Sexing E. olivacea slings/juvies

[jbm150]

Is it possible? My little one surprised me with a molt and today I looked at it under scope. Ventrally the spider looked male but the the exo showed...I dunno. I know this species doesn't have spermathecae but females do have a uterus externa (usually visible at 3+"). In my molt, it didn’t seem to have the area of epiandrous fusillae, the spot, as it were, I’m used to seeing for males. And there was something else present, a very thin flap or bag-like thing, posterior to the epigastric furrow. I couldn’t tell if it was just loose material or was a pouch or what it was. It didn’t really look like a uterus externa and besides, this was in a 2” spider. It seemed fairly large and again, it was posterior to the furrow. I’ve seen the term bursa copulatrix; this seemed to come from that location. I've never seen something quite like it in any of my other Ts, male or female. Anyone have thoughts on that?

Also, does anyone have any pics of a molt of these species that isn’t subadult or adult? I’ve searched and have only found pics from mature Ts.

I wish I had taken a pic through the scope; I didn’t because I don’t think it would have shown what I was seeing…..

 

[Amoeba]

I don't know too much about this species but I was under the impression that they are sexually dimorphic. I'll look for a pdf about it.

 

[catfishrod69]

I thought that they were lacking the spermethecae, but still have the flap?

 

[jbm150]

They are dimorphic upon maturity, I'm looking for well before that time. They do have the flap, the uterus externa, but I didn't think it was visible before 3". I knew I should have taken a pic, at least it would have been archived for future reference :/

 

[catfishrod69]

Well i have found the flap on other species smaller than 3". I have yet to get any olivacea, so im not sure if that applies to them too.

 

[advan]

This is a very good question. I would like to know if syndicate has any thoughts on the subject. I have one that looks female to me ventrally but I haven't even attempted to sex it via molt yet.

Would do you think?

 

[syndicate]

Hi guys,
I did not think you could sex this spider ventrally so I never bothered trying..According to a post by Anastasia in the photo forum she says it is possible and to look closer! So I doubt she would make that up hehe!I have no idea what sex the above photo would be but to Jeff (jbm150) I think this is what your looking for?

You can read the full article here:
http://my.opera.com/misticVStooth/blog/show.dml/5539691

Hope that helps guys!
-Chris

 

[jbm150]

Good stuff, thanks Chris. The flap I saw looked a lot like a uterus externus (I keep screwing that up) but this is still a very young spider (it was large) and it seemed as if it came from the location of the bursa copulatrix. I guess I'll have to wait again until the next molt and take pics. I find it a lot of fun when I can sex small spiders and frustrated when I can't lol

 

[Anastasia]

I can see ventral difference in specimens that aprox 3", even so its a bit tricky and they look very much alike.
also in 3" uterus externus pretty well visible in the molt.

 

[Protectyaaaneck]

Here are two juvies from Syndicates 1st eggsac:

#1

#2

I would guess male on the first one and female on the second. They are both about 2.5-3".

 

[jbm150]

My little one finally molted again, I had taken some ventral pics a while back but discarded them because they clearly said male. I didn't think there was much question. Buuuut, I sexed and photoed the molt and lo and behold:

Arrow points to flap. The pic isn't that great but it's the best I could do with such a small specimen. With the probes, I could flip it up and down. It's clearly a large flap of exo and presumably the uterus externus. SO it's a girl....right? lol

I'll try another ventral shot when I get a chance but seriously, if it was a pokie, there would be zero discussion about it. Seems this is a tricky species....

 

[syndicate]

That's one hawt looking uterus externus right there ;]
-Chris

 

[jbm150]

Sweeeeet, thanks Chris!