Australian freshwater crabs - Austrothelphusa?

[Callatya]

Has anyone here kept any crabs from this genus? I believe that all but one are Australian natives, so I'm not liking my chances. Sadly, they aren't all that common with Aussie aquarists. In 7 years I've met one person who kept them. I guess they mostly get sold to the goldfish crowd. They come in waves to my area, usually about 2-3 shipments per year, and the sales rates seem a bit hit and miss.

Anyway, any info you have would be fantastic

I have what I believe is a male. Not fully grown yet, and quite a character when you warm him up (pathetic amount of information about them in aquaria, I'm basing my whole keeping strategy around the rainbowfish that are found in the same area, so fingers crossed!)

I'm guessing either omnivorous or detrivorus? He quite likes blackworms and spent a lot of yesterday stuffing java moss into his mouth. Can't be the most tasty treat, but he is choosing it over spirulina wafers so maybe I'll have to start with veggies or some other aquatic plant to tempt him. Those mouth parts are fascinating! it is like two little window shutters banging around!

He doesn't seem to be a burrower or a climber, more of a scuttler, and is really not all that interested in climbing but does spend some time out of his day with his 'nose' out of the water. He can get fully out, but so far he hasn't.

This is Marshall. Austrothelphusa agassizi

[James26aus]

I have kept a crab which I believe to be of the same species as your own; mine was a female so it didn't have the larger claw. Judging from the photos, yours looks a lot healthier than mine ever did.



When it was purchased the salesperson assured me it would be happy with a fully aquatic lifestyle - this proved incorrect. When I provided my crab with land access it made use of it every night, digging around in the sand, etc. Only lived for about 4 months, which it shames me to admit, although it may have been diseased from the beginning.

I think they are fully freshwater. I put a bit of salt in which may have been the cause of death, more of an accident really when treating some unusual parasites (I was wiping them off with a cotton-bud dipped in salt water). My crab had also lost an eye prior to this, I'm not sure if it was because of the parasites or something else.

As far as feeding goes, they seem to enjoy algae/vegetation. Mine cleaned up a lot of hair algae that was growing on some Java Moss, I fed her various vegetables too.

I asked about them today at a pet store, the guy referred to them as 'Strawberry Crabs' but googling the name didn't provide any helpful information. If you discover anything else about caring for these crabs, please let me know - I'd love to try keeping them again.

[Callatya]

That is the one! Gosh, the colour range on these is incredible. I spotted a few last week that were very nearly almost white where these are red/pink. Not sure if it relates to health, diet or environment, but it is definitely interesting.

They are on the wholesale list as "freshwater crabs" or "NT freshwater crabs". I've heard them called brown backed crabs. Strawberry crabs is new to me, but it does sound more saleable than all the others!

I fully agree with the vegetitation thing. So far Marshall's favourite hobby is eating me out of house and duckweed, which is no mean feat! He perches on his heater (preferred out-of-water possie, even though there are others available) and just shovels it in. He makes mighty short work of Java moss. On the plus side, nothing ever gets a chance to die and rot, it all gets eaten too quickly. He does still like his meaty foods (he grabs the end of my feeding dropper, shoves it in his mouth and starts chewing as I empty the contents in! It is fascinating!), but I'm thinking he is just an opportunistic carnivore.
I'm feeding one day, and giving him 2 days off, it seems to be working pretty well.

Water quality seems to be less of an issue than I'd expected. Fully cycled is a must, but because of the drought and then rain, I've held off on WCs for a few months (the ones that I did change either turned a lovely shade of green or mysteriously killed everything:() and he's doing fine. I'm sure he'd prefer a change, but he's not getting anything but small partials with spring water until I'm certain it is safe. I'm hesitant to admit it, but I'm not running a filter on his tank at the moment. The water movement seemed to upset him, and the tank is stable enough without, so I'm just doing regular substrate cleaning.

He is in with two male gambusia, but he seems to ignore them, even with his heater turned on (most times when I've heated yabbies a little over winter, they've gone super-hunter on me) which leads me to believe that his temperature tolerance is pretty high. He'll sit quite happily at anywhere between 21*C and 28*C, although he does seem to show increased activity around 27*, so I keep him just under.

Currently he is on my kitchen bench with no heater either, as I've had to shift him to avoid paint fumes. I thought he's sulk in the cold, but he seems a lot more active than when I first got him and had him unheated, so perhaps it is partially health related? Maybe he needed some food in his belly and a bit of TLC? Not sure. He'll be getting larger quarters and his heater back very shortly, so it'll be interesting to see what changes.

He hasn't moulted get, I'm not even sure what crabs do to moult Something like yabbies I guess?

I've been contemplating getting a female too, but I've yet to sort out how territories work, and a friend of mine who got a female shortly before I got Marshall has just had her die for unknown reasons. I'm thinking that perhaps the cold temperatures played a part, but it does have me a little worried as I'm hesitant to risk this boy.

Please pop back and update if you give it another go it is nice to have someone to share info with

[PhilK]

Hi there! This is my very first post, and I joined just for this thread basically. Sorry if I drag it up from the depths!

I have been looking for information forever on these crabs, and I finally found some other keepers! I recently bought about 12 off Greg Bylund and I couldn't be happier with them.

This is their tank:




It's 100cm long, 50cm wide and 40cm high. Water portion is 30cm long and 13cm deep including substrate.

