המועדפים של heatherholm

Crossocerus? I have at least four pics of this little wasp. I think it bears some resemblance to @heatherholm's nesting Crossocerus, but of course I could be mistaken. It does not appear to have pale rings on the top of the tibiae, though:
https://bugguide.net/node/view/1737573/bgpage
@matthias22

Heads up @neilvinson @laura_clarke @sinclvan6
This cool little cuckoo wasp was found in the pollinator garden during the 2021 BioBlitz. As far as I can tell, this critter is completely new for Eastern North America on iNat and Bug Guide. I will check with @matthias22 and @johnklymko whether there are any known records for this Genus in the region.

On Cicuta maculata blossoms on the border of a prairie pothole marsh. A breeding pair perhaps, they rubbed their antennae quite rapidly. A few minutes later I observed what appeared to be the same species of wasp lurking at the openings of the dens of larger wasps on a nearby sand dune -- maybe 200 meters away. [see" https://www.inaturalist.org/observations/28811923] If I understand the descriptions, these may be from genus Zanysson.

Cuckoo wasp stalking a Trypoxylon collinum nest. It wasn't successful on this occasion (male T. collinum eventually came out of tube and attacked it) but I saw it enter the nest a day later when the male was briefly out.

I don't have a good shot of distal part of abdomen, unfortunately. Caenochrysis? Chrysis?

On an aster (Symphyotrichum) in a sand prairie marsh and thicket area. The predominance of dark markings caught my eye. The flower is most likely Symphyotrichum pilosum, but Symphyotrichum ericoides is similar. This tentative ID is based primarily on the markings but I didn't see a really clear explanation of how to get yellowjackets to species so please don't rely on this until confirmed or corrected by an expert. Photos depict a single individual.

On a sunflower, probably Helianthus X cinereus, in a sand prairie near a marsh. These large Megachile bees were active and rather tame, and lighting conditions were good so I was fortunate to get quite a few good shots; the photos depict more than one individual. Helianthus X cinereus is not available as a choice on iNat so I've simply tagges as "Helianthus". I had formerly thought these were H. hirsutus, though they didn't key out all that well; in summer 2017 Laura Rericha, co-author of "Flora of the Chicago Region" informed me these are X cinereus, perhaps a hybrid of H. mollis and H. occidentalis, both of which are common nearby. Whatever you call them, they seem to be especially attractive to M. fortis. [see also: https://www.inaturalist.org/observations/19800354]

On Asclepias tuberosa in my mostly native sand prairie garden. Smaller than a honeybee, larger than a typical sweat bee. My initial impression was 'cuckoo bee' (eg Epeolus). All the photos depict a single individual.

In a fishless, sand bottomed pond with clear, clean water. ID using: http://fwf.ag.utk.edu/mgray/wfs493/HovermanLarvaeID.pdf - Also, the only species of salamander that has been seen in adult form in the area. However, I didn't see the blue-spotted salamander in the key and the habitat for that species is potentially available. Photos are probably not of the same individual. In the third photo, the salamander tries unsuccessfully to eat a large wormlike creature, possible some kind of leech.