I looked it up and you're right on. I never knew those existed, but if they'll pollinate flowers then the more the merrier.

Syrphid flies don't stash pollen on their hind legs.

I suspect it's one of the small native solitary bees that hobnob anonymously in gardens.

Jean is correct. This is a bee, not a syrphid fly.

its a solitary bee know as a leaf cutter bee by the striping on the back and the size, they are quite small. the striping matches this image perfectly on your bee.

https://www.youtube.com/channel/UC2rcUDHm64nbp6kDUpDeiTw

Nope, the OP's photo is not a leafcutter bee. Leafcutter bees (family Megachilidae) carry their pollen in special hairs underneath their abdomen. The OPs bee clearly has pollen carrying hairs on its legs. There are many kinds of bees that have hair bands on their abdomen.

There are something like 4,000 species of bees in the world and lots of them live on the North American Continent. All of them help with pollination and all of them can benefit from any efforts we make to improve habitat quality and availability, and decrease the use of chemical pesticides. Many of the solitary bees are more efficient than honey bees at pollinating, and they have no aggressive tendencies or stinging behavior, because they don't have a nest or colony to protect.

martha

There are 30,000 species of bee in the world, as a very conservative estimate. There are around 4,000 in the US alone.

Oops. I mis-remembered what the 4000 referred to. I was clearly being far too conservative.

Nope, the OP's photo is not a leafcutter bee

NOPE,...I'm seeing this also as a leaf cutter bee, clearly showing pollen on the abdomen, of course a little on their hairy legs also, this bee has NO pollen basket.

Konrad, perhaps you are looking at the leaf cutter bee that theitaliangardenonyoutube posted. The OP's photo of the bee on the sunflower is just not a leaf cutter bee -- the photo is a dorsal view so you can't even see the underside of the abdomen (where a leaf cutter bee would have scopal hairs), but you can see the scopae on the hind legs that are completely full of pollen, which indicates it is not a leaf cutter bee.

i have seen them here in my yard also here in NC. i agree in the picture they do NOT have pollen baskets but they do have pollen on their legs which make it look like they are using their legs to transport pollen but this appears to be overflow from all the pollen they are storing on the underside of their abdomen.

i don't think its a 'Megachilidae - Leaf-cutter Bees, Mason Bees, and allies'.

i would say this is a 'Halictidae' or more commonly 'Sweat Bees'. i would bet 'Halictus tripartitus' or maybe 'Genus Halictus', google it and come to your own conclusion, im not a expert yet ;)