Wagtail"


Rhipidura leucophrys


The green tree frog wasn't the only amphibian to be found clinging on in less than hospitable conditions - this stoic little graceful tree frog, (below) has claimed a leaf all it's own and seems determined to stay there until the rains come (or the plant dies) - whichever comes first.


Litoria gracilenta


Further afield, Jo and I went for a cruise in the trusty 4b the other weekend - just for fun and to have a look around. We stopped at a creek and had a small cursory explore ... this spider was a bit of a challenge and I ended up a tad soggy, but what a critter ...


Dolomedes facetus


In the creek bed we collected a small amount of alluvial tin that shines a little like silver - but you know ... isn't. Fun all the same ...


Water ... finally!


The waterway was being patrolled by one of my favourite insects - I watched it as it tracked the path of a small tadpole - a throwback to it's youth no doubt ...


More dragonflies (or use the search ^)


And then on a causeway and adjacent creeks we found these ponderously large tadpoles who I think are northern barred frog young - some were well over 100mm in length and it was fantastic to see them in quite large numbers.


Mixophyes schevilli


The Northern Barred Frog inhabits dense tropical rainforest, close to fast-flowing streams. It usually hides and hunts in leaf litter. Like Mixophyes iteratus and Mixophyes fasciolatus, this species lays its eggs on the banks of streams. Rain then washes them into the stream where the tadpoles hatch.

The tadpoles are very large, reaching a length of 12.5 centimetres. The males call from high banks, making a deep "wahk" sound. ^


I hope to get a shot of an adult to share with you in the not too distant future - beautiful frogs that they are.


There's more (there always is eh?), but the weekend sunshine is calling and you've no doubt got better places to be also ... so until next time, take care -
Paul :)


Dolomedes facetus: Hunts beside the water, diving for small fish and insects. Although not the same family as the European Water Spider that builds a bell of air in its underwater web, Dolomedes is quite capable of diving and running across the bottom and remaining there for up to at least one hour. Main prey are fish, tadpoles, aquatic insects including moths and possibly toads, but that has not been confirmed. ^

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