Black banded bee fly - Hemipenthes morio

I photographed this interesting insect in Cypress Hills, Alberta, in July, 2025.

Bee flies are a group of insects that are both good and bad, depending on what part of their development is referred to.  The adults visit flowers obtaining nectar and are pollinators.  However, the larvae are considered parasitic as they live in the brood chamber of solitary bees and consume the food stored for the young Hymenopteran.  In the end, the bee fly larvae kills the hosts through predation after the food supply has been exhausted.  They can adversely affect the population of important pollinators.

I thought this Dipteran was a tachinid fly due to the hairy abdomen.  I searched for an identification for the insect to no avail.  It wasn't until I uploaded my image to Google Lens that an ID came back, and not for a tachinid as I supposed.  It was identified as a black banded bee fly to my surprise.

Both tachinids and bee flies are members of the order Diptera- flies.  They are also both parasitoids, organisms that are parasites of another species but eventually end up killing the host.  The difference is that tachinids are typically beneficial because their hosts are often garden pests while bee flies kill an important group of pollinators.

I photographed this insect with my Zfc camera, 105 mm Z macro lens, and a macro ring flash.  I cropped the original image and am including it below - you can see the detail on the abdomen and wings better.  I only got the one photograph; bee flies are notoriously hard to get good shots of as they are fast and take to the wing quickly with little provocation.

A cropped view of the black banded bee fly.

Thanks for reading.   

Eric Svendsen     www.ericspix.com