Best of BitB 2012

Welcome to the 5th Annual “Best of BitB”, where I pick my favorite photographs from the past year. 2012 was one of the most intensive travel years I’ve ever had—I spent 8 weeks in Argentina from February through April, made separate trips to Puerto Rico and Arkansas in May (bracketing a personal week in California), traveled almost weekly to Illinois and Tennessee from June to September (interrupted by a personal week in Florida in July), toured the southeastern U.S. (Arkansas, Louisiana, Mississippi and Georgia—great food!) in early September, chased tiger beetles in Oklahoma, Texas and Arkansas in late September, went back to Argentina for a week in October, and capped off the travel year by attending the Entomological Society of America Annual Meetings in Knoxville, Tennessee (for the first time in more than 10 years!)—whew! While many would cringe at such a travel load, I am among the lucky few who actually get paid for doing something that is also my hobby—entomology! This gives me ample opportunity to further hone my photography skills (nine of the 13 photos I’ve selected below were actually taken while I was on business travel), resulting in two key accomplishments this year—my first ever photography talk at the ESA’s insect photography symposium and my first commercial sales (look for the BitB commercial site to go online in 2013).

Enough blather! Here are my favorite BitB photographs from 2012. Click the link in the text below the photo to see the original post. I would greatly appreciate knowing if you have a favorite (and why)—your feedback will be enormously helpful to me as I continue to learn and develop as a photographer.  For those interested, here are my previous year picks for 2008, 2009, 2010 and 2011. And, as always, thank you for your readership!

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Spintherophyta (?) sp. in flower of Abutilon pauciflorum | Buenos Aires, Argentina

From Pollen Bath (posted 2 Feb). One of my 2012 learnings was that sometimes a photograph that is not so close is more effective than one that is as close as possible. In one of my earlier attempts at “not-so-close” macrophotgraphy, the soft colors of the flower compliment the brash shininess of the tiny leaf beetle that has been feeding on its pollen. Pink lines lead the eye directly to the subject and create a pleasing composition, and pollen grains stuck to the beetle—a distraction in some situations—add to the miniature natural history story of the photo.

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Apiomerus flavipennis with stink bug prey and kleptoparasitic flies | Chaco Province, Argentina

From Lord of the flies! (posted 11 Mar). I selected this photo solely for the complex natural history story drama it shows—stink bug (Piezodorus guildenii) feeding on soybean becomes prey of an assassin bug (Apiomerus flavipennis), with volatiles from the chemicals it emitted in a vain attempt to defend itself serving as cues to kleptoparasitic flies (families Milichiidae and Chloropidae) that benefit from the assassin bug’s labors.

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Planthopper nymph | Buenos Aires Province, Argentina

From Seeing the unseen (posted 26 Mar). Another learning that I began putting into practice in 2012 was the use of low perspective for compositional impact. The cryptic coloration of this planthopper nymph (family Fulgoridae) made it almost invisible on the branch on which it was sitting when viewed from a normal “top-down” human perspective. Getting “down under” it, however, brought the nymph to life and emphasized its unusual form.

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Megabaris quadriguttatus | Corrientes Province, Argentina

From I fear no weevil (posted 12 Apr). I spent much of 2012 working on the “blue sky background” technique, with these weevils from northern Argentina representing one of my better attempts. Macrophotography of insects with a blue sky background involves setting exposure, ISO, and aperture to achieve two separate exposures—full flash illumination of the subject for maximum depth-of-field, and ambient light from the sky to create a clean, uncluttered, natural-looking background. In this shot I managed to achieve an almost ideal shade of blue to compliment the wild black, white and red colors of the beetles. (My one criticism of the photo is having clipped one of the beetle’s feet.)

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Bombylius sp. cf. mexicanus | Scott Co., Missouri

From One-shot Wednesday: Upside-down bee fly (posted 16 May). This photo is unusual if nothing else. Focus, lighting, depth-of-field, and composition are all better than can be hoped for in a single shot, but the subject—perfectly alive—is in a most unusual position. Read the original post to find out how this happened.

