Help in sexing B.jacksonis. (read mike's guide but there seems to be a prob with my pair)

The smaller one is the one in the first picture. second picture is the bigger one.

Both chelas seem to be the same, not bulbous. the dealer said that it's a male/female pair.

If it is a male / female pair, then the male hasn't matured yet. They both look like they have one molt left to go. If that's the case I'd guess the smaller one is the male.

thanks Mike.

awaiting other replies!

I havent got a clue but by the looks of it, they look like a boy and a girl at either end of a school dance not wanting to go near each other

xxxxxx

*Connie* wrote:

I havent got a clue but by the looks of it, they look like a boy and a girl at either end of a school dance not wanting to go near each other

xxxxxx

lol connie, ur full of helpfull information.
thats confirmed it...male and female for sure

i whould say both Females but if they are still in the 5 instar then they chould turn male or one of them

the dealer (who is a very reputable one) said it's a male & female pair and both are adults. . lookin at the smaller one, i doubt it's an adult. i have a feeling it's a male tho, it approaches the bigger one and does a swinging tail dance left n right.

Hey guys I've got clarification from the dealer. The male is the smaller one and is still a sub-adult. He sexed it via pectine counts! woohoo!

hmm oki? if its a pet store dealer i whouldnt still trust the guy.. but i whould still wait and see what happens when it hits final molt hehe

He's an online dealer from the Phillipines. Hopefully i do have a male and female. it's possible to sex male B. Jacksoni via pectine counts eh?

Actually, I've heard the pectine counts overlap . . . Does anyone have the pectine counts for this species? Even if they overlap, there's usually a "male-only" range and a "female-only" range.

Do u mind elaborating more on the overlapping thingy? wat exactly do u mean?

Say females have a pectine tooth count of 15 to 20, and males of 17 to 22 (just examples, I have no idea what the actual counts are).

Those numbers overlap, so you'd only know the sex for sure if you counted 15, 16 (the female-only range), 21, or 22 (the male-only range). I'll see if I can find the counts for this species.

From Michiel, a reliable poster on AB:

"You cannot sex B.jacksoni by pectinal teeth (18-24 for both sexes)."

http://www.arachnoboards.com/ab/showthread.php?t=89423

Hmm, okay. But u also stated that you've read that the pectine counts for this species overlap eh?

Probably the dealer sexed them via genital operculum. (just trying to remain positive)

Oh well, we shall see if he's right about a male and a female.

Also, Michiel stated that the bulbous chela will be visible from instar 5, do you agree on this Mike? If so, I doubt my 'male' has even passed instar 5 and I paid the price of a full grown adult.

I can never remember what instar the mature at . . .

Who knows, maybe the guy you got them from is good enough that he can sex them visually before they're mature.

its ok, the instar doesn't matter, i just wanna know whether the bulbous chelas are only visible during the final instar or..?

i belive that 6 instar is mature for females and males mature after 7 instar.. something like that..

Backwards -- females have one more molt than the males.

Liette, I guess we'll just have to wait until someone molts and then see.

Any info regarding sexing except the bulbous will be appreciate

IHeartMantids wrote:

Backwards -- females have one more molt than the males.

Liette, I guess we'll just have to wait until someone molts and then see.

You still have not answer my question Mike. lol.

I'll rephrase it again - Does the bulbous chela appear only on fully matured males or has it occurred in younger specimens?

I never noticed my male until after he matured -- in my experience, the answer is no.

However, someone who is very experienced may be able to notice the bulge before it is very obvious as in an adult.

Unfortunately I don't have an photos of my male in his second-to-last instar. I believe I have his exuvium, though. One moment.

Yup, here they are!

I have two exuviae that came from a male and female at equivalent molts (where the male matured and the female had one left) -- I can see no difference in the chela at this stage.


Two exuvia second from right I believe came from my male and one of my females.

Eh, from ur picture, does it mean that females mature at 6I and males at 5th?

That's correct.

Unless I lost my only 2I to 3I molt, then everything is +1. But males do mature one instar earlier than females.