Torymid wasp in the genus Monodontomerus, found as one of many around an artificial habitat for leafcutter bees (bamboo tubes). Not having access to Grissell's revision of the genus (1), I used his paper on torymids associated with bees (2) where it appears to key out to Monodontomerus aeneus, an introduced Palearctic species. However, I'm not sure I can really distinguish it from M. obscurus (according to Grissell these are, "among the two most difficult species of the genus to distinguish from each other" (2)). According to the character states in Grissell's key, the intrusion of the frenum into the apical rim is indicative of M. aeneus. However, the amount of sculpture on the frenum and the ventral part of the mesepimeron might be more consistent with M. obscurus. I should point out that Grissell states that the proximal and distal segments of the postmarginal vein should be subequal in those 2 species but they're not in this individual so I may be way off on the species ID.

I can't find any useful photos or detailed diagrams on the web that would help distinguish between the 2 species. If someone out there can help nail down the species ID or knows where suitable diagrams/images can be found, I'd appreciate the help. TIA

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