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Perisphaerus sp. (a pill roach) | Vietnam (captive individual)

From Holy conglobulation, Batman! (posted 27 May). White-box photography is an excellent technique for clean, uncluttered photographs of insects, but it also isolates them from their natural surroundings and limits their natural history appeal. The best white-box photos are those that highlight a key feature or behavior of the subject—in this case a pill roach’s comically conglobulating defensive posture.

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Micronaspis floridana (Florida intertidal firefly) larva | Pinellas Co., Florida

From Even a 12-year old can discover the larva of a rare, endemic species! (posted 31 July). Here is another photo whose back story played a big part in its selection. This firefly larva not only represents a rare Florida-endemic species but was also first seen by my then 12-year old nephew, who willingly accompanied me through a dark, spooky salt marsh in the middle of a humid Florida night to see what he could learn. The lesson here for budding natural historians (and old-timers like me) cannot be overstated!

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Arctosa littoralis (beach wolf spider) | Lewis Co., Missouri

From ID Challenge #20 (posted 23 Aug—prelude to Ghosts in the night posted 28 Aug). Those who follow this blog know of my obsession with close-up portraits, and while tiger beetles are the subjects I most commonly photograph in this manner, I am always on the lookout for good subjects in other taxa. This wolf spider “face” almost looks human, with “two” eyes, two “nostrils” and a shiny upper lip above huge (albeit hairy) buck teeth! It’s enough fill-the-frame spidery goodness to melt (or explode) the heart of even the most ardent arachnophobe!

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Anticarsia gemmatalis (velvetbean caterpillar) egg on soybean leaf

From Life at 8X—Guide to lepidopteran eggs on soybean (posted 3 Sep). “Life at 8X” was a new series I introduced this year, featuring insects photographed at magnifications testing the upper limit of my equipment and photographic skills. Diffraction is the chief difficulty with magnifications as high as this and is the primary flaw in the above photograph. Nevertheless, such view of a moth egg on the underside of a soybean leaf provides a spectacular view of the otherwise unseen micro-world that lives right beneath our noses.

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Megacyllene decora (amorpha borer) on snakeroot flowers | Mississippi Co., Missouri

From A classic fall ‘bycid (posted 12 Sep). This second example of “blue sky background” was taken later in the year and was considerably more difficult to capture than the first because of the larger size of the subject and resulting need for a longer focal length macro lens. Getting a well-lit, focused, and composed image with a desirable shade of blue in the background depended not only on finding the proper camera settings, but also secure body and camera bracing techniques for this completely hand-held shot.

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Cicindelidia politula politula (Limestone Tiger Beetle) | Montague Co., Texas

From Photographing the Limestone Tiger Beetle (posted 28 Sep). I will go ahead and say it—this is my favorite photograph of 2012. As discussed under the first entry, panning back from the subject can allow for some very interesting compositions. This photo combines charismatic pose by a wary subject with panning back and low perspective to create an image that scores high in both natural history and aesthetic appeal.

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Calosoma sayi (black caterpillar hunter) | New Madrid Co., Missouri

From Black is beautiful! (posted 7 Nov). Of course, close-as-possible can also be used to create striking photos, especially if the subject exhibits features that are best seen up close. Anything with jaws fits the bill in my book, and highlighting the mandibular sculpturing of this caterpillar hunter (a type of ground beetle) required precise angling of the flash heads for maximum effect.

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Cicindela repanda (Bronze Tiger Beetle) | St. Louis Co., Missouri

From Persistence Pays (12 Nov). This final selection is not a rare species, but it is as close as I have come to what I consider the “perfect” tiger beetle macrophotograph—a close, low angle, lateral profile of an adult in full-stilt posture (a thermoregulatory behavior), well lit, perfectly focused, and with a dynamic but pleasingly blurred background. It’s a perfect storm of a photo that took the better part of two hours to achieve—rarely do all of these elements come together in a hand-held photograph of an unconfined tiger beetle in its native habitat.

