Hadrurus arizonensis pectine counts

GQ.

Arachnodemon
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I just snapped a couple photos of my Hadrurus arizonensis for the purpose of counting their pectines. I placed them in a ziplock back and flipped them over. Taking in focus photos of them through the ziplock bag was a bit frustrating. Somehow I managed to take a photo of each. The photos won't win any awards, but they at least allowed me to count pectines. I'm seriously considering building a nice glass restraint setup the way Dave illustrated in an issue of Arachnoculture.

I then opened up the photos with paint and clicked on each pectine with a dot as I counted it. I ended up with the following counts for each.

38 on one side and 39 on the other side. Verdict: Male


29 on one side and 29 on the other side. Verdict: Female.


Female from above.
 

JSN

Arachnodemon
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good idea, and very nice looking arizonensis...
 

GQ.

Arachnodemon
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Thank you. I couldn't see any other way to accurately count them. They were really easy to count with Paint. Putting a dot on each one kept me from recounting or missing any pectines. I will use this method with scorpions from here on out. Now I just need more scorpions. :)
 

Prymal

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Gilbert,

You could have simply examined the space between the inner teeth of the pectines - short space = male; wide space = female!
On your photos, note that if the pectines of the male were swept back further the proximal (inner) teeth of the pectines would touch or overlap. On the female, this would be almost impossible due to the gap that exists between the L and R pectines.
 

GQ.

Arachnodemon
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Luc,

Thanks for the tip. I will keep that in mind next time I sex a Hadrurus. I noticed the difference in the space between the inner pectines when I was looking at the photos. However, I wasn't sure if the difference was due to her larger size or if it was a true means of identifying sex. Next time I'll know!

Thanks,
Gilbert
 
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Prymal

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Heya Gilbert,

Of course, the PTC is the most accurate means of identifying the sexes, the gap between the pectines is a very good and quick way of sexing Hadrurus.
However, I do like how you've taken to counting the pectine teeth - great idea!

Take care...Luc
 

final-sting

Arachnosquire
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@prymal look at the gap between the pectines its a good idea and new for me.

Hmm i have here a spadix, he have 33 teeths. Here http://bultel.p.free.fr/En/Hadrurus%20sp.htm for arizonesis M=32-37 Fem=24-31, spadix M=38-39 Fem=30

I think the pdf here its better: http://digitallibrary.amnh.org/dspace/bitstream/2246/3695/1/N1298.pdf Site 5
Male=35-40 Fem=26-33

So my spadix with 33 muste be a fem! But iam not sure, here pic, the secound its big so you see it better





I want buy a partner, so you can help me realy ;)
 

Prymal

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Sting,

Judging from the above photograph, your specimen is indeed a female. It's a bit hard to explain without proper illustrations but I'll give it a try!

What you're looking at is the anterior portion of the space between the pectines and the width of the space between the pectines and the angle formed by the anterior portion of the space and the inner (proximal) pectine teeth. In females, this shape is roughly square and in males, the shape is triangular or sub-triangular.
Also, you have to envision the position of the pectines when swept inward. In males, the inner pectine teeth will touch or overlap during rest. In females, in order for the teeth of the pectines to touch, the pectines would have to be swept back to an unnatural position in order for the teeth to touch.
Look at your second photo. In order for the proximal pectine teeth to actually touch, the pectines would have to be unnaturally positioned almost parallel to each other.
Now, this is not 100% accurate but is a good gender determiner in 95% of specimens.
 

final-sting

Arachnosquire
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Her i have a pic from my old dead arizonesis, clearly a male. 39 teeths


When i watch this old pic with my new spadix, the form of pectines looks very similar. Maybe a male too?
The smal body form looks for me a littel bit like a male>




My problem, i want breeding, but for buying a male and a female i have not enough space.
Maybe prymal you have a gravid arizonesis for sale?
much Thanks
 

Prymal

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Sting,

This is one of the problems with Hadrurus species - there is NO easy way to determine gender and no method including PTC is 100% accurate.
As I'm not a professional, I'm going to send the above photos to a good friend who's working on the taxonomy of US scorpions. Hopefully, he'll be able to shed some accurate light.
 

Prymal

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As for extra specimens. At present, I have 2 gravid fems of H. spadix. As soon as either parturates, I'd be glad to send ya a few offspring as I'm just about over-loaded with offspring from various species and still have many gravid fems! Next year, no breeding! LOL
 

final-sting

Arachnosquire
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yeah thats a very good idea! thanks a lot for your help!

ok when you have somthing for sale give me a message :clap:
 

Prymal

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Sting,

I've been going over the photo of your H. spadix and due to the angulation of the pectines, it has to be a female, no question. Now, you need to get yourself a male!
I'm still going to confirm it with my friend but I'm standing by my determination.
Based on the angulation (forget the pectine teeth) at the base of the pectines, it has to be a female!
 

Prymal

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Sting,

Just checked my email and received a reply from my friend just back from Mexico. He confirms my earlier determination that your H. spadix is indeed a female.

Take care...Luc
 

Prymal

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Sting,

At present, the PTC (Pectinal Tooth Count) is the most accurate method for gender determination.
When you do get a male, keep the two separated for 7-10 days and condition them on a good varied diet before introduction. The courtship and mating sequence is almost identical to that of H. arizonensis with the exception that males of H. spadix very rarely utilize a "sexual sting" during courtship.
Good luck!
 

final-sting

Arachnosquire
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prymal, 7-10 days in the same box with a partition wall ?

I have a male and fem of a mesobuthus. I hold it seperat, but yesterday i take the mal to the fem. Its the first time i see this, the male start direct to shake, and want the fem grab. Unfortunately my female have no intress for mating :rolleyes:
But peaceful, no mating but good she eat him not :D . Maybe she its gravid, but i think not.

You know a shop who sale hadrurus,mafia scorp, and maybe a smeringurus mesa? For shipping its 30$, so its better only 1 shipment from one shop, when possible.
 
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