A striking mallow caterpillar

Tarache delecta ("mallow caterpillar") on Hibiscus lasiocarpus | Hickman Co., Kentucky

Tarache delecta (“mallow caterpillar”) on Hibiscus lasiocarpus | Hickman Co., Kentucky

Last month while searching stands of Hibiscus lasiocarpus (hairy rose mallow) in western Kentucky, I encountered this rather large caterpillar feeding on the foliage. I presumed that something as large and striking in appearance as this should be a cinch to identify by scanning through photos on BugGuide, and not surprisingly I found photographs (here, here and here) of two very similar looking caterpillars from Oklahoma posted by Charles Schurch Lewallen. None of the photos, however, had an identification associated with them other than subfamily Acontiinae (family Noctuidae). The contributor mentioned in one of the photos that he had found nothing similar in the Wagner (2005) “bible” (a book that I do not yet own but hope to soon). Armed with this scant information (but definitive knowledge of its host plant), I searched Noctuidae of North America and settled on Tarache delecta as a good possibility. According to that site, T. delecta is the only member of the Acontiinae that feeds on plants in the genus Hibiscus. The site references Crumb (1956) for a larval description, but more useful was a plate of black & white photos that I found in Weiss (1919) and that seemed to be a good match for the species I had photographed. Weiss (1919) refers to the larva as the “mallow caterpillar” and notes that full grown larvae are 34–36 mm in length and dark purple with black spots edged with orange—consistent with the caterpillar shown here.

Apparently this species has been considered a pest of ornamental mallows. Weiss (1919) notes that the larvae feed on the upper and lower leaf surfaces usually near the margins, making large holes in the leaves and sometime devouring parts of the bracts around the buds. I will also note that, in recommending control of the caterpillars, he states that “there does not seem to be any reason why spraying with arsenate of lead should not be successful.” My, how times have changed!


Crumb, S. E. 1956. The larvae of the Phalaenidae. U. S. Department of Agriculture, Technical Bulletin 1135, 356 pp. + 10 plates [Google Books].

Wagner, D. L. 2005. Caterpillars of Eastern North America: A Guide to Identification and Natural History. Princeton University Press, Princeton, New Jersey, 512 pp. [Amazon].

Weiss, H. B. 1919. The more important insect enemies of the rose-mallow in New Jersey. New Jersey Department of Agriculture, Bureau of Statistics and Inspection Circular 25, 9 pp. + 4 plates [Google Books].

© Ted C. MacRae 2014

Posted in Lepidoptera, Noctuidae | Tagged , , , , , , , , | Leave a comment

Not quite adult

For the past few years I’ve had research plots in northwestern Tennessee. Each summer, once a month or so, I make the 5-hour drive to the site and spend the afternoon taking data. Any normal person would then check in to their hotel room in town, watch television, and make the drive back to St. Louis the next morning. Of course—I’m not normal, I’m an entomologist! The southeastern lowlands of Missouri, where over the years I’ve found (and continue to find) a number of good spots for collecting insects, are tantalizing close. Instead of retiring immediately to my hotel room, I’d rather head back to the lowlands and find a good spot for setting up a blacklight. It might be midnight before I finally get to a hotel room, but it’s all worth it. Some of the most interesting insects that I’ve featured here during the past few years have come to blacklights on one of these trips, including the primitive longhorned beetles Parandra glabra and Mallodon dasystomus and adult male bagworms, Thyridopteryx ephemeraeformis.

Subadult female, poss. Maccaffertium sp. | Mississippi Co., Missouri

Subadult female mayfly (prob. Maccaffertium sp.) | Mississippi Co., Missouri

Most of the spots I’ve found are located along the Mississippi River, a downside of which is the overwhelming abundance of aquatic insects that are often attracted to the lights. Caddisflies (order Trichoptera) are the worst, sometimes swarming the lights with such frenetic abundance that to check the sheets one must button the collar, hold the breath, dash in quickly to look at the sheet, and retreat just as quickly lest the fluttering hordes find their way up the nostrils, down the ear canals, and into the eyes. Mayflies (order Ephemeroptera) also can be attracted in great numbers, although they tend to be, fortunately, much calmer and better behaved on the sheet than their trichopteran counterparts. Normally, I pay little attention to these insects other than what is required to avoid breathing them—their abundance almost makes them unnoticeable. On one particular night in early August, however, my eyes caught the soft glow of a ghostly-white insect sitting on the underside of a leaf some yards away from the light. I looked closer to see it was a mayfly, and so pale was its coloration that I knew it would make for a striking photograph against the black night sky.