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Well, there you have it. I hope you’ve enjoyed my selections, and again please do let me know if you have a personal favorite. See you in 2013!

Copyright © Ted C. MacRae 2012

Shooting 8X hand-held in the field

Just to prove it can be done, here is an uncropped photograph of the seed weevil Althaeus hibisci (or the closely related A. folkertsi) (order Coleoptera, family Chrysomelidae, subfamily Bruchinae). Adults of these species measure only 1.5–2.5 mm in length (Kingsolver 2004), yet this individual almost completely fills the frame:

Althaeus hibisci/folkertsi on Hibiscus moscheutos lasiocarpus | Route 66 State Park, St. Louis Co., Missouri

I achieved 8X magnification by stacking 68 mm of extension tubes under my Canon MP-E 65mm 1–5X macro lens and extending the bellows of the lens out to its maximum. Shooting 8X is not for the timid—the small subject to lens distance complicates lighting (full flash required), and even finding the subject in the viewfinder can be next to impossible. However, doing it hand-held in the field requires more than just courage and patience—good bracing techniques to minimize movement by and between the camera and the subject are essential. Here is how I do it:

• I sit down, prop my knees up, and rest the camera in the crotch between my knees (the camera quickly becomes very heavy since it’s being held by only one hand—see next bullet) while positioning it near my face. If possible, I lean back against something as well to provide even more stability, although this is often not possible depending on field conditions.
• I hold the leaf or flower supporting the subject in my left hand. Subjects this small are rarely going anywhere (or if they are skittish then I use the same slow, deliberate techniques that I use with larger skittish insects), so it is possible to hold the leaf or flower and position the subject right in front of the lens. Hand holding the subject’s support also affords the ability to micro-adjust the position and angle of the subject for optimum composition or to adjust for movement by the subject (easier than trying to track it by moving the lens). In this case of the photo featured here, I detached the leaf with the beetle from the plant (use small scissors to snip the leaf petiole, as this avoids the “jolt” that happens if you try to pick the leaf and which usually results in the subject fleeing). In other cases, I leave the leaf attached and carefully “pull” it towards me to hold it steady.
• I look through the viewfinder and brace my left wrist (yes, the same hand that is holding the subject) on the underside of the lens, then slowly move the subject towards the lens with my fingers until I see movement and can micro-adjust for proper focus. Bracing your wrist against the lens is key—it is nearly impossible to hold the subject steady in front of the lens without bracing your wrist against it. In effect, this “fixes” the subject to the lens. Also, before I begin looking for the subject through the viewfinder I study its position on the leaf and look for “landmarks” that I can recognize when looking through the viewfinder to minimize the time needed to find the subject (the more time you spend looking for the subject, the greater the chance it will move or flee). Again, the subject to lens distance is very small, but with practice you’ll get a feel for precisely how far from the lens you need to place the subject.
• I hold my breath and micro-adjust the subject position to nail the focus (usually on the eye) and then fire a shot. If it takes too long to get the focus I exhale and try again, as body shake will only get worse once it starts. Important: After taking the first shot, do not move the hand holding the subject as you look at the image preview and/or histogram—the first shot rarely has the settings precisely where you need them, and keeping the subject in place prevents a lot of re-searching after making the needed setting adjustments with the right hand.

Other than lighting, nailing the focus is the most difficult aspect of shooting hand-held at such high magnifications. The more relaxed and stable you can keep the rest of your body, the less hand movement you’ll experience while holding the subject and the greater chance you have of hitting the focus. Again, a fully extended MP-E lens on 68 mm of extension tubes becomes very heavy very quickly when held in one hand (even when resting on your knees), so expect your forearm muscles to give out quickly until you have a chance to strengthen them through practice.

