Readers’ wildlife photos

Bring out your photos! I have a fair few, but always worry that they’ll run out. Today’s contributor is Mark Sturtevant, whose notes and IDs are indented:

This batch finishes the queue of pictures of arthropods from two years ago.

It is not unusual in this hobby to discover much later that I had taken pictures of something with an interesting backstory. In the first picture, we see a rather gangly looking male spider that strongly resembles an orb weaver. I had assumed that was what it was. But notice that it is eating a jumping spider, which is no small feat. Also, look at those especially prominent spines along its legs. This is a species of pirate spider, probably Mimetus notius, and these spiders are specialist predators on other spiders. They will even take a spider in its own web by luring the owner to investigate evidence of captured prey, and then disabling it with a very fast acting venom.

Next is an odd looking caterpillar that is new to me. This is Heterocampa obliqua, which belongs in the Prominent moth family. Many caterpillars in this group have rear pro-legs that are artfully extended in order to merge their profile into a leaf. I found it only by inspecting hundreds of leaves along a forest trail. This is one of the best methods of finding things that would otherwise be overlooked.

The onset of autumn is always a bummer, but one highlight is that there is drama under the apple trees in our back yard. At this time the squirrels open up many of the wind-fallen apples, and this attracts insects. Among the most abundant visitors are yellowjackets, and these are entertaining since fights can break out among them as one wasp decides to take ownership of an entire apple. The result is what I like to call an “epic wasp battle.”

The first two pictures show two species. The one on the left is the Eastern yellowjacketVespula maculifrons, and the one on the right is the German yellowjacketVespula germanica. The latter species was introduced to the U.S. in the 1960’s and it is displacing native species. They did have a skirmish, which I managed to somewhat capture.

The third picture shows a more substantial contest, but this one was between two V. germanica wasps. The loser usually just flies away to find a different apple, although sometimes they go at it repeatedly. No injuries result from these encounters as far as I have seen, so the above name, epic wasp battle, is really just an exaggeration for the fun of it.

During one outing at a park, I ventured much too far off the trail and became fairly lost in the woods for a time. But it was still worth it because I came across this female scorpionfly (Panorpa) feeding on bird poo. Scorpionflies are odd looking insects, and they are carnivores, but that probably means they do most of their feeding on dead insects. This bird dropping must have contained some delicious yum-yums since the scorpionfly completely ignored me as it spent several minutes energetically probing into it. She eventually dragged out the carcass of a rove beetle.

The Magic Field that I often describe here has its seasonal specials. Late in the season, the finely powdered soil is marked by many traces of arthropods, including ant lion pits, entrances to the burrows of solitary bees, wasps, and wolf spiders, and the meandering indented trails left by the ‘chonky’ insect in the last picture. This is a female ‘oil’ blister beetle (Meloe impressus), and she is indeed impressively heavy with eggs. She will lay those eggs in the ground, and the hatched larvae have their own rather amazing backstory. This includes ‘hypermetamorphosis’, where the larvae pass through several distinctly different larval stages. But even more remarkable is the way in which the murderous larvae begin their lives, as explained in this terrific video. I am still geeking out about it.

10 Comments

  1. Posted July 1, 2020 at 7:57 am | Permalink

    Fascinating stuff, great shots as always, particularly the scorpionfly. It is a very odd looking thing.

  2. boudiccadylis
    Posted July 1, 2020 at 8:30 am | Permalink

    I watched the beetle video. Those larvae are definitely awesome in their ability to move about so effectively. It also makes me wonder why we aren’t plagued by great numbers of them.
    As usual I learn much from your photos. Thank you.

    • Posted July 1, 2020 at 11:12 am | Permalink

      What an amazing life history!! I wonder what the intermediate steps in the evolution of this behavior would be. Does anyone know what the life-histories of its close relatives are like? These might give a clue about the ancestral behaviors from which this evolved.

  3. Ken Kukec
    Posted July 1, 2020 at 8:36 am | Permalink

    … one highlight is that there is drama under the apple trees in our back yard. At this time the squirrels open up many of the wind-fallen apples, and this attracts insects. Among the most abundant visitors are yellowjackets, and these are entertaining since fights can break out among them as one wasp decides to take ownership of an entire apple.

  4. rickflick
    Posted July 1, 2020 at 10:48 am | Permalink

    “I am still geeking out about it”.

    Me too. I imagine this kind of positive reinforcement was the driving force behind much of scientific progress. I can imagine Galileo, Newton and Einstein geeking out over their own discoveries. It’s a great feeling almost anyone can share.

  5. Mark R.
    Posted July 1, 2020 at 3:39 pm | Permalink

    Another great set of photos Mark. Thanks for the video of those blister beetle larvae. Amazing…it reinforces my belief that being an insect would be a rough existence.

  6. Posted July 1, 2020 at 5:37 pm | Permalink

    Brilliant. I wonder what the later larval stages of the blister beetle look like.

  7. tjeales
    Posted July 1, 2020 at 7:49 pm | Permalink

    Absolutely wonderful stuff. Every one very interesting. I hope to see a scorpion fly one day. There are apparently a couple of species in Tasmania. Great to see a northern hemisphere Pirate Spider, we have our own here mostly in the Austromimetus genus. Very similar looking. Thanks for sharing these

  8. Posted July 1, 2020 at 8:18 pm | Permalink

    Thanks, Mark! These are wonderfully informative. I’m amazed by how you figured out what the female scorpionfly was doing.


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