The reason for its milky-white coloration is due to a unique aspect of mayfly developmental biology—they are the only insects to develop fully functional wings before their final molt to adulthood. This stage, called the sub-adult or subimago, emerges from the water where it spent the past year as a nymph (also called a naiad) and flies to nearby vegetation, but it is still not mature. One additional molt is required, wings and all, before the insect finally reaches adulthood and can spend the few remaining hours of its life in single-minded pursuit of a mate. Sub-adult mayflies are distinguished from their adult counterparts by their paler coloration and opaque rather than clear wings. We can also tell that this individual is a female because no claspers are visible at the tip of the abdomen (which males possess for mating) and its relatively small eyes (the eyes of males almost completely cover their head).

My thanks to Dr. Robert Sites, who initially suggested this might be a species in the family Heptageniidae, and to Roger Rohrbeck for confirming my subsequent identification as probably belonging to the genus Maccaffertium.

© Ted C. MacRae 2014

Posted in Ephemeroptera | Tagged , , , , | 3 Comments

First-ever BitB “Reader’s Poll”

For seven years now I’ve been conducting this experiment called Beetles in the Bush. In that time I’ve written nearly 1,000 posts (with the help of a few guest authors), posted nearly 3,000 images, contributed or entertained over 10,000 comments, and watched the site creep ever closer to its millionth hit! This might leave you wondering why I should, now, be asking readers to provide feedback on why they visit BitB and what they like most (or least) about it. The reason is simple—blogging is less popular now than it was a few years ago. Comments and readership are both in decline (not just here, but across the platform), and the trend has left few clues about who the remaining readership is and what they are interested in. If I know clearly what readers want, it will be easier for me to provide it. That is not to say I expect (or even could) drastically change my content or its focus. However, if I know a certain topic is more popular than others I can give that topic priority, or if nobody really reads the “long-reads” I can skip them altogether. I hope you’ll indulge my curiosity by participating in the five short polls below that need only a few anonymous clicks of the mouse—no written responses required. Of course, if you wish to provide written feedback in the comments section it will be most appreciated. And, as always, thank you for your readership.

© Ted C. MacRae 2014

Posted in [No taxon] | Tagged , | 9 Comments

One-shot Wednesday: swamp milkweed leaf beetle

Labidomera clivicollis on Asclepias incarnata | Hickman Co., Kentucky

Labidomera clivicollis on Asclepias incarnata | Hickman Co., Kentucky

Technically this photograph of Labidomera clivicollis (swamp milkweed leaf beetle) doesn’t qualify as a “one-shot”, as I did take a few other shots as well. However, this was the only shot out of the handful that I didn’t throw away. It’s not perfect—the right front and left rear legs are raised awkwardly, and the lighting is a bit harsh. However, the important parts of the beetle are in focus, the composition is acceptable (with all parts of the beetle within the frame), and there is pleasing value contrast between the orange and black body of the beetle, the green plant on which it sits, and the clear blue sky in the background. The plant’s flowers have even added a smidgen of pink. All of the other photos lacked either focus or composition, neither of which are easily “fixable” in post-processing. The difficulty in getting a better photo is a result of the beetle’s refusal to settle down and stop walking and my lack of desire to spend an inordinate amount of time waiting for this to happen as opposed to finding the insect I was really looking for (more on that in a future post).

I found this beetle on swamp milkweed (Asclepias incarnata) in Hickman Co., Kentucky. As the common name suggests, swamp milkweed is one of the main hosts for this rather large beetle (at least, by leaf beetle standards). However, they can and do feed and develop on other milkweeds, especially common milkweed (A. syriaca), and even related genera such as swallow-wort (Cynanchum) and twinevine (Funastrum) (all belonging the family Asclepiadaceae).

