The Rattlesnake Master 'flowers' have been very popular the last 3 or 4 days. There are a wide variety of insects/pollinators visiting the stands in the prairie. Most interesting is the variety of wasps visiting them.

Eryngium yuccifolium, commonly called rattlesnake-master or button snake-root, is a Missouri native plant which occurs in rocky woods, prairies and glades throughout the State and was a common plant of the tallgrass prairie. 
The yuccifolium species name refers to its yucca-like leaves which give it its desert plant look. The common name rattlesnake master reflects the plant's relationship to American Indians. Some Indian groups were known to make a brew by boiling the plant's roots as an antidote to rattlesnake venom. Some native peoples would also use the dried flower stalks as ceremonial rattles. Other common names in use are button eryngo, button snakeroot, yucca-leaf eryngo, rattlesnake flag, and rattlesnake weed.
This is one of the unusual visitors ... I've never seen one before yesterday (7/27/21). It's a Bristle Fly. It's about the size of a bumblebee.
At least it's apparent where its name comes from.
A Four-Banded Stink Bug Hunter Wasp ... apparently it also like pollen.
Great Golden Digger Wasp
Great Black Digger Wasp
This apparently doesn't have a cool name other than of the thin waisted type (eremnophila aureonotata)
Besides the wasps and the BIG fly, there were a variety of bumblebees, honeybees and other smaller pollinators on the Rattlesnake Master flowers. I think this is Black and Gold.
This is a small insect with really unique antenna.
Continuing on antenna, this was a moth on our living room window. It was about an inch in length.
The blue coloration of this mosquito is distinctive; I couldn't find a name ... there are lots of mosquitos.
This Cat Bird apparently was trying to cool off; it was already a hot morning.
This little leaf hopper went well with this 'velcro' plant.
This Yellowthroat seemed to be watching the Rattlesnake visitors; possible thinking about lunch.