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Hitch-hikers on yabbies/crayfish


fishmosy

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I've always loved freshwater crayfish or yabbies since first catching them and keeping them in aquaria as a kid. Back then I thought the brown things crawling on them (called temnocephalans or flatworms) were parasites. I learnt in my teens that these are actually not parasites, but just use the yabbies as a place to live.

Anyway I came across this article today that reminded me about these cool creatures.

http://theconversation.com/flatworms-that-live-on-crayfish-are-adorable-in-their-own-right-20608

Definitely worth checking out if you are a fan of crays.

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  • 8 months later...
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As a kid I used to catch Euastacus sp with these on board as well. I miss keeping crays, damn awareness of the law!

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I hve always wanted a really big tank t o have some blue marron :(

Know the feeling Oz I got offered a pair from a fish farm in WA and had to say NO because they are illegal in Vic.

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I sincerely hope they aren't here and nobody tries to sneak them in. The American species (specifically including Procambarus clarkii) are resistant carriers of the "Crayfish disease" which nearly wiped out freshwater crayfish in Europe when it arrived there. 

Here in Australia we have the most diverse and interesting freshwater crayfish fauna on earth, including some dwarf crays that have more potential for line-breeding colour forms (purple, black, blue, red etc) than wild P. clarkii ever did. Our crays have been confirmed to also be highly susceptible to the disease - it is possible that our amazing native freshwater crabs and shrimp are equally as susceptible. Fear of this disease impacting the economically important crustacean industry is why no exotic shrimp have been approved for legal importation here and probably none ever will be. If you think the authorities are tough on the shrimp hobby now, wait and see how they are if the New World crays start to show up. Don't expect there to be a hobby surviving here for very long. 

I would be in full support of any tank of Procambarus in Australia to be nuked by fisheries. Don't tell me if you've got them. 

 

 

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Thanks. Always good to learn new things. If indeed there is a huge risk to our fauna, then I agree they should not be in the country. I first got to know about them from an article in TFH magazine. So I ask Mr Google and search on most Australian fish/shrimp forums. Apparently someone spotted a pair selling in an LFS a few years ago. One of them died before they bred. Not sure what becomes of the other. That's about all that I've heard of them.

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You and I both inverted! G. insolitus is down here and I've seen them but lacus is nicer. I think they're both protected though. They aren't the species I was referring to; the Gramastacus are smaller but the mini Cherax are more colourful. There has to be a way to legally get some dwarf spinys into captive culture! 

@jc12, I went off about it to make a point that readers will hopefully remember.  There IS a real risk not only to our native fauna but to our entire hobby. These foreign crays are THE thing that will bring the authorities crashing down on the hobby... we don't need blanket bans placed on all exotic crustaceans as a kneejerk reaction to these crays arriving here. So far we aren't called criminals just for keeping shrimp. I want to keep keeping them and the shops want to keep selling them.  I highly recommend that if anyone out there does have these mexicrays - keep a tight, heavy lid on it. Tight, heavy lid. Certainly don't distribute any. Probably just destroy them, accept the loss, move on. 

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