Labidomera clivicollis is part of the orange and black milkweed mimicry complex, which includes monarch butterfly (Danaus plexippus), red milkweed beetles (Tetraopes spp.), large milkweed bug (Oncopeltus fasciatus), small milkweed bug (Lygaeus kalmii), milkweed assassin bug (Zelus longipes), and others. Most of these insects have evolved mechanisms for avoiding or detoxifying cardenolides (produced by milkweed as a defense against herbivores) and sequestering them within their bodies for their own defense against predators. This represents a classic example of a Müllerian mimicry ring, in which multiple insect species—sometimes from different families and even different orders—share a common warning color. Predators learn to avoid these colors and, thus, avoid all of the species within the mimicry ring.

© Ted C. MacRae 2014

Posted in Chrysomelidae, Coleoptera | Tagged , , , , , , , , , | Leave a comment

My, what busy palps you have!

In mid- to late summer, the swamps of southeast Missouri and adjacent areas along the Mississippi River become awash in color as stands of hairy rose mallow (Hibiscus lasiocarpus) put forth their conspicuous, white and pink blooms. I’ve been waiting for the mallows to bloom this year, as there is one particular beetle associated with plants in this genus that I have been keen to photograph since I first picked up a real camera a few years ago, to this point without success. My first attempt this year came in early August as I noted the tell-tale blooms while passing through extreme western Kentucky. I was foiled again (but would succeed the next day—more on this in a future post), but as I tiptoed over the soggy ground searching through the lush foliage, I saw a small, brightly colored cricket with curiously enlarged mouthparts. Even more interesting was the constant, almost frenetic manner in which the insect was moving these mouthparts. My first attempts to detach the leaf on which it was moving spooked it, and it jumped to another leaf, but I persisted and finally succeeded in detaching the leaf with the critter still upon it and maneuvering it up towards the sky for a few photographs.

Phyllopalpus pulchellus (red-headed bush cricket) | Hickman Co., Kentucky

Phyllopalpus pulchellus (red-headed bush cricket or “handsome trig”) | Hickman Co., Kentucky

It didn’t take long to identify the cricket as Phyllopalpus pulchellus, or “red-headed bush cricket” (family Gryllidae). This species, also known as the “handsome trig” on account of its stunning appearance and membership in the subfamily Trigonidiinae, is distinctive among all North American orthopterans by its red head and thorax, pale legs, dark wings, and—as already noted—highly modified maxillary palpi with the greatly expanded and paddle-like terminal segment. According to Capinera et al. (2004), adults appear during mid- to late summer near streams and marshes on vegetation about one meter above the ground—precisely as this individual was found. Surely it represents one of our most photographed cricket species (208 BugGuide photos and counting).

The greatly expanded palps are thought to mimic beetle mandibles or spider pedipalps.

The greatly expanded palps are said to mimic beetle mandibles or spider pedipalps.

The obvious question to anyone who sees this species is, “Why the curiously enlarged palps?” Both males and females exhibit this character (even as juveniles), so it seems clear that there is no special sexual or hypersensory function. One idea mentioned on BugGuide (perhaps originating from this EOL post by Patrick Coin) suggests that the crickets are Batesian mimics of chemically-defended ground beetles (family Carabidae) such as bombardier beetles (genus Brachinus). This thought is based on their similar coloration, the convex and shiny (and, thus, beetle-like) forewings of the females, and some resemblance of the enlarged palpi to the mandibles of the beetles. I am not completely satisfied with this idea, since bombardier beetles are generally found on the ground rather than foliage. Moreover, males lack the convex, shiny forewings exhibited by females, and resemblance of the palps to beetle mandibles doesn’t explain their curiously constant movement (ground beetles don’t constantly move their mandibles). Another idea suggested by orthopterist (and insect macrophotographer extraordinaire!) Piotr Naskrecki is a mimetic association with another group of arthropods, noting that the busy movements of the palps is very similar to the way jumping spiders (family Salticidae) move their pedipalps. This suggestion also is not completely satisfying, as it leaves one wondering why the crickets are so boldly and conspicuously colored. While some jumping spiders are brightly colored, I’m not aware of any in eastern North America with similar coloration (indeed, many jumping spiders can be considered ‘drab’). Perhaps the crickets have adopted mimetic strategies using multiple models in their efforts to avoid predation?

The brown wings and long, sickle-shaped ovipositor identify this individual as a female.

The brown wings and sickle-shaped ovipositor identify this individual as a female.