I was sold them and was told they are inland freshwater land crabs, and that they enjoy the land but so far they have spent almost all their time in the water side (I may change the land and water sides as a result). Like I said I have about 12 living together, of different sizes. I have found them to be ultimately very omnivorous... They've eaten (in my care) grated carrot, shredded coconut, sultanas, dried fruit, barley, oats, bran and even live crickets fed to them on forceps (very cool to watch). Am hoping they utilise the land part of their enclosure more soon! There is a simple sponge filter in the water side, but the water is still pretty dirty (lots of poo, I assume).

These guys were found in central Qld (or thereabouts) under rocks in a dried out creekbed. Locals say they're very common. They're excellent fun to watch but are pretty scared and jumpy... Unless it's food on the end of forceps!

Hoping they will breed... That would be good.

Some photos of the critters:







Finishing off a delicious cricket.

[Mustafa]

Thanks for your contribution and welcome to the forum! Crabs are some of the most interesting decapods out there actually. Just wanted to give you a heads up that I have removed the URL from your post as posting commercial URLs (links) is not allowed here. Please go to the rules section of the forum and read over the rules if you have not done so already.

Let us know if these guys breed for you. From your description it seems like they would produce fully developed young instead of saltwater larvae.

[PhilK]

Sorry about that!

Yeah apparently when they breed, they carry the eggs with them until they hatch and don't release the young until environmental conditions are just right. At that point they turn into perfect little miniatures of the parents.

This is my understanding.

[Neonshrimp]

Welcome PhilK,

Thanks for your introduction and information about the crab. Great pictures

[Callatya]

Hey Phil! *waves* Nice to find another crab owner!

I think yours might be of the same genus but a different species, the speckling effect is one that I haven't seen in these guys, but I remember seeing it on another type when I was searching. I'll see if I can find the page again...

Your setup seems fantastic! How do you stop sulfur gasses building up under the deeper wet substrate? Is that what the tubing is for? I thought about doing something similar (land/water) but I couldn't think of a way to keep things from becoming manky and smelly. How long has yours been running?

Marshall spends a lot of his time half in/half out of the water, mainly with just his face poking out, He can get fully out of the water, but he doesn't seem to like doing that much, I think he feels too exposed as his main response to being startled or scared is to jump in the water and stay very still.

That is a huge range of foods! they must be loving living with you! I've tried peas, corn, carrot, prawn, rice, caterpillar (cabbage moth) and pumpkin. I hadn't thought of dried fruits, but that is an excellent idea! I'll gave to give those a burl!

If that sand is the river sand stuff you can get at Bunnings, the messy water is probably very fine dirt. I haven't had much problem with poo, but I did have dusty dirty river sand. I washed mine to within an inch of it's life and it was still messy for a few weeks. They could even be tracking dirt into the water from the land part if that wasn't washed. It is fantastic sand though, really suits them (and hides the muck between water changes!)


Looking forward to more updates! I can't believe we've got so many native crab owners in the one place!

[PhilK]

1. How do you stop sulfur gasses building up under the deeper wet substrate? Is that what the tubing is for? I thought about doing something similar (land/water) but I couldn't think of a way to keep things from becoming manky and smelly. How long has yours been running?

2. Marshall spends a lot of his time half in/half out of the water, mainly with just his face poking out


3. If that sand is the river sand stuff you can get at Bunnings, the messy water is probably very fine dirt.

1. The water half of the tank no longer has any sand in it, it's all gravel and is only 'aerated' to stop anaerobes building up by angling the filter output to stir the surface. The tubes are for adding water to the very bottom of the sand, to make the deeper layers wetter in case they want to burrow (which they don't). It doesn't smell and has been running for about 3 weeks.

2. Yeah, mine come to the surface and stick their noses out once in a while. This is because they're obligate air breathers, I figure. They very rarely venture onto the land.

3. Took all the sand out of the water part, and now the water is crystal clear (more or less). The sand is 'medium river' from Centenary Landscape supplies in Brisbane.

[Callatya]

Sounds promising! I'm really interested in how the sand section works out long term as it may provide a housing solution for another species that I'm hoping to get my hands on next year.

I have a hunch they utilise some variant of bimodal respiration because I had a chat to the supplier and they still have crabs doing well in a tank with no surface access 3 months after they first arrived. If they were obligate air breathers (I suspected the same given the behaviour) these should have drowned, and likewise the ones in dry creek beds should have suffocated if they required water. I reckon that breathing surface air might be more efficient though, because that does seem to be the preferred spot. Maybe it is the humidity at that level or the ability to have their bodies supported or gills underwater that makes the half in/half out possie the better choice. No idea really, just thinking out loud. It is times like this a book or profile would be really handy!

Sounds like the same sand. It took me a 2 day soak to loosen the dirt from the sand particles and then about 8 rinses to get it clear. It is just too much water in times like these, so I've started using Sydney white sand which is still amazingly filthy but takes less rinsing to clear up.

[PhilK]

I know what you mean about rinsing stuff! I feel so bad rinsing dirty gravel because of the drought. I just put it in a sieve, and rinse it thoroughly over a bucket and then the bucket goes out onto the garden, so that's at least recycling, right?

After exams I'm going to switch the water and land sides, because they're never on the land (except for one small one, that has made a burrow under a rock). When I switch the water to the big side, I might add a little crayfish or two, maybe some guppies, some javamoss, and some more snails. I'll also hopefully be able to get a small canister filter because the filter I use currently is fairly rubbish.