Theory: Ventral sexing might actually be good

Moakmeister

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Ventral sexing, as I am to understand it, works like this: a female's first set of book lungs are farther apart than a male's, which are almost touching. This technique is infamously unreliable because every tarantula has a slighty different body, so it's usually just better to use a molt. But here's my theory: it could be good, IF you are using it on a big group of tarantulas. If you ventrally sex a big group, then the one with the farthest apart book lungs is almost certainly female. And the ones with the closest lungs are almost certainly male. I would liken it to how men tend to be taller than women, even though there are exceptions. But over a large group of people, the men will have a taller average height. So what are y'all's thoughts?
 
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Chris LXXIX

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I'm not a fan at all, nothing beats the old good exuvia "Sherlock I.D" IMO.

Aside for 0.1 Pelinobius muticus :-s for that males do not possess those unique rear legs like females.
 

Moakmeister

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I'm not a fan at all, nothing beats the old good exuvia "Sherlock I.D" IMO.

Aside for 0.1 Pelinobius muticus :-s for that males do not possess those unique rear legs like females.
I'm still holding out hope that @cold blood may have what I'm looking for, but he hasn't been online since Saturday so I don't know yet.
 

EulersK

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I'm still holding out hope that @cold blood may have what I'm looking for, but he hasn't been online since Saturday so I don't know yet.
That's not all that goes into ventral sexing. Furrows and the 'lip' are also looked at.

As for his spiders, they're starting to get at the size that they can be sexed (via the exuvia, not ventral) with confidence. I've sexed all four that I've gotten from him.
 

Moakmeister

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That's not all that goes into ventral sexing. Furrows and the 'lip' are also looked at.

As for his spiders, they're starting to get at the size that they can be sexed (via the exuvia, not ventral) with confidence. I've sexed all four that I've gotten from him.
I'm so exciteeeeeeed
 

Venom1080

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Ventral sexing, as I am to understand it, works like this: a female's first set of book lungs are farther apart than a male's, which are almost touching. This technique is infamously unreliable because every tarantula has a slighty different body, so it's usually just better to use a molt. But here's my theory: it could be good, IF you are using it on a big group of tarantulas. If you ventrally sex a big group, then the one with the farthest apart book lungs is almost certainly female. And the ones with the closest lungs are almost certainly male. ?
no, ive never heard of anyone sexing solely based on how far apart the first pair of book lungs are. its all in the lips and furrow shape.
i pretty much only vent sex, it gets real easy if you practice in the sexing gallery here on AB. i rarely molt sex spiders.
 

Moakmeister

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no, ive never heard of anyone sexing solely based on how far apart the first pair of book lungs are. its all in the lips and furrow shape.
i pretty much only vent sex, it gets real easy if you practice in the sexing gallery here on AB. i rarely molt sex spiders.
Sweet. @Grasshopper99 and I want to make a deal for a female Grammostola pulchripes female, but he has no molts. We could use your help.
 

EulersK

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i pretty much only vent sex, it gets real easy if you practice in the sexing gallery here on AB. i rarely molt sex spiders.
I had a B. vagans that I 100% swore was a female, and many AB users agreed via ventral sexing. He still taps at night.
 

Venom1080

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I had a B. vagans that I 100% swore was a female, and many AB users agreed via ventral sexing. He still taps at night.
i never claimed im right all the time. ;)
in fact, most of my NWs have me confused, im much better at OWs.
 

REEFSPIDER

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I had a B. vagans that I 100% swore was a female, and many AB users agreed via ventral sexing. He still taps at night.
I swear to god same spider same story. Bought my juvy vagans as a female the guy at the shop swore it was female. I looked and suspected female. Many fellow hobbyists said the same and hes tapping now.

Edit: this spider im refering to was one of maybe ten they had sub adult at the shop i purchased it from and this one was by far the gurthiest and had the largest (mock) furrow.
 
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KezyGLA

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Ventral sexing can be good for some species as there are more obvious differences. A lot of species can be near identical and cause problems with ventral sexing. Thats why it is essential that exuviae is examined to look for the utera or spermathcae.

The plumpness of abdomens can also play tricks on the eye when it comes to ventral sexing.
 

cold blood

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Ventral sexing can be good for some species as there are more obvious differences. A lot of species can be near identical and cause problems with ventral sexing. Thats why it is essential that exuviae is examined to look for the utera or spermathcae.

The plumpness of abdomens can also play tricks on the eye when it comes to ventral sexing.
I agree.

And looking for "plumpness" is a complete waste of time....the only thing plumpness will tell you is how recently it molted. Prior to maturity, males and females of most species are pretty much identical.
 

Haksilence

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I agree.

And looking for "plumpness" is a complete waste of time....the only thing plumpness will tell you is how recently it molted. Prior to maturity, males and females of most species are pretty much identical.
+1 also thus why looking at the booklungs is worthless, if you are going to take a determine a "suspected sex" (because its never 100% and should not be marketed unless 100%) by ventral ID then you need to look at the other identifiers, the difference in booking distance is highly variable differing depending on how well-fed/recent the last molt was.
 

viper69

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Ventral sexing, as I am to understand it, works like this: a female's first set of book lungs are farther apart than a male's, which are almost touching. This technique is infamously unreliable because every tarantula has a slighty different body, so it's usually just better to use a molt. But here's my theory: it could be good, IF you are using it on a big group of tarantulas. If you ventrally sex a big group, then the one with the farthest apart book lungs is almost certainly female. And the ones with the closest lungs are almost certainly male. I would liken it to how men tend to be taller than women, even though there are exceptions. But over a large group of people, the men will have a taller average height. So what are y'all's thoughts?
Examining a molt is the only 100% guaranteed method for determining the gender of a T with but a few species that may be sexed ventrally via the "dot method", before you ask, search the forum.
 
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