The individual in these photos can be identified as a female due to the presence of the sickle-shaped ovipositor and, as mentioned above, the convex, shiny forewings. Males possess more typically cricket-like forewings, perhaps constrained to such shape by the sound producing function they must serve. The males do, however, exhibit an interesting dimorphism of the forewings, with one wing being clear and the other one black. Fellow St. Louisan and singing insect enthusiast James C. Trager notes this dimorphism has been mentioned in the literature but not explained and suggests it may have something to do with the adaptive physics of sound production.

Congratulations to Ben Coulter, who wins Super Crop Challenge #16, which featured a cropped close-up of the enlarged maxillary palpi of this insect. His 12 pts increase his lead in the overall standings for BitB Challenge Session #7 to an almost insurmountable 59 pts. Morgan Jackson and Troy Bartlett round out the podium with 10 and 9 pts, respectively—Troy’s points being enough to move him into 2nd place in the overalls with 23 pts. Third place in the overalls is still up for grabs, since none of the people occupying the 3rd through 6th places has played for awhile—realistically any number of people behind them could jump onto the podium (or even grab 2nd place!) in the next (and probably last) Session #7 challenge.


Capinera, J. L., R. D. Scott & T. J. Walker. 2004. Field Guide To Grasshoppers, Katydids, And Crickets Of The United States. Cornell University Press, Ithaca, New York, 249 pp. [Amazon].

© Ted C. MacRae 2014

Posted in Gryllidae, Orthoptera | Tagged , , , , , , , , , | 6 Comments

Super Crop Challenge #16

Who am I?

Who am I?

Can you identify the structures in the photo above (2 pts), their significance (2 pts), and the organism to which it belongs (order, family, genus, and species—2 pts each)? Comments will be held in moderation so everybody has a chance to participate, but there are early-bird bonus points on offer for those who get their answers in quickest. You’ve got the weekend to think about it. :)

p.s. Read the full rules for details on how (and how not) to earn points. Good luck!

© Ted C. MacRae 2014

Posted in [No taxon] | Tagged , | 7 Comments

Southern armyworm feeding on soybean

Southern armyworm (Spodoptera eridania) late-instar larva feeding on soybean.

Southern armyworm (Spodoptera eridania) late-instar larva feeding on soybean.

Here is another animated gif that I made recently, this one showing a late-instar larva of southern armyworm (Spodoptera eridania) feeding on soybean (Glycine max). This polyphagous species is widely distributed from the southern U.S. through the northern half of South America and feeds on a variety of weeds, especially pigweed (Amaranthus spp.) and pokeweed (Phytolacca americana). It also occasionally attacks vegetable, fruit, and ornamental crops; however, in recent years it has become increasingly important on cultivated soybean in Brazil and Argentina, especially in regions where cotton is also cultivated. As a result, they have become one of the insects that I deal with regularly in my own research. More information on this and other armyworm species that affect soybean can be found in my earlier post, Quick Guide to Armyworms on Soybean.

Like many other lepidopteran caterpillars that feed on foliage, late-instar larvae become “feeding machines” that remain active both day and night as they try to cram as much nutrition into their expanding bag of a body as possible in preparation for an adult life focused solely on finding mates and laying eggs. Large larvae actively feeding during the day can be rather conspicuous, and as a result they often secrete themselves on the undersides of the leaves while feeding to make themselves less visible to predators. As they feed, however, a “window” opens up that gradually eliminates their cover. Rather than remaining in the same spot and feeding until they are completely exposed, however, larvae will move when the feeding hole reaches a certain size and find another place to conceal themselves before resuming feeding. Different caterpillar species have different exposure tolerances, and as a result, this combines with slight differences also in preferred tissue types to create recognizable differences in the damage patterns resulting from feeding by different species.

For those interested, making these animated gifs is really simple and allows those of us without expensive macro-video gear to simulate short videos of insect behavior. I make my animated gifs at GIFMaker.me—all you do is take a series of photos, touch them up in photo editing software (I use Photoshop Elements to adjust levels, color and sharpness), upload them to the site in the sequence desired, and click “Create Now”. It couldn’t be easier! You don’t even need a “real” camera—I took the photos for this gif with my iPhone using the “burst” function to take a rapid sequence of photos (all you do is hold your finger down on the shutter button for the desired length of time).

© Ted C. MacRae

Posted in Lepidoptera, Noctuidae | Tagged , , , , , | 4 Comments