Readers’ wildlife photos

September 29, 2020 • 7:45 am

Keep those photos coming in!  Today’s contribution is from a regular, Mark Sturtevant, who sends us a panoply of insects (and one arachnid). His notes are indented:

Here are pictures of insects that were taken during the previous summer.

The first pictures are of carpenter ants (looks like Camponotus pennsylvanicus) tending a colony of poplar tree aphids (Chaitophorus populicola). I think it is well known that ants can guard aphids, and feed on the sugary secretions that they supply in return. In the second picture you can see an ant give food to another.

In the next picture is the familiar monarch caterpillar (Danaus plexippus) on milkweed. Besides the bright colors that advertise their toxicity, the paired tendrils on each end is a deception so that predators may doesn’t know which end is the head.

On the campus where I used to work (now I teach online), there are cherry trees which always have dozens of large bagworms, which are caterpillars that form a protective bag that is about two inches long. So I brought a few home and put them on our cherry tree for pictures. These odd caterpillars never leave their bag entirely as they move around clumsily along the twigs and leaves of their food plant. You can see some fresh silk in the pictures. They quickly make a security tether in case they need to retreat into their bag, and eventually they will build on this tether to make a stout strap of silk that holds them firmly in place. To move to a different location, they must first chew thru their tether. The species is Thyridopteryx ephemeraeformis, or ‘evergreen bagworm‘, which means they will also feed on conifers. When photographing them, if I sat for a time they would soon emerge and start crawling along a twig. But any disturbance would cause all of them to immediately retreat into their shelters. One wonders how they poop in there.

Bagworms are weird in other ways. They pupate in the bag, and the males emerge as about the plainest, drabbest moths in all of existence. I have never seen one. Adult females don’t emerge from the bag, as they are wingless and legless and rather maggot-like. Males find them through pheromones. After mating, the female lays an egg mass in her bag, and then dies. The pictures in the link above show the strange adults.

Next is a tiny moth. This is Mathildana newmanella. It is a member of the ‘concealer moth’ family, where larvae stay hidden in leaf rolls or in woven bundles of plant debris. Note the ‘Trumpian’ wig.

It’s time to dip into the long queue of Odonate pictures. Here are a pair of amber spreadwing damselflies (Lestes eurinis). I somehow have never noticed these before, even though they become exceedingly common along certain woodland trails. The male shown in the first picture is positively luminous, but the female is also quite lovely. Amber spreadwings develop slightly tinted wings as they mature.

‘Bluet” damselflies are among the most challenging group to identify because there are so dang many species, and many look very much alike. I have a couple of online acquaintances who can identify them in an instant, but I have yet to get the hang of it. In any case, after much lip biting and stress, I suggest that the first bluet damselfly here is a male azure bluet (Enallagma aspersum) [at least I am sure it’s a male], and the second, which is a real eye-popper, looks to be a male northern bluet (Enallagma annexum). Y’all should double click on that one.

Finally, I always check myself for ticks after an outing, and sometimes one or two manage to take a ride home with me. They are almost always American dog ticksDermacentor variablis, a tick that accepts a wide range of mammalian hosts. The color pattern informs us that this one is a male. Males take only a brief blood meal. One thing I had learned recently, which makes ticks even weirder, is that they have eyes that are a bit larger than expected. You can see one here as the pale circular spot just above the base of the second leg. Of course, after pictures were taken, this little guy took a ride down the loo.

19 thoughts on “Readers’ wildlife photos

  1. Always nice to see some nice photos of insects, our overlooked overlords.
    I found a monarch crawling along my milkweed yesterday. With nights in the low 50’s, days in the mid 70’s, and the milkweed turning brown, I was surprised to see it this late in the year. Seems unlikely it will have time or temperature to finish eating, make a chrysalis, do it’s presto-change-o and be on it’s way to Mexico in time.

  2. Nice photos, and a good look at a tick. Recommend some repellent for those trips. Something with deet or picaridin maybe. If you get any photos of chiggers I’d like to see that. The worst bug on the planet I believe. Never see them but you sure feel them after.

  3. Excellent photos and commentary, as always.

    I got into dragonflies and damselflies this past summer. Bluets are one of the reasons I decided to put damselflies on the back burner and concentrate only on dragonflies for the time being (too many nearly identical species of bluets).

    I see that this particular tick is not a good carrier of Lyme disease but that it can carry other scary bacteria. Ticks have amazing life cycles but I find them hard beasties to like!

  4. Some real eye candy here. Never seen a bagworm…interesting critter. Tick…yuck. Too bad there isn’t a human equivalent to “sentinel”. Take a tab orally once a month and no ticks or fleas.

  5. Terrific photos as always Mark. The ant photos in particular came out very well and as you’ve noted before are difficult fast moving subjects. Nice tick pic too 🙂

  6. The bagworms, Psychidae, are certainly a very odd group. Another psychid, Acanthopsyche atra apparently has a particularly unusual ability that could play a role in the dispersal of its larvae. Heath and Emmet’s ‘Moths and Butterflies of Great Britain and Ireland’ (vol 2) cites a paper by Jorgensen (1954) which states that adult females are rather similar in appearance to dipterous larvae and a number of these were observed falling from their cases to the ground after pairing. Eleven of these were fed to a captive European robin whose droppings over the next 24 hours were retained. Between 30 and 40 larvae subsequently hatched from these droppings, made cases and started to feed!

    I do not know if anyone has subsequently been able to show that this potential mechanism for dispersal plays any significant role in the ecology of the species.

    Jorgensen P L (1954) Larver af Acanthopsyche atra L. klaekket af fugleekskrementer. Flora Fauna , Silkeborg 1954: 122 -127 (quoted in Hoffmeyer S (1970) Dispersal of Pachythelia species (Lep. Psychidae) Entomologist’s Rec. J . Var. 82: 33)

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