I use these same techniques to some degree at lower magnifications as well—certainly for anything above 2X. I’m interested in doing a lot more 8X photography, however, because there is a whole world of tiny insects that are not being photographed due to their very small size. These insects are no less fascinating and beautiful than their larger, more oft photographed brethren.

Finally, you might be asking why I don’t just carry a tripod or collect subjects and bring them back to the studio for more controlled conditions. There are many photographers who advocate the use of tripods, but I’m not one of them. I am first and foremost an entomologist, and when I’m in the field I’m generally already carrying at least a net and other equipment for collecting insects. There are opportunity costs involved if I also try to lug a heavy tripod with me. What’s that? I could leave it in the car and then go get it when I need it? Honestly, I would pass on a lot of shots if I had to go back to the car to get something for it. The same goes for studio photography—there are many shots I would simply pass on if getting them meant that I needed to collect subjects, keep them in good condition for the duration of the trip (which might be days or more), and then setup in a studio. Moreover, there are many shots—specifically regarding behavior—that would be impossible with collected subjects. But really, it has mostly to do with what I want to be and portray as an insect photographer, and that is somebody who has the ability to photograph unconfined subjects exhibiting natural behaviors in their native habitats. Having the ability to shoot 8X hand-held in the field if I want to gives me more options and makes me a better photographer.

Do you have any special bracing or stabilizing techniques that you use for high-mag hand-held macrophotography? If so I’d love to hear about them.

REFERENCE:

Kingsolver, J. M. 2004. Handbook of the Bruchidae of the United States and Canada. U.S. Department of Agriculture, Technical Bulletin 1912, 2 volumes, 536 pp.

 

Copyright © Ted C. MacRae 2012

Working with Cerceris fumipennis—Epilogue

Cerceris fumipennis nest littered with Neochlamisus sp. beetles

In Working with Cerceris fumipennis Part 1 and Part 2, I talked about the use of this species as a biosurveillance tool for Buprestidae. These wasps are specialist predators of jewel beetles, which they capture almost exclusively and paralyze with their sting to use as food provisions for their offspring in underground nests. I also mentioned that there are other species of Cerceris, each specializing in its own distinct prey group, and at my site in east-central Missouri I found C. bicornis, a weevil specialist, almost as common as C. fumipennis. Thus, when I came upon this particular Cerceris wasp nest, I wondered it I had encountered yet another species in the genus, for littered around it were case-bearing leaf beetles in the genus Neochlamisus.

The bright coppery coloration suggests Neochlamisus platani

I counted 11 beetles lying on the diggings surrounding this nest, and as is typical with buprestids around C. fumipennis nests these beetles all appeared to represent the same species (I’ve done a little collecting of Neochlamisus beetles in Missouri—the especially bright coppery coloration suggests to me N. platani, a species found on eastern sycamore, Platanus occidentalis). I’ve also noted that C. fumipennis nests littered with beetles on the surface also have beetles—usually of the same species—freshly cached underground, so I decided to dig up the nest to see what might be in it. As I inserted the grass stem and started digging, I heard the distinctive buzzing indicating the wasp was still inside the nest, and when it appeared I noted the distinctive three yellow facial markings that identify it as a female C. fumipennis. As suspected, the nest contained another seven beetles of the same species, and I would later learn that C. fumipennis, while specializing on jewel beetles, does occasionally take other prey. Philip Careless and colleagues recorded two leaf beetles, including Neochlamisus bebbiana, and one weevil as hosts for this wasp at their Working with Cerceris fumipennis website. If my species ID of these beetles is confirmed, this should represent yet another non-buprestid host record for C. fumipennis, although I should also mention that out of several hundred observations this was the only non-buprestid prey I observed around or in a C. fumipennis nest.

