Pseudomasaris coquilletti

On a Milkweed!

Interesting to see her feeding on Asclepias. I wonder if the milkweed nectar will be mixed with pollen for provisioning a larva, or if she's strictly feeding for her own energy needs here?

I was under the impression Pseudomasaris were oligolectic to genus: i.e. that a given species of Pseudomasasris would only provision their larva with a pollen/nectar mixture from flowers within a single genus of plants...and that (at least in CA?) those host plant genera were limited to Phacelia, Penstamen, or Eriodictyon. In that case, knowing the host plant helps ID to species.

… Aaron Schusteff, 22 April, 2011 - 9:54pm

This species is indeed oligolectic

on Phacelia, at least for pollen. Nectar is also used as flight fuel, as you suggest. Many pollen specialists, as Doug Yanega told me some years ago, will still use other plant species for nectar. The gathering of pollen and feeding on nectar are separate activities.

This female was only my second observation of pollen wasps. At the time I still thought, based on some early reading, that they used Penstemon. I've since learned, also by own observation, that almost all spp. of Pseudomasaris use Phacelia both for pollen and nectar.
You may prefer getting your gasoline at a certain station, but if you're out of gas you'll have to make do with what's nearby. At the time there was no Phacelia in the area.
I recommend reading "Plant-Pollinator Interactions" (2006, Waser & Ollerton, eds.; (1))

… Hartmut Wisch, 23 April, 2011 - 1:40am

male

According to Howard E. Evans, only males have clubbed antenae.

… Adalbert Goertz, 11 April, 2007 - 8:45pm

Well,

I don't think that Evans meant this categorically. One of the diagnostic characters of Masarinae (at least in North America) is a clavate (club-shaped) antenna. Those of males are just considerably bigger and more spectacular than the antennae of females. We have a couple of images of males on bugguide; for an example see here: 1 .
I don't have time to look it up right now, but I'm certain that a careful reading of H.E. Evans will yield the same results.

… Hartmut Wisch, 11 April, 2007 - 9:08pm

Superb shot

Showing the long mouthparts (essentially the glossa of the labium) of this female "diving" into a flower to reach the nectar.
Males should also be present in the area, but likely more difficult to spot and still more to "capture", especially in such an impressive way.

… Richard Vernier, 21 May, 2006 - 12:33pm

Thanks,

I was glad to see another Pseudomasaris, and to have a relatively 'cooperative' subject. Penstemon centranthifolius is beginning to bloom in the area, and I wonder whether I'll see these pollen wasps feeding in those flowers.

… Hartmut Wisch, 22 May, 2006 - 1:13pm

Cooperative or just caught?

This insect may be caught up in the milkweed's pollinarium.... Great shot at any rate. Mike

… Mike Quinn, 1 November, 2006 - 5:44pm

Probably not caught

in this case, it soon changed position.

… Hartmut Wisch, 1 November, 2006 - 5:59pm

Exquisite.

I'm running out of adjectives to compliment your images with:-) Yes, you should see Pseudomasaris females gathering pollen from the Penstemon. Be on the lookout for males, too. They have bizarre, long, clubbed antennae.

… Eric R. Eaton, 22 May, 2006 - 3:59pm