Favoritos de kerrileeharris

Size 4.5mm body length.

Maybe Eupsenella sp. ?

Notes:
The most recent reviews of the genus were by Terayama (2004) and more comprehensively by Ramos and Azevedo. (2012) who recognised 45 species of which 38 were new.

References:
Terayama, M. (2004) Descriptions of new taxa and distribution records of the family Bethylidae (Insecta, Hymenoptera) II. Subfamily Bethylinae and fossil Taxa. Academic reports, Faculty Engineering. Tokyo Polytechnic University, 27, 39–41.

Ramos & Azevedo. (2012): Revision of Eupsenella Westwood, 1874 (Hymenoptera, Bethylidae). Zootaxa 3539 (1): 1-80, DOI: 10.11646/zootaxa.3539.1.1, URL: dx.doi.org/10.11646/zootaxa.3539.1.1

It really didn't help that I found this tiny wasp stuck in a water bowl, but its an interesting tiny critter. When I fished it out it paused for a moment, then crawled into a crack on our deck rail, looked angry and then flew off. I contemplated that this could be a bee, but I think it looks wrong in too many ways.

Following Bohart & Menke (1976) it keys to Paracrabro though unsure of other genera since described, specifically Allostigmus and Ceratostigmus for Australia.
In summary, wing with two discoidal cells, marginal cell closed and larger than stigma. Pronotal collar with complete transverse carinae. Gaster longer than wide. Hind tibiae with dorsal row of weak spines. Front of head as in Bohart & Menke (1976), Fig. 44C, including the medial cordiform process on the lower frons, but differing in the scape being shorter, reaching only about 2/3 eye height. Body length approx. 8mm.

Paracrabro froggatti
Identified as Paracrabro froggatti on Bowerbird by Ken Walker: "I am sticking my neck out here with this ID. There are no images of this species on the web and no records on ALA. The type specimen was collected in Victoria. Here are my reasonings: Due to the distinctive wing venation, this wasp belongs to the subfamily Pemphredoninae of which there are 3 genera: Ceratostigmus, Allostigmus and Paracrabro. There is a key to these genera is this 1999 paper: Melo, G.A.R. & Naumann, I. 1999. Two new genera of Pemphredonine wasps from Australia (Hymenoptera: Apoidea, Crabronidae). University of Kansas Museum of Natural History Special Publications 24: 221-229. The key characters for Paracrabro include: Female mandible with at least 3 pre-apical teeth, Pronotol lobe with conspicuous carina, vertex produced behind ocelli, petiole without transverse carina and in female the hind tibiae expanded." In this image you can clearly see the vertex is strongly produced behind the ocelli. The other 2 genera do not have the vertex produced behind the ocelli. So, on that basis I have placed this wasp in the genus Paracrabro of which there is only one species P. froggatti."