I took him out of the refrigerator last night....he's still alive, although he sure doesn't feel to good.

And yes, I know males can't sting. As a matter of fact, as noted in one of my comments below, while taking the pics of the parasites I held and manipulated the wasp in my left hand, trying to get a good position, and operated the camera with my right hand.

Well, I have some bad news....this wasp has gone to that big nest in the sky. I've been checking him every day and when I checked last night he wasn't moving.

So, now what ? I still have him in the baby food jar but should I try to extract the Xenos and take pics of it or should I just let it be and see what happens ?

If the host is dead the Strepsiptera dies too. If you want to see the whole beauty of it, try to dissect it and get a pic of how big the female is. Then you can place everything into a vial with 75% alcohol and give it to a collection...
If you leave it, it will just dry out and the specialists prefer to get these insects in alcohol...

I'll do it tonight. Do I use just plain old rubbing alcohol ?
If you have somewhere you want me to send it let me know.

You can take any rubbing alc or ethanol 75% (look in your booze shelf, there are some drinks which have a high enough concentration, but rubbing alc is chaeper). I will look for a good address to house the specimen..
cheers
Martin

Any word on this yet ? I have been contacted by Jeff Gruber at the University Of Wisconsin. He says he will send to Dr. Steve Taylor at Illinois Natural History Survey for positive ID then put it in the University of Wisconsin-Madison museum. But, I was waiting to hear back from you before deciding what to do with it. Please let me know.

Steve will surely tell you that this is the genus Xenos, I am not sure if he or anybody else can ID the species, because it is not so clear how many species there are in this genus. You can send it to Jeff, that would be fine with me. There are only 2 "Big" specialists for this group, Prof. Hans Pohl in Germany and Prof Kathirithamby in the UK. I am a good friend oh Hans Pohl, but I already sent him several Polistes with Xenos, so it would be much better to store this specimen in a US collection. So feel free to send it to Jeff.
Here is Steves webpage:
http://www.inhs.uiuc.edu/~sjtaylor/strep/Strepsiptera.html
Cheers
Martin

That is AWESOME !

if these parasites harm or even kill the host wasp?

Strangely they do not harm the host so much, although if you see how much space they need inside the wasp, you can not believe that the wasp is not greatly affected. In fact there are some indications that especially male wasps which are stylopized live longer then the "normal" ones. Often the wasps are not fertile and when bees are stylopized they emerge earlier then the rest of the population. So when you are collecting e.g. Andrena bees in spring, the first ones flying are often with Strepsiptera inside. When the male Strepsiptera emerge, they live only a few hours!

The term "parasite" indicates that they are dependant on the host to survive, similar to a tick. So what do they eat....part of the wasp ?
And why do they parasitize wasps and flies and not other critters ?
Is the very lethargic state of this wasp due to the parasites and if so, why ?

If they were parasitoids, they would kill the host, like Ichneumonid wasps would do.. But the females of Strepsipteran always stay inside the host, so they need them to live for a while. They use the nutrients floating in the heamolymph (insect blood) of the host. Many Strepsipteran live in bees and wasps, many in leafhoppers and true bugs, some in Preying mantis (females) and the males in ants (very strange), some in Silverfish and very few in flies (only in Australia).
Of course they are weakening your wasp and the colder weather does not help, also it is fall and the male wasps are dying now because they are too "old".

Hi Martin.

Do you think there is still a chance of emergence this late in the season? I asked Sam to put the wasp in a container, with some damp paper towel, in the fridge in the hope of keeping it alive until I could get some advice. Would it be better off at room temperature? Should it be fed something?

I took a glance at the pics and it seems that there was one empty male puparium and the second one could be a female. So it could be that nothing else, except the larvae, will emerge from this wasp.
It is defenetly worth keeping and depositing it in a collection. The INHS is a good place for this...

Thanks for the info. Very interesting critters....and strange.

But, are you saying they aren't parasites ?

They are parasites. There is a fine distinction between parasite and parasitoid. Both feed on their host, but parasites never (directly) kill their host (like fleas, lice, etc) but parasitoids eventually kill their host because they consume too much tissue of the host (Ichneumonid wasps, Tachinid flies etc).

I appreciate all the information and explanation !

thanks for clearing stuff up about the parasites! i am keeping a queen P. fuscatus right now, and she has one of these parasites. im glad it wont hurt her!

Definitely looks to be a male P. fuscatus. They are so darn variable!

Where is the parasite ?

The gap between the ultimate and penultimate visible (in your pic) abdominal segments probably indicates stylopization. See . Great find! Do you have the wasp? It would be great to get some shots from the posterior.

But, I will look when I get home this evening and see if it might still be there. It stayed in the very same spot all day yesterday so I'm hopeful it will still be there.

Please collect it, if you find it again and you are not opposed to killing and preserving insects for scientific research. Strepsiptera are relatively uncommon and I'm sure Strepsiptera researchers would definitely appreciate the specimen. If you do collect it, throw it in a container in the fridge and let me know.

I found him. He wasn't in the exact spot as he was yesterday but I found him. I have him in a container. Now what ?

I'm going to take some more pics of him tonight

I have contacted the Strepsiptera researcher at Illinois Natural History Survey and am waiting to hear if he wants you to keep it alive in hopes that an adult male might emerge (if it is a male pupa and hasn't yet emerged). It would be great if you could keep it in the container (with a piece of damp paper towel) in the fridge. I (or he) will get back to you soon.

Looking forward to the pics.

BTW. Great job on your photographic skills progression. I have been listening in on the Photography Forum as I may attempt a similar endevour in the future. I currently use a P&S in the field, but these animals deserve better.

I will have the pics upload in about 10 minutes. As far as I can tell there are two parasites.

By the way, are the parasites causing the lethargic reaction in the wasp ? Are they killing it ?

Pics are uploaded. These were hard to get because I had to hold and manipulate the wasp in my left hand and operate the camera and tripod with my right....I'm not sure I'm that coordinated.

Nice pics.

Looks to me as if they are male pupae (see here). Hopefully if you keep the wasp alive they will emerge. I have asked the Strepsiptera researcher if he thinks they might emerge this late in the season. It would probably be best to keep the wasp in a clear container with some damp paper towel and some very small (pin-hole sized) holes in the cover, in the fridge. I will let you know when he gets back to me.

Thanks for your efforts. I can't believe you found it.

Right now I have it in a baby food jar. So, you want me to put a damp paper towel over the top then screw the lid back on, correct ?

Should do the trick if you put it in the fridge. Hopefully we'll hear something tomorrow.

Done. Just waiting to hear....

Although I don't think my wife is too excited about having a wasp in her refrigerator !

So the wasp is Polistes of some sort but the parasite is Strepsiptera, correct ?

You can just go right ahead and pick it up. Males cannot sting. Though they will act like they can LOL