Ventral sexing of Brachy's

julesaussies

Arachnobaron
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i'm pretty sure i have read a post or article about this before but now can find it anywhere. If there is such an article - can somebody help me find it. i have spent some time looking and practicing ventral sexing of Brachy's from the pics on that section. What i am looking for is a descriptive explanation of what exactly i am looking for. Thanks so much! jules
 

Talkenlate04

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Ok well between the anterior book lungs right above the epigastric furrow, there would be a tight dense patch of hair in a half circle type shape. The darkness and shape of that patch varies from species to species but is present, and when present indicates male. Incications you have a female are, the epigastric furrow itself on females has a slight buldge, and right on the furrow normally in Brachys there is a curtain of hair pointing downward, and that half circle I am speaking of is not present on a female. Once you have a male female compairson and you see it in real life it gets easier to spot as you go. It take some practice but once you get it and see that difference Brachys can be sexed accuratly at 2"+ with ease.
 

julesaussies

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Ryan

Thanks Ryan,

Hey, seeing how i don't have a lot of real life specimens to practice on i was wondering if you could check out a few of these pics to tell me which have thet most obvious signs i will see in real life - just so i have a more clear idea of what i should see.

i looked through a lot of pics and think these might be the closest to real life:

1 - Is the dark half moon above the epigastric furrow in this B. smithi male typically that obvious in a male in real life?

http://www.arachnoboards.com/ab/gallery/showimage.php?i=2574&c=9

2 - How about this B. smithi female - i can clearly see there is no dark half moon of hair, but consistantly lighter between anterior book lungs - is this a good example of a real life female? i think i can barely see the curtain of hair pointing downward that you mentioned. Is it that vague in real life?

http://www.arachnoboards.com/ab/gallery/showimage.php?i=2032&c=9

i was more confused on these:

3 - i definitely don't see the dark half moon nearly as obvious in this B. smithi male. That whole area looks dark to me. Is that most likely because its a photo and that T would look more male in real life? i also thought i saw the curtain of hair pointing downward but obviously i'm wrong - perhaps i'm looking in the wrong place.

http://www.arachnoboards.com/ab/gallery/showimage.php?i=3639&c=9

4 - In this female i was at first confused because she was so dark between her anterior book lungs - again maybe lighting with the pic. If she had been a male there would have been an even darker half moon there, right? However, her slight buldge seemed more obvious.

http://www.arachnoboards.com/ab/gallery/showimage.php?i=3819&c=9

5 - Okay, this B. smithi is unsexed by anyone. i don't see an obvious dark half moon like the first obvious male example but maybe due to lighting? There does look to be a dark line but not the real obvious half moon. The buldge if any isn't as obvious to me in this pic as others i have seen but that seems to be the one thing i have the most difficulty seeing. Is the buldge in a good size female Brachy pretty obvious in real life? Not sure i can see curtain of hair - maybe with closer pic... What is this one and what do you see in this pic that makes it obvious?

http://www.arachnoboards.com/ab/gallery/showimage.php?i=3937&c=9

i know it takes looking at a ton of male and females in real life. Like i said, i'm just trying to get a more obvious idea of what i'm looking for when i do get the opportunity to see some real T's.

Sorry this is long. If you don't have time to check all this out don't worry about it. i just find this very interesting.

Thanks a ton!! jules
 

julesaussies

Arachnobaron
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Thanks

Rick West has the best resource on sexing tarantulas ventrally.
http://www.birdspiders.com/faq_sex.html
Thank you. This article was very helpful. Now i am anxious for my OBT's to show me their belly's on their own as i have no immediate plans for picking them up. :eek: LOL

i just wish the article would have shown more examples of the Brachy's since that is what i would like to become most competant at first. However, his pictures were very good in that they were consistant and showed exaxtly what he was talking about. i'll have to pick up one of those 30x microscopes with a built in light tomorrow and wait and hope for my OBT's to show me thier stuff!! Thanks a lot!! jules
 

Talkenlate04

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That first picture is a great example of a male. That patch that you clearly see in that photo you will see in varying darkness and lightness depending on the age of the male. It becomes more defined when they are older, a tad bit harder to spot the younger they get.
Same goes for female characteristics, that second picture you have is from a younger female maybe around the 3-4" mark. As she gets older the female parts will become more pronounced.
That third picture its the lighting and the angle of the picture thats messing with you. Thats one of that hardest things about ventral sexing someone elses picture via the computer. I happen to know who owns that one and it was confirmed male via molt. But that picture is a good example of how hard an online picture can be when it comes to ventral sexing.
The forth picture is also a younger specimen, maybe 3" but the female charateristics are visiable. (this is where practice will come in over time.)
Your last picture hates me and I cant get it open......{D
 

julesaussies

Arachnobaron
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THANK YOU!!!
Ryan,
Thanks for taking the time to look through all those Brachy pics and answer my questions. i really appreciate it. i had a feeling many pics don't often represent exactly what the T's look like in real life. Now i have a very good idea of what i'm looking for in real life, specifically on Brachys, when i get the opportunity.

i also found the article by Rick West to be helpful. i definitely want to check out my bigger OBT's when the opportunity presents itself.

Thanks, jules
 
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