Pseudomasaris sp. provisioning cells - Pseudomasaris edwardsii

Moved

Moved from Pseudomasaris.
After seeing females of both edwardsii and coquilletti today, I'm convinced that this is indeed P. edwardsii.

… Hartmut Wisch, 1 May, 2010 - 9:39pm

Moved

Moved from Pollen Wasps
The only masarine wasps in North America are in the genus Pseudomasaris.

… Hartmut Wisch, 16 April, 2010 - 12:25am

I took another look at this photo

last week. Though it looked to me like edwardsii at first, based on the dorsal markings, as well as how I saw the propodeal spines. What's not visible is a diagnostic anterior bump, or prominence, near the middle of the mid tibia; only edwardsii females have this (see INFO page). The angle of this shot may just not show this.

However, this could also be coquilletti, which can be quite similar, though a larger species (~14-16mm, vs.~10-12mm). Pattern on the side of the thorax reminds me of coquilletti, and dorsal markings can be quite similar. When you look carefully, you can see parts of a long, yellow stripe on the dorsum of the thorax. Some important characters can't be seen in this photo. For instance, in coquilletti the yellow of the upper orbitals (around the eyes) are clearly produced toward the ocelli, see here, also note the two long stripes on the thorax:

P. edwardsii female; upper orbitals not produced toward ocelli, two shorter hatchet marks on thorax:

Summary: it could be either one. Do you recall the size?

… Hartmut Wisch, 14 April, 2010 - 5:33pm

Hello Hartmut, My sense i

Hello Hartmut,

My sense is that this species was smaller than the P. coquilletti that I posted yesterday and probably in the 10-12 mm range. I have 3 other shots of the same animal, but all the views of the mid tibia are from the posterior.

… Jonathan Wright, 15 April, 2010 - 1:22pm

Perhaps

P. edwardsii after all? Nest styles don't differ from one species to the other, except for nests in vegetation by vespoides.
If you don't mind either posting the other pics, or e-mailing them to me, I'd be interested in taking a look at them.

… Hartmut Wisch, 15 April, 2010 - 1:34pm

Other images

Not sure if these can provide any additional clues!

… Jonathan Wright, 15 April, 2010 - 2:35pm

C'est la vie -

I consider this photo most important not so much for which species of Pseudomasaris it represents, but that it shows one of those not easily found nests. A wonderful addition to these pages!
There'll be more wasps to look for this spring, principally in the patches of Phacelia, and the Eriodictyon.

… Hartmut Wisch, 15 April, 2010 - 6:20pm