Entomologist Dr. Art Evans and VPM radio producer Steve Clark discuss hummingbird moths and bumblebee moths. Art notes the occasional challenges of proper insect identification.
Steve Clark: I'm Steve Clark with Dr. Art Evans, entomologist, and this is What’s Bugging You.
Art Evans: Have you ever seen one of these?
Clark: Is it a hummingbird moth?
Evans: It's a dayflying hawkmoth, that's for sure, and we have two species here. There's the hummingbird moth and the ghastly-named snowberry clearwing. But everybody I know calls it a bumblebee moth, because they look like bumblebees as they're hovering around during the day unfurling that long proboscis like a straw and sucking up nectar.
Clark: But they're bigger than a bumblebee.
Evans: Well, they're bigger than a bumblebee, that's for sure. One of my challenges was to try and photograph one as it was hovering over flowers. I wanted to get a nice picture of it when its proboscis was deep into the flower, and I forgot that I had gotten a fairly decent photograph of one almost 10 years ago, and I thought, “Oh, I'll have to post this up on my Facebook page.” And I identified it as the hummingbird moth, Hemaris thysbe. One of my friends showed up on Facebook shortly thereafter and said, “Uh, I think it's the snowberry clearwing, Hemaris diffinis.” [laughing] With his assistance we discovered together what the differences are that separate these two moths. I did not fully appreciate just how variable both species are, and I got caught out. So I'm glad somebody stepped up and pointed out the error of my ways. And now I know the difference between the two species.
Clark: I don't see these anywhere. Maybe I've seen one, but it’s been a long time.
Evans: Actually I've seen quite a few when I'm out and about. I was at Three Lakes Park a few weeks ago, and they were all over the flowers. In our neighborhood, I've seen them on the butterfly bush, which is a non-native Asian plant that's very popular with people who want to attract butterflies to their gardens. So they are certainly around. And the first year that we planted our native honeysuckle in our yard, we had the caterpillars of the snowberry clearwing all over it. At first I thought the angle at which I had shot the moth was not good enough to definitively identify it, but it turns out it was the perfect angle. It was a side shot, and you can clearly see in the snowberry clearwing that it has a dark bar on the side of its head that crosses its eye and extends downward along the thorax, and the hummingbird moth doesn't have that at all. And of course there are other differences too, but this is one of the distinctive field marks if you see it at the right angle.
Clark: And it’s the clearwing what?
Evans: Snowberry clearwing. You're just making my point for me. Thank you very much. I don't know where that name came up, and it's got to be the dumbest common name I've ever heard. It looks like a bumblebee. People refer to them as bumblebees. The problem is that when people see either one of these dayflying moths, they call them indiscriminately hummingbird moths or bumblebee moths. They're, they're not interchangeable. They're two different kinds. But what I was reminded of here is sometimes how difficult it is to identify insects, and that you really have to pay special attention to characters. It's always better to have a specimen in hand. Of course, I never collected that specimen. It's gone in the ether. It's a challenge, and I really do appreciate it when people say, “Hey, Dr. Evans, would you take a second look at that?” [laughing] Thank you for that correction.
Clark: Dr. Art Evans is a research associate at the Virginia Museum of Natural History. You’ll find photos and audio, links to the museum and Art’s Facebook page at vpm.org/bugs.
Dr. Arthur V. Evans teams up with VPM Radio producer Steve Clark for a weekly feature, “What’s Bugging You?,” which airs during NPR’s Morning Edition. The program takes its name from another of Evans’ books “What’s Bugging You – A Fond Look at the Animals We Love to Hate.”
Tune in each Tuesday at 8:45 a.m. or at 5:44 p.m. on VPM News