Category Archives: Photography

Chinese mantids eat monarch butterflies

This post is a PSA for anyone keen on helping monarchs: if you find Chinese mantids (Tenodera sinensis) in your yard, kill them. Below is a photograph of one that had just snagged a monarch visiting my swamp milkweed. The monarch is fine, by the way. After I intervened she flew off, then came back within seconds and resumed ovipositing.

Monarch butterfly captured by a Chinese mantid (Tenodera sinensi

But unless you’re observing your milkweed patch obsessively, you’ll probably never catch a Chinese mantid in the act. But you can infer their presence by piles of monarch wings (i.e., no body attached). No other animal does this to monarchs.

Monarch butterfly wings left by Chinese mantid predation

And caterpillars are just as susceptible. Here’s a Chinese mantid I interrupted just as it was about to strike:

Colin Purrington Photography: Insects &emdash; Chinese mantis with monarch caterpillar

Chinese mantis can be easily distinguished from any of the native mantids by the presence of a yellow dot in between the forelegs.

Chinese mantis (Tenodera sinensis)

If you find an ootheca (egg case) of this species, crush it. The oothecae have an irregular, messy surface that looks like a blob of brown, poorly-applied insulating foam. Oothecae of the native Carolina mantis are much smoother and streamlined (pic).

First-instar nymph of Chinese mantis (Tenodera sinensis) on ootheca

If you’re like most people (including myself), you grew up believing that mantids are a pesticide-free way of reducing garden pests. How could thousands of web sites be wrong?? The truth is, however, that Chinese mantids are so large that they tend to only eat large insects, and that usually means mainly butterflies, not aphids or other species that are tiny. So if you hate butterflies, by all means encourage Chinese mantids in your yard. But if you like butterflies in your garden, kill the Chinese mantids. And don’t just relocate them, even though that seems like the friendly, eco, green, peace-loving thing to do. Moving introduced, invasive species to another location simply facilitates further spread. It’s like transporting your rabid, aggressive pit bull to a different part of the city (“I didn’t want to euthanize it. Maybe it will thrive in a different neighborhood!”).

FYI, Chinese mantids also eat hummingbirds, plus other birds that are even bigger. The authors of that linked paper conclude,

“Our compilation suggests that praying mantises frequently prey on hummingbirds in gardens in North America; therefore, we suggest caution in use of large-sized mantids, particularly non-native mantids, in gardens for insect pest control.”

Italics mine.

End band net-wing beetle (Calopteron terminale)

This week I finally decided to teach myself how to identify Calopteron terminale (end band net-wing beetle), and the characteristics aren’t as bad as I thought. I made a visual to help in case others might find it useful:

Identifying End band net-wing (Calopteron terminale)

The easiest diagnostic feature is the transverse depression (dip), shown with a red line in photograph above. I think when I first noticed this depression in the wild I foolishly assumed it was a deformation that certain beetles got from being wedged into a pupal cases that were a tad too small for their bellies. But no, it’s a real, unique thing for this species. And no, I have know idea why they have it.

Below is another of my C. terminale photographs. In this one you can see that there’s a second, slight depression just anterior to the transverse band. For this reason many keys refer to an “undulation” along elytra rather than just a single depression. Here is one on Instagram that really shows the undulation. But sometimes the anterior one is hard to see.

Colin Purrington Photography: Insects &emdash; End band net-wing (Calopteron terminale)

Even the distal depression is sometimes hard to see with dorsal photographs, so in those cases use the uniformity in discal costae (ridge, vein) heights to make the ID. Excluding the edge vein there are four (4) ridges that are “elevated” to the same amount. Both C. reticulatum and C. discrepans (the other two members of the genus in the United States) have alternating ridge heights. The ridges are filled with poisonous hemolymph, by the way, so don’t poke them.

In addition to the above diagnostic features, many keys say that C. terminale has a “distinct blue tinge”. Other species in the genus sometimes have a blue tinge but I’ve only noticed a distinct blue tinge on C. terminale. 

For more information on identification, here are links to C. terminaleC. reticulatum and C. discrepans on BugGuide. If you’re on iNaturalist, here they are again: C. terminaleC. reticulatum and C. discrepansThere are many more (100+) species in the genus, and most of them are in South America, Central America, and Mexico. I’m not aware of a current guide to these other species but here’s an 1886 one for Central America.

If you encounter a mating pile of any of these insects, please take a lot of photographs and examine the abdomens of females for droplets of hemolymph. There are reports (Burke 1976) that males feed on this hemolymph. So if you get a good pic, send me a URL of the image so I can link to you.

For more natural history, start with these publications:

Burke, H.R. 1976. Observations on the adult behavior of the Lycid beetle Calopteron terminale (Coleoptera: Lycidae). Entomological News 87:229-232. 

McCabe, T.L., and L.M. Johnson. 1979. Larva of Calopteron terminale (Say) with additional notes on adult behavior (Coleoptera: Lycidae). Journal of the New York Entomological Society 87:283-288.

Augochlora pura foraging for pollen on maize

Last week I found hundreds of pure green Augochlora (Augochlora pura) foraging for pollen on Zea mays at Stroud Preserve in West Chester, Pennsylvania. Here’s my favorite capture, which shows a bee cutting open an anther with her mandibles.

Augochlora pura foraging for pollen on corn (Zea mays)

I was a tad surprised to see a wind-pollinated plant so mobbed with bees, but a later search of the internet suggested I shouldn’t have been. Even honey bees forage on corn, though the pollen is apparently not as desirable as other sources (e.g., Höcherl et al. 2011). This is also the reason why spraying a cornfield with insecticides can easily cause problems for any bees (and pollen wasps) that collect pollen.

This next photographs shows a better view of the scopa (modified hairs that hold the electrostatically-charged pollen) on the legs and abdomen. It also shows off how incredibly large corn pollen is (perhaps 85 microns, per some estimates, which is huge). Wind-pollinated plants with large pollen are odd.

Augochlora pura scopa with corn pollen

The final photograph shows some pollen grains set in motion by the foraging bee. The odd look (line segments with bright dot in middle) are presumably caused by the flash freezing the fast-moving grains only in the middle of the exposure (1/200 of a second). I’m not exactly sure why the grains are bright. It could be because they are strongly backlit by sun, but it could be something related to how pollen grain exines bend light (they can cause a pollen corona on allergy-alert days). Someday it might be fun to get a rear-curtain flash configured to better capture such motion.

Pure Green Augochlora (Augochlora pura) collecting pollen from corn