The rush milkweeds are flowering.
The open flowers attract an array of insects.
For example, tarantula hawks seem to prefer milkweed flowers. In fact, they are one of the chief pollinators of the plant.
No surprise that rover ants also visit.
From the swollen appearance of the metasoma of the upper ant, it looks like the worker ants are feeding on nectar.
Wait, the nectaries aren't open on these buds.
It can be hard to think of something as small as a rover ant as a predator, but they do catch insects like this thrips.
The tarantula hawks, on the other hand, probably aren't in any danger.