Genus Cyriocosmus

[tarcan]

Martin, is this "mutant" from the batch of 1/6" (tobago) s'lings you are selling right now?

No, the ones for sale are from a different eggsac...

Nice girl that you have there Niklas, congrats

Martin

 

[MindUtopia]

What's the trick to sexing these guys other than just having a really high powered maginifier? Any particular distinguishing characteristics I should be looking for either on an exuvium or ventrally? And at what size does it usually become possible to sex females? I have 5 of these guys ranging from 1/4" to 1/2" and I'm not even sure where to start with something this tiny!

 

[Lorgakor]

I'm wondering the same thing MindUtopia! They are so small, I just don't know how I'm going to sex mine. Mine is 1" now. I'm wondering at what size males usually mature. At least then I'll know if it passes that size it will be female!

 

[tarcan]

I sex them with the molt and the microscope. At 1" legspan, the spermatheca is extremely well developped, it is easy to spot because it has such a unique shape (for lack of finding proper comparison in english, it is shaped a bit like a pig tail or a cork screw). The only tricky thing might be to properly unfold the part of the abdomen to view the area. I use thin needles to do that and do it under the microscope.

Watch out for the "it is quite big it must be a female" technique, because you could be really surprised. Mature males vary a bit in size. My first one ever was tiny and I believed they would all be that size. I thought I had loads of females... was surprised to find several other males later on in time

Martin

 

[tarcan]

Laura, if you got it's last molt and want to send it over, I can have a look if you wish.

 

[Lorgakor]

Hi Martin,
The moult is still in the burrow, I could retreive it but it would be very dried out. Would you still be able to work with it?
Otherwise I'm pretty patient, I could wait until it moults again and send you that one.
Thanks for the offer!
Cheers,
Laura

 

[tarcan]

Laura,

even if it is complet.y dry it is not a problem. Water with dish washing soap works miracles!

Martin

 

[Arachnophilist]

ooh how does the water with soap work?? i would like to know how to revive some of mine if possible. i heard oil works but it just made them all mush..

 

[tarcan]

well, I just use it to soften the molt and once I have sexed the animal, I throw it away! If you soak it with that and dry it, it will not be really pretty afterwards, so maybe not that good for what you want to do (I presume just place the molt in a nice position and keep it?).

 

[moricollins]

Watch out for the "it is quite big it must be a female" technique, because you could be really surprised. Mature males vary a bit in size. My first one ever was tiny and I believed they would all be that size. I thought I had loads of females... was surprised to find several other males later on in time

Martin

My two mature males were quite large in comparison to what I was expecting, and to the size of some of the females martin has produced sacks with I believe..... could always be wrong.

 

[tarcan]

Was board tonight and dug up some old pictures that I think I never posted...

Comparison shot between a 1st instar and a 2nd instar...

And C. elegans female, dorsal and ventral view

Martin

 

[MindUtopia]

Martin,

In the earlier pic comparing the C. elegans and the sp. Bolivia males? What's the scale? How big were each in that pic?

 

[tarcan]

yes, now that I realise the picture only makes sense if you have already seen a mature male C. elegans.

Here is a pic of one with measurement. Then you can guess for the other species.

Martin

 

[Tescos]

I sex them with the molt and the microscope. At 1" legspan, the spermatheca is extremely well developped, it is easy to spot because it has such a unique shape (for lack of finding proper comparison in english, it is shaped a bit like a pig tail or a cork screw). The only tricky thing might be to properly unfold the part of the abdomen to view the area. I use thin needles to do that and do it under the microscope.

Watch out for the "it is quite big it must be a female" technique, because you could be really surprised. Mature males vary a bit in size. My first one ever was tiny and I believed they would all be that size. I thought I had loads of females... was surprised to find several other males later on in time

Martin

Hi Martin

Here is a pic of those `pig tails´for you.
Cyriocosmus elegans spermatheca
The largest male I had was 4cm leg span. Have you seen larger?
Oh and don't forget that your adding another elegans to your group when you come over to KWH so get the larger of your terrariums ready.

All the best
Chris

 

[Taceas]

I find these little guys to be quite fascinating. But I have one and I'm sure its extremely basic and dumb question...how can these be considered Theraphosid when we have native spiders that are much larger. What is the requirement to be considered a "tarantula", if size clearly isn't it.

I really love the pronounced shiny patch on their rumps, they are very unique looking...

 

[Arachnophilist]

It is because of the family of spiders they belong to and where on the evolutionary scale they fit in.. Theraphosids are one of 15 major families of tarantula. they are primitive spiders. if you have more questions PM me.

 

[tarcan]

Hi Martin

Here is a pic of those `pig tails´for you.
Cyriocosmus elegans spermatheca
The largest male I had was 4cm leg span. Have you seen larger?
Oh and don't forget that your adding another elegans to your group when you come over to KWH so get the larger of your terrariums ready.

All the best
Chris

Chris,

This pretty as big as I ever saw any. Thanks for the picture link...

I had forgotten about that one, I have a 55 gallon tank ready for her! LOL

See you in a few weeks

Martin

 

[tarcan]

Here is a little guy who will grow up to be a cutie... right now a bit too small to show any kind of distinguising pattern...

spiderling of Cyriocosmus sp. "leetzi" Venezuela

Martin

 

[becca81]

Cyriocosmus sp. "Bolivia"

 

[MindUtopia]

A not so terrific shot of one of my 5 C. elegans