I think we can rule out Bethylinae. The members of this subfamily are generally in the 3-5 mm. range (except some of the Goniozus, and this is not in Goniozus). There should also be a sharp carina dividing the clypeus and extending to the lower frons between the antennal bases. The head would be quadrate, and lack this degree of sculpture. I still believe the venation visible in the photo (though not entirely clear) makes placing this in the known North American subfamilies of Bethylidae problematic. While the "bethylids" pictured from Japan do look similar to the picture from NJ, when I looked at them I see the overall appearance of a bethylid. When I look at the pictures we've discussed lately from North America I see tiphiids. I know that's not a scientific assessment, but the pictures don't show enough good characters in my opinion to say that they definitely represent something new to our fauna.

We have thunderstorms scheduled for the rest of the day today, but tomorrow I will print an uncropped image and take it outside with me and find the exact section of the siding where the wasp was located. I will then measure the pattern on the siding that the wasp's body covered and double-check my memory. This may simply be a "big fish story" on my part. If so, I apologize in advance.

As promised, I did measure my aluminum siding pattern and it appears that 8-10 mm is probably more accurate than 12 mm (see previous apology) I'm not sure if that changes anyones mind.
I have found some more comparison shots. Note that in my mind the Tiphids seem to have large eyes for their heads, where the wasp in question seems to have smaller eyes when compared to the overall head size.
Pristocera armifera (good match for head) http://www.cedarcreek.umn.edu/insects/album/025048001ap.html


Tiphia species (ration of eye to head seems different) http://cedarcreek.umn.edu/insects/album/025053001ap.html


Tiphid species (again seems a little "big eyed" for head size) http://cedarcreek.umn.edu/insects/album/025053ap.html

I agree that your specimen does look like the picture of Pristocera. Note the shape of the petiole and abdominal attachments in the tiphiid pictures when compared with bethylids. Its too bad we can't see anything of the abdomen in you picture. The more I look at your picture the more convinced I become that Richard is right about Bethylidae (in the Pristocerinae). I'll check the Catalogue of Hymentoptera when I get back to the office to see if they have any more information on the range for P. atra.

I tried to remove some of the spectrum that made up the wing color, hopefully leaving a better view of the abdomen shape? I do hope that I'm not wasting too much of your time having my fun. Perhaps your efforts and expertise would be better spent elsewhere, but I do appreciate the attention you both have shown.

When I look at the venation in the picture, am I seeing the evidence of the 2nd submarginal, and 3rd discoidal cells? These could be be just a few scattered vein traces that show because of the angles, but... I do see the strong marginal vein that seems to just disappear at its apex (bethylid-like), but again the angle...

If we try to place this into Bethylidae, then I think we need to look in the Pristocerinae. The best candidate in this subfamily would be a male Pristocera atra (the females are wingless). Evans places this species as far north as North Carolina (SE USA to Texas), size 6-14 mm. The head is strongly punctate and lacks the strong carina between the antennae. The anterior portions of the pronotum would be weakly rugose, the notalices would be prominent and straight, and the mesonotum shining, weakly punctate. Venation would include a scattering of faint veins in the region I just refered to above(if it is similar to Pristocera armifera). The wings are described as clear hyaline to moderately infuscate.

It would appear this Wasp is definitely a difficult one. While the Japanese "presumed Tiphiidae) specimen below (see John's comment) seems indeed to be a "cousin" of this one, I think there is at least one photograph in BG which shows EXACTLY the same insect: this is number 32853, by Tom Murray, provisionnally classed into Tiphiidae, This latter family is such a diverse, heterogenous group that this male could be one of them after all.
I'm afraid this case will remain a mystery unless a male is seen mating - the female should be easier to put at least at the family level.

I agree with you Richard, I've come to believe that this is in the Bethylidae, the Pristocerinae to be exact. I've the checked the distribution and size for the known species. With the size reduction from ca. 12 mm to 8-10 mm this now fits within the range for both Pristocera atra (to 14 mm) and P. armifera (to 9 mm). The distribution for P. armifera includes most of the east coast from New Hampshire south, P. atra would be from North Carolina south. The primary key character to separate these two species is whether the mandibles are curved along the lower surface or straight (armifera being curved). Other characters can not be clearly seen with the pictures provided. Both are black, but armifera is described as having legs, flagellum and abdomen dark reddish brown. The picture posted of P. armifera shows a specimen that looks black to my eye, and the tarsi do look somewhat brown in our "mystery specimen". What do you think of the mandibles in the picture? They look curved to me; which would mean Pristocera armifera.

Duplicate post

I know nothing about this web site, I was just using google. I found it an interesting parallel that in a photo album named "Bethylidae" there is a series of images titled "Presumed Tiphiidae". The center image appears to be a cousin to this wasp, although the "neck" area seems shorter (almost non-existent) but that could just be the angle.
http://xespok.net/gallery/Bethylidae