Copyright © Ted C. MacRae 2012

Palmetto Tortoise Beetle, Hemisphaerota cyanea

Hemisphaerota cyanea (palmetto tortoise beetle) on saw palmetto (Serenoa repens)| Levy Co., Florida

While most leaf beetles (family Chrysomelidae) are found associated with herbaceous plant species, many members of the subfamily Hispinae—which includes leaf mining beetles and tortoise beetles—are found on the foliage of woody plants. In North America the most distinctive of tortoise beetles found on trees is the palmetto tortoise beetle, Hemisphaerota cyanea. These distinctive dark blue, hemispherical-shaped (hence, the genus name) beetles with yellow antennae are found in the deep southeastern U.S. on the fronds of saw palmetto, Serenoa repens, and other native and introduced palms. I found the beetles in these photographs near Cedar Key Scrub State Preserve in Levy Co., Florida while searching white sand 2-tracks through sand scrub habitat for the Florida-endemic Cicindelidia scabrosa (Scabrous Tiger Beetle).

Beetles scarify the leaf epidermis, leaving trough-like feeding marks.

I first saw this species during my first insect collecting trip to Florida back in 1986. I didn’t know much then (other than that I really, really enjoyed traveling to different parts of the county to collect insects!). I was in Everglades National Park (with a permit) when I first noticed them dotting saw palmetto fronds. I think I had actually noticed them for some time but thought they were some type of scale insect before eventually realizing it was actually not only a beetle, but a tortoise beetle (one of the many groups of insects in which I was interested during those early, formative days).

Specially modified tarsi and a hemispherical shape allow the beetle to clamp itself tightly against the leaf to repel attack by ants and other insect predators.

I also remember being struck by how difficult it was to pry the adults off of the leaves on which they were sitting. It turns out that these leaf beetles have specially modified tarsi with thousands of bristles tipped with adhesive pads on the undersides. Normally only a few of the pads contact the leaf surface, but when the beetle is threatened it clamps all of them against the leaf and secretes an oil that strengthens the adhesive capabilities of the pads. Thus secured, the beetle clamps its hemispherical-shaped body down tightly against the leaf and is able to resist the efforts of ants and other predators to pry it from the leaf.

Copyright © Ted C. MacRae 2012

Beetle botanists

Calligrapha spiraeae on Physocarpus opulifolius | Jefferson Co., Missouri

While Dicerca pugionata (family Buprestidae) is, for me, the most exciting beetle species that I’ve found in Missouri associated with ninebark (Physocarpus opulifolius). it is not the only one. The beetles in these photographs represent Calligrapha spiraeae, the ninebark leaf beetle (family Chrysomelidae). Unlike D. pugionata, however, I almost never fail to find C. spiraeae on ninebark, no matter when or where I look, and whereas D. pugionata has been recorded in the literature associated with a few other host plants like alder (Alnus spp.) and witch-hazel (Hamamelis virginiana), C. spiraeae is not known to utilize any other plant besides ninebark as its host.

Beetles in the genus Calligrapha are among the most host-specific of all phytophagous beetles, with most of the 38 species in this largely northeastern North American genus relying upon a single plant genus as hosts (Gómez-Zurita 2005). The genus as a whole is fairly recognizable by its dome-like shape and black and white or red coloration, with the black markings on the elytra varying from coalesced to completely broken into small spots. The species, however, are another matter, with several groups of species that are quite difficult to distinguish morphologically. Fortunately most of them can be easily distinguished by their host plant (although such information is rarely recorded on labels attached to museum specimens). Calligrapha spiraeae, for example, with its reddish coloration and small black spots, looks very much like two other species in the genus—C. rhoda and C. rowena. Those latter species, however, are restricted to hazel (Corylus spp.) and dogwood (Cornus spp.); as long as the host is known, the species can be readily identified in the field.

At this point you may be wondering why the species name refers to the plant genus Spiraea rather than Physocarpus. In fact, ninebark was already known as the host plant when Say (1826) described the species, but the name spiraeae was given because at the time ninebark was included in the genus Spiraea (Wheeler & Hoebeke 1979).

