Uropygid Sexing?

[Mr. Mordax]

So, I just got a juvenile Uropygid (I think it's Mastigoproctus giganteus), and I was wondering how to sex it. I searched the boards for a while, but most of the sexing posts are so old that the pics are no longer up.

Any help is greatly appreciated.

 

[Jonathan]

.

Hi,
I read about this in the latest Elytra and Antenna magazine tonight. Something about males first ventral abdominal segment is pointed, and overlaps to the second, and sometimes third segment. I have never seen one, so I hope that little bit helps.
Jon

 

[Nikos]

Check this thread:
http://www.arachnoboards.com/ab/showthread.php?t=80994

Lots of info in there.

Btw in case any mods read this, I think the above mentioned thread deserves to be sticky since it contains lots of info about Uropygids

 

[Mr. Mordax]

I had seen that post, but I didn't notice the difference until Jonathan mentioned it just now (the other places I'd read it, no one specified ventral). I guess I have to look closer now since it's pretty small and my one ventral picture didn't show enough.

Here's pictures in case anyone's interested. By the way, is that roach too big for it? Or should I even worry about feeding if it's abdomen is that huge?

 

[Jeremy Huff]

Looks like you have a third stage juvenile M. giganteus. It will be mature in the 5th stage (about two years from now). It should burrow down for the winter and moult in early spring before returning to the surface. You should give it a deep sandy substrate that is a little damp with burried bark so it can dig out a chamber underneath it. Once it is down and plugged the hole, you won't need to feed it for the duration of it being underground.

As for sexing...it shows female characteristics in the pedipalps tarsal apophosis but it would need to be dissected to confirm...You will just need to wait...

hope this helps
Jeremy

 

[Mr. Mordax]

Thanks! I got a look at the underside last night and compared it to the post someone mentioned . . . early results are inconclusive at best. :?

Maybe I have to wait for it to be mature before I can sex it accurately? Anywho, thanks for all the advice!

 

[Ganoderma]

I dont know about sexing it, but that is one fat individual. i would lay off feeding for a bit personally....looks like it may explode!

 

[Mr. Mordax]

Ok. I'll remove the roach for the time being.

Kind of weird, that the guy who gave it to me said it wasn't being a very good feeder. I wonder how long he had it.

 

[P.jasonius]

I've heard (from a breeder) they stay pretty fat even when they haven't been fed for a while.

 

[Ganoderma]

they can get very skinny. but that is really very fat!

 

[Jeremy Huff]

This one looks like it should be set up in an overwintering enclosure. It won't need to feed again until the spring. The best set-up I have found for M. giganteus is gallon plastic jars. I angla a piece of bark to the the bottom and fill with a 80% sand/20% peat mix. The peat I add has been soaked and squeezed. The sand I keep damp. The whipscorpion will dig out a chamber that it bill plug. I have always been able to keep an eye on them in these jars because they make the chamber at the bottom and you can view them all winter. They will moult in this chamber and give birth if bred. After moulting or after the new babies have their first moult, they will emerge and feed.

Jeremy

 

[Mr. Mordax]

Ok! Thanks for all the info! I'll deepen the strate and leave it alone.

 

[Mr. Mordax]

Bit of an update, if anyone's still reading:

I gave it deeper substrate and cave-encouragement with a piece of cork bark. It made itself a nice little hole with two tunnels reaching up to the surface (so maybe it's not ready to molt just yet?).

I know Jeremy said it won't need feeding again 'till spring, but I saw it sitting by the tankside tunnel while in the cave looking almost like it was waiting for prey. I got a roach to walk down the tunnel and the Uropygid snatched it up almost instantly. I tried again a week later and got to watch it use its feeler-legs to herd the roach to its pedipalps.

These are fun creatures!

So thanks once more for all the tips everyone; it seems to be doing real well.