X. immanis molted -- help sexing, please

astraldisaster

Arachnobaron
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Mar 5, 2011
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Managed to catch my Xenesthis immanis sling at the tail end of its molt:











Looks like it's starting to show some colors! It's still very young (the molt measures a very leggy 2.5" diagonally), but I was hoping to sex it if it isn't too soon. Anyone care to take a look here or here and let me know what you think?

Looks female to me, though I'm not 100% sure that flap is a spermatheca. It's barely visible with the naked eye...until I looked at these photos, I assumed I had a male.

Sorry to post this request here, by the way, but I got no comments on my gallery photos and I'd really like some opinions. Thanks in advance.
 
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Hobo

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Maybe try and stretch out the molt in the abdomen area and take another more straight on shot?
Given it's color, it seems to me like it's just a fold of abdomen skin. Usually it should be clear, and have almost no color, especially with one so small.

Also, these have lobed spermathecae, it wouldn't be just a broad flap, unless we are looking at the uterus externus.
 

astraldisaster

Arachnobaron
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Alright, thanks. I was thinking the flap might just be a wrinkle...in which case, I probably have a male...? Unfortunately, the exuvia's totally crispy by now so I'm not sure I could stretch it out. Do you think it's worth soaking it in soapy water? I did get some more straight-on shots, but all of them are out of focus. (Frankly, I'm amazed my ancient point & shoot camera was even able to take these.)

Maybe I'll just have to wait until the next molt.
 

Hobo

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Here's what I do. I've rehydrated molts months old using this.

Get yourself some kind of airtight container. A delicup, or food container works best.
Then, take paper towels, and soak them if HOT soap water. Get it so it's wet, but nothing drips out if you hold it up.
Pack it down at the bottom of your container, put the skin in there, and close the lid. It should get real steamy.
Wait about an hour, sometimes less, and check it's pliability.
When you are satisfied, take it out and very carefully stretch it out.
If the abdomen is still brittle, you can dab it with the soapy paper towels, maybe squeezing a drop in, and immediately wicking up extra moisture with a dry paper towel.

I don't soak for a number of reasons.
When wet, a lot of the features will be distorted and hard to see with the reflection of moisture.
Also, particularly with young ones, the possiblly present spermathecae and uterus externus will stick to the exuvium, becoming almost invisible since they are still clear.
When wet, the exuvium is very easily torn when trying to stretch it out.

When done improperly, the spermathecae can be easily missed with one so small, so I would still call your spider unsexed until you can get better shots, and perhaps when the spider is larger.
 

astraldisaster

Arachnobaron
Old Timer
Joined
Mar 5, 2011
Messages
311
I'll give that a shot, thanks! I wish I had some better tools for stretching the molt out once it softens, but I'm stuck with (regular drug store) tweezers and Q-Tips.
 
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