Identification of Wasp Larvae from Mason Bee tubes

Wings held partly erect.
Wings held partly erect.

In the previous post I indicated I was trying to identify wasps that had taken up residence in mason bee tubes, without actually parasitizing the mason bees

 

 

largewasplarvaeI found the larvae in tubes while removing the mason bee cocoons in the winter, and transferred them to a separate jar where I  let them hatch. By May 1 they were hatching so after taking a few pictures, I sent the images off to BugGuide.

The result after several months was an identification by an expert in entomology : Our thanks to  Matthias Buck of  The Invertebrate Zoology Section, Royal Alberta Museum, Edmonton, Alberta, Canada
http://bugguide.net/node/view/1218699#2158789

So he thinks there are actually three species represented in these pictures.

Food
Eumenines prey mainly upon moth larvae, although some take larvae of leaf-feeding beetles.
Adults take nectar.
Classification

Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Hymenoptera (Ants, Bees, Wasps and Sawflies)
No Taxon (Aculeata – Ants, Bees and Stinging Wasps)
Superfamily Vespoidea (Yellowjackets and Hornets, Paper Wasps; Potter, Mason and Pollen Wasps and allies)
Family Vespidae (Yellowjackets and Hornets, Paper Wasps; Potter, Mason and Pollen Wasps)
Subfamily Eumeninae (Potter and Mason Wasps)
Genus Ancistrocerus

There were three species identified from my photographs( labelled above) although it is very difficult to confirm identity without being able to examine a specimen. Next year I will be sure to send him samples to confirm, and I will certainly not destroy these larvae when cleaning out mason bee tubes.