Land Crabs?

[hornet]

i have looked into them and i think these would be good candidates for captive breeding because unlike other "freshwater crabs" and land crabs they carry their larvae under them insted of the larvae becoming plankton in brackish/marine environments.

 

[PhilK]

How did you find that info, mate? If you could swing any info my way I'd appreciate it, because I don't want to kill them when I get them.

These guys will go on freshwater then? ..they don't need salt/brackish?

 

[nightowl]

We also have some of these crabs in stock now (thanks bylo) at Xotic Pet Supplies and I must say they seem to be inquisitive creatures! I have them in a tank with gravel (aquarium) substrate and a large water dish at one end. They use the water to hide in and are very responsive to movement. Cool little guys!

 

[bwana]

Hi,
These crabs are also found from ravenshoe/millstream area. No salt water here.
Once whilst out herping with a friend ,I asked had he seen anything and he casually remarked "Oh just a few crabs."
I had no idea that freshwater crabs even exisited and asked him to show me them.
I keep a few in my turtle tanks and still have some of the larger ones 3 years later.
They are an excellent aquarium inhabitant and dont harrass the turtles.

 

[PhilK]

Do they drown in water? I know some land crabs are totally land crabs and will drown if put in water over their head for too long...

When I keep them, I'll have 3/4 coco peat mixed with sand and 1/4 of the tank partioned off with creek sand and water with some driftwood. Figure they can go into the water when they want, and be on land when they want. Would this suit them?

I've gne only 1/4 water because I heard they're mostly land based..

 

[nightowl]

Not sure if they drown, it is the first place they head when (I assume) they feel threatened.

I used aquarium gravel to simulate a dry creek bed, but am going to add some sand and wood as well. Atleast if you supply a water reservoire they can choose whether they want to be in the water or not. I added some rocks to the water bowl to give them something to grip and get out if needed. maybe a false bottom system like bylo uses for the desert scorps might work? A layer of gravel at the base with a tube going from the base to the top to add water to the gravel and let the humidity rise through the sand substrate above?

 

[PhilK]

I thought they didn't need much humidity as they're from an arid zone?

 

[nightowl]

depends if they burrow? In nature the soil/substrate is damp under the surface (especially creek beds) so IMO a false bottom system may work? The sand and gravel will stay dry on top but as the crab burrows it will get more humid.

 

[PhilK]

Does anyone know if they do burrow?

 

[bylo]

depends if they burrow? In nature the soil/substrate is damp under the surface (especially creek beds) so IMO a false bottom system may work? The sand and gravel will stay dry on top but as the crab burrows it will get more humid.

you have a good point there , as they do burrow to escape the dry .

yes some sort of false bottom would be an idea , i might start thinking of a design myself .

 

[PhilK]

Hmmm a false bottom set-up...
What type of gravel do you use for that? Fairly large gravel?

The only problem is that crabs are crazy good climbers, so they could climb the tube and away to freedom!

 

[bylo]

i wouldn't use a tube as i am not thinking of using sand only the gravel so just pour the water through the stones .

i am experimenting at the moment

 

[PhilK]

I will be keeping them on probably 75% sand 25% cocopeat, and I'll have the false bottom under that I guess.
Then for the water it'll be 6mm river gravel and some finer sand with some driftwood.

 

[bylo]

that sounds good , and a few fake plants to get a splash of colour through out the tank

 

[Inkslinger]

Here is a little more info:

All fresh water crabs

Taxonomic Checklist: Species
Austrothelphusa agassizi Rathburn
Austrothelphusa angustifrons Milne Edwards
Austrothelphusa raceki Bishop
Austrothelphusa tigrina Short
Austrothelphusa transversa Martens
Austrothelphusa valentula Riek
Austrothelphusa wasselli Bishop

Major Group: Crustacea
Minor Group: Malacostraca
Order: Decapoda
Family: Parathelphusidae (formerly Sundathelphusidae)
Genus: Austrothelphusa (formerly Holthuisana)
This family is represented in Australia by a single genus, Austrohelphusa Bott.

Descriptive Features:
carapace subovate to quadrilateral, occasionally quadrate, usually wider than long, dorsal surface usually smooth, rarely setose
carapace regions more or less distinct, branchial regions often noticeably swollen, gastro-cardiac groove distinct
epigastric and postorbital cristae sharp to almost absent
front usually entire, often with median triangle well defined or discernible
antero- and posterolateral margins well demarcated, anterolateral margin usually prominently convex, margin usually with at least one tooth (epibranchial), rarely obsolescent, often with 2-3 teeth (excluding external orbital tooth), rarely appearing serrate
3rd maxillipeds completely closing buccal cavity
mandibular palp 3-segmented, terminal segment clearly bilobed, although one lobe slightly smaller than other
male and female abdomens with 7 free segments, male abdomen subtriangular to distinctly T-shaped with last 3-4 segments very narrow
terminal segment always simple or may appear dilated, never with prominent spines, setae and/or processes
2nd gonopod relatively short, rarely longer than ½ of 1st gonopod
Carapace width: up to 50 mm

Distribution: NSW, NT, Qld, SA, WA
Sensitivity Rating: SIGNAL grade 3 (as Sundathelphusidae)
AUSRIVAS Taxacode: OX519999 (as Sundathelphusidae)
Functional Feeding Group: gathering collectors




Ecology: Austrothelphusa decapods occur in rivers, creeks, waterholes, springs, swamps and temporary ponds. Most species occur only in Queensland, but Austrothelphusa transversa is widespread. Adults burrow up to 1m in swampy ground or into the stream banks. They can survive several years of drought by plugging their burrows with clay.
These crabs are omnivores.
Parathelphusids do not have a planktonic larval stage; young miniature crabs hatch from large eggs and are carried around by the female for several days.
Information Sources: Davie 2002b, Williams 1980, Hawking & Smith 1997
Key to Species: Horwitz 1995

Interesting to note they are note found in Victoria

 

[bylo]

Thanks inkslinger.

was there any pictures to identify the species down to one name .
or any info to lead us to the exact species name .

cheers

 

[Inkslinger]

not Holthuisana, not transversa still reasearching not a lot of reliable info

f you want a professional opinion, Dr Gary Poore at the Museum of Victoria (Melbourne Museum campus)

 

[PhilK]

You soudn really knowledgable ink.. are you studying them or something?
From what you know, what do you think of my setup idea? Would it be OK for them?

 

[Inkslinger]

Been on this earth a long time PhilK love critters of all kinds especially bugs and reptiles, If I am not on the Pc or at work I read.
ATM I have been off work quite ill and looking into the crabs have given me something to do. I am actually thinking of getting a few my self, as to set up I always where possible try to replicate where they come from.
Their natural habitat. Nowadays with the Internet that makes it pretty easy.

Although the search for info on the crabs is not so easy but I will keep looking.

 

[bylo]

apparently there is a book on inland aquatic inverts by Williams , i am trying to find more info on the book so i can buy it .

if you guys have time can you try to track it down for me aswell

cheers