Just look at all that pollen that this Summer Long-horned female has groomed into its scopa on its hind legs. Yes, all that bright yellow on its legs is pollen.
I can't tell if this is a Melissodes robustior or Svastra obliqua expurgata.
But I know that this is a Summer Long-horned because it has a flattened head (as opposed to rounded head).
And it is a female because the antennae aren't as long as on a Long-horned male (see image below).
Also, you can identify the females quite easily because, since they focus on collecting pollen, they are the ones with bright pollen loads on their hind legs.
These bees often visit sunflowers and cosmos plants, which is one of the reasons I plant both Delta sunflowers and various cosmos plants every year.
I just love to observe them in the garden, a true sign of summer.
Here is a Summer Long-horned male on one of the Delta sunflowers.
You can see why they have the common name "long-horned bee".