Readers’ wildlife photos

Today we’re graced with another dollop of photos by Mark Sturtevant, whose IDs and notes are indented. As usual, he thoughtfully provided links as well. Note two cases of mimicry: a bird-dropping mimic and a moth that looks just like a wasp.

For some years, various posts online from people who monitor dragonfly and damselfly populations have been reporting that the largest damselfly in the continental U.S. was moving north, probably as a result of climate change. This is the ‘great spreadwing’ (Archilestes grandis). Certainly big by damselfly standards, as can be seen in the linked picture. I had seen a description where a robust population of them could be found in a certain park in Ann Arbor, MI., and that was only an hour away from me! So I planned, mapped, and waited for late summer, which is great spreadwing season. The park was lovely, and many interesting insects live there. So here are pictures that were taken from various visits, and it includes great spreadwings.

Near the main entrance is a large community garden, and on a patch of cultivated dill was a lovely black swallowtail caterpillar (Papillio polyxenes). This was evidently preparing to form a chrysalis.

Nearby was a big tobacco hornworm caterpillar (Manduca sexta) that was not so lucky. Readers can surmise what is going on with the poor thing. This species is very similar to the tomato hornworm, but one difference are the markings on the larva.

Next is a red-spotted purple butterfly chrysalis (Limenitis arthemis). It appears to be a bird-dropping mimic.

Along the paths were bushes, and on their leaves were beautiful crickets sitting out in the open. This is the red-headed bush cricket (Phyllopalpus pulchellus), and I have since learned that they too are making their way northward. Note the enlarged palps, which they regularly wave around. Perhaps this is to signal to each other.

Grasshoppers are always a favorite subject because they just look weird somehow. Perhaps the most unremarkable of species is the differential grasshopper (Melanoplus differentialis), but even these plain-as-dirt insects are worth a good long look.

A creek runs through the woods, and this is where the damselflies would be breeding. As I approached the woods for the first time, I was in a tremendous state of nerdy excitement. It was immediately clear that the main reason for being there was not going to present a great challenge because right on a branch overlooking the entrance to the woods sat a beautiful male great spreadwing! All back-lit and glorious. Surely, the good lord was rewarding me for my righteousness!

I have since taken many pictures of this immigrant. But for now the next pictures show a female, and then another male. They were numerous and pretty easy to photograph with a long lens. Probably one reason why they have been successful at colonizing new territory is that this species is very tolerant of marginal conditions. They are known to happily breed in road ditches, for example.

Finally, here is an insect that I certainly don’t’ recall photographing before. This moth, known as the raspberry crown borer (Pennisetia marginata), is an excellent mimic of a yellowjacket wasp. Of course it is widely viewed that mimicry of bees and wasps is a way to gain protection against predators like birds, and there is presumably some truth to that. But a while ago Jerry had posted an interesting paper that suggests that mimicry of stinging insects is to avoid predation by social wasps like hornets, paper wasps, and yellow jackets. You see, these social insects are constantly in search for insect meat to feed their larvae, but they generally don’t try to tackle stinging insects.

16 Comments

  1. Posted June 10, 2020 at 9:14 am | Permalink

    Wonderful photographs as always Mark. Couldn’t get a sense of how big the large damselfly is, but it is lovely like all of its kin.

    • Posted June 10, 2020 at 9:23 am | Permalink

      Thank you. Hard to find a picture that really does it. Th wingspan is 3 inches according to Wikipedia. Definitely larger than any other damselfly in the u.s., and one definitely sees them as big in real life. Even a bit ponderous in flight.

      • Posted June 10, 2020 at 9:40 am | Permalink

        That is big. The damselflies I see in my neck of the woods (Seattle) are not particularly big, but beautiful. Iridescent Familiar Bluets. I suppose they are common everywhere.

      • Posted June 10, 2020 at 10:03 am | Permalink

        Wonderful photos as always. I never knew there were such colorful crickets!

        You would really enjoy seeing the helicopter damselflies we have here. About eight+ inches wingspan!!

        • Posted June 10, 2020 at 10:45 am | Permalink

          I know! I have a friend here who had one land on them. Extraordinary.

  2. mallardbrad
    Posted June 10, 2020 at 9:39 am | Permalink

    Terrific photographs; excellent information to digest. Thank you for sharing!

  3. Jacques Hausser
    Posted June 10, 2020 at 10:11 am | Permalink

    Nice and informative photos as usual. Giving a quick and careless first look at the bushcricket,I thought “ah, a small Carabid”. The pale color of the hind legs camouflage them and contribute to this first impression. Could it be a case of mimicry too? Beetle are hard stuff and frequently stinky too…

    • Posted June 10, 2020 at 10:49 am | Permalink

      That seems a good idea. There are carabids with a similar color scheme, along with ‘fire beetles’, which are common beetles that are also chemically protected: https://bugguide.net/node/view/679390
      Like those, the crickets sit right out in the open on top of leaves. Very un-cricket-like, really. So your idea seems very possible.

  4. boudiccadylis
    Posted June 10, 2020 at 10:31 am | Permalink

    As usual great photos. I have never been particularly interested in bugs, not afraid of them, just that they all seemed to be more or less alike. You’ve definitely piqued my interest and curiosity. Thank you. Nice to learn something new.

  5. EdwardM
    Posted June 10, 2020 at 10:34 am | Permalink

    Thanks again, Mark and I hope you will continue to contribute your photos.

  6. rickflick
    Posted June 10, 2020 at 11:30 am | Permalink

    Wonderful. I love to zoom in on these pics and stare them in the eye. I like the blue eye of the second spreadwing best.

  7. Jenny Haniver
    Posted June 10, 2020 at 1:40 pm | Permalink

    Re the red-spotted purple butterfly, I see that the caterpillars also resemble bird shit, albeit ambulatory; and the adults resemble poisonous pipe-vine swallowtails. A trifecta of mimicry. Wonder why the caterpillar doesn’t resemble that of the pipe-vine swallowtail, which screams “noli me tangere!”

    • Posted June 10, 2020 at 3:15 pm | Permalink

      I suppose that selection for mimicry / camouflage / deception are independent choices for larva, pupa, and adult.

  8. tjeales
    Posted June 10, 2020 at 4:54 pm | Permalink

    Lovely photos. The colour and texture of that first caterpillar is very pleasing to me. That cricket is also very striking and the horrific images of parasitism. A wonderful set.

  9. Posted June 10, 2020 at 5:26 pm | Permalink

    These are brilliant, as usual. The raspberry crown borer moth made a nice try (so to speak) with those antennae, but they’re still a dead giveaway. Same with the eyes and thorax. Guess it’s good enough to fool a wasp.

    If those moths really eat raspberries, though, I think I’ll root for the wasps to penetrate the disguise.

  10. Posted June 10, 2020 at 8:06 pm | Permalink

    You must be a damselfly whisperer, Mark, the uncanny way you get them to sit still for you! Excellent work once again. Thanks!


%d bloggers like this: