How big should my Xenesthis sp blue female be in order to mate)

Roger Gan

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She just molted a month ago and is around 4.5 inches so what's the proper size for it to mate?
 

l4nsky

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Typically you'll want a female to be about 75% full grown in order to have decent odds at an eggsack, but technically they're mature when the spermatheca becomes darkened and sclerotized. I don't have experience breeding Xenesthis sp, but if I was going to, then 4.5" DLS seems a bit too small to me. I'd probably wait until 5.75" DLS minimum, but I feel like I'd have better odds at 6.25"+ DLS.

Edit: Spelling
 
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heiwut819

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Spermatheca on their ~6" molt are not sclerotized yet, so anything below 6" I wouldn't even bother to try. Depending on how you are measuring it, 4.5" is roughly N6 (DLS fully stretched) or N7 (Legspan not fully stretched) only and not matured.

And even if the spermatheca did sclerotized, breeding young females are more likely to fail, and if it did success they tend to produce less eggs too. Not worth it especially for species like Xenesthis spp. where males can be very expensive too.
 
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cold blood

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Spermatheca on their ~6" molt are not sclerotized yet, so anything below 6" I wouldn't even bother to try. Depending on how you are measuring it, 4.5" is roughly N6 (DLS fully stretched) or N7 (Legspan not fully stretched) only and not matured.
Great info, helpful.
And even if the spermatheca did sclerotized, breeding young females are more likely to fail, and if it did success, they tend to produce less eggs too.
I don't necessarily agree with this however. In my experiences freshly matured females seem to be eager to drop sacs, in fact they are often the ones dropping phantom sacs. I have always had great success rates with young, but mature females.... especially with regards to fast growing species.

JME anyway.
 

heiwut819

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I don't necessarily agree with this however. In my experiences freshly matured females seem to be eager to drop sacs, in fact they are often the ones dropping phantom sacs. I have always had great success rates with young, but mature females....
Yes, I agree, getting viable sacs from old females is difficult and young adult females are often very receptive during pairing and more likely to proceed dropping sacs. I should have stated that's only my personal experience and clarify when I say young females I am referring to freshly matured once whose spermatheca just sclerotized. I've tried rushing it in the pass with some rarer species and most of those attempts failed.

From my experience they are also more likely to produce unfertilized or smaller egg sacs (compared to what the same female drop couple molts later). I don't have experience breeding any of the Xenesthis spp. but I did bred a few Pamphos and I reckon it'd be similar.

especially with regards to fast growing species.
Interesting point, and I think I'll have to agree too. Perhaps not exactly their growth rate, but their age and life span. Fast growing species tends to have shorter lifespans and thus older females in relative terms. I guess that's in some way "menopause" for spiders, though I am pretty sure there's no such thing hahah. But I'm quite sure there's a certain point they start to be less fertile, probably a few molts after reaching maximum size when their coloration starts to change (losing adult colors even when they're freshly molted).

On the same note, the 75% rule and how younger females are harder to successfully breed might just be us projecting the problems associated with teenage pregnancy in human to other species 😅, I am sure Ts themselves wouldn't care, if they want to breed they will.
 
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