REFERENCE:

Gómez-Zurita, J. 2005. New distribution records and biogeography of Calligrapha species (leaf beetles), in North America (Coleoptera: Chrysomelidae, Chrysomelinae). Canadian Field-Naturalist 119(1): 88–100.

Say, T. 1826. Descriptions of new species of coleopterous insects of North America. Journal of the Academy of Natural Sciences of Philadelphia 5:293–304.

Wheeler, A. G., & E. R. Hoebeke. 1979. Biology and seasonal history of Calligrapha spiraeae (Say) (Coleoptera: Chrysomelidae), with descriptions of the immature stages. The Coleopterists Bulletin 33:257–267. 

Copyright © Ted C. MacRae 2012

A tortoise beetle gift

Chelymorpha varians | northwestern Buenos Aires Province, Argentina

A few days after returning from travel through northern Argentina, I found a jar on my desk with this beetle in it. One of my colleagues has seen it in the field while I was away and figured I would be interested in seeing it. Although I’m half-a-world away from home, I immediately thought of our North American species Chelymorpha cassidea when I saw it. Armed with this hunch, I typed “Chelymorpha Argentina” into Google, and the first result that came up was a paper by Hamity & Neder de Román (2008) about the species Chelymorpha varians in Argentina and its potential as a biocontrol agent for the widespread weed Convolvulus arvensis. Included in the paper was a plate showing variability of coloration and maculation in the adults, and my individual was a dead ringer for the species. Still, getting a species ID on the very first hit of the very first search attempt just seemed too easy, so I consulted the wonderfully comprehensive Cassidinae of the world – an interactive manual. This site, too, contained multiple images of Chelymorpha varians showing an extraordinary range of variability in color (from yellow to red) and degree of maculation (from immaculate to heavily maculated). A quick perusal of other species indicated as similar or also occurring in Argentina turned up nothing nearly as similar and convinced me that I had, indeed, arrived at a correct ID.

As the name suggests, markings are highly variable in shape and degree of development.

As indicated in the above cited paper, and like our own C. cassidea, species in the genus Chelymorpha are associated almost exclusively with plants in the genus Convolvulus. I would have preferred to photograph the beetle on foliage of this plant, but not knowing precisely where I might find it I decided to do white box instead. I got some printer paper and was looking for a cardboard box to line the inside with it when I spotted a styrofoam cooler of just the right size.

The scientific name translates literally to ''variable turtle-body''

These are okay white box photos, but I’ve decided if I want to do white box right I need to get a larger flash unit that is a little easier to work with off the camera. Right now I have only the small twin-flash heads from my MT-24EX—their small size makes them difficult to manipulate off the camera, and leaving them attached to their bracket limits the directions in which they can be oriented relative to the subject. As a result, I had to use more heavy-handed post-processing in these photos than I normally like to do in order to get the levels right. Hmm, I have a birthday coming up in about a month…

REFERENCE:

Hamity, V. C. & L. E. Neder de Román. 2008. Aspectos bioecológicos de Chelymorpha varians Blanchard (Coleoptera: Chrysomelidae, Cassidinae) defoliador de convolvuláceas. Idesia 26(2):69–73.

Copyright © Ted C. MacRae 2012

Pollen Bath

Spintherophyta (?) sp. in flower of Abutilon pauciflorum | Buenos Aires, Argentina

One of the smallest insects I saw during my latest visit to La Reserva Ecológica Costanera Sur (Buenos Aires, Argentina) was this tiny leaf beetle (family Chrysomelidae) feeding in the flower of a malvaceous plant that I take to be Abutilon pauciflorum. At only ~4 mm in length, it could have easily gone unnoticed had I not noticed there were several feeding in flowers in a small, localized area. The best I could come up with for an ID was subfamily Chrysomelinae due to their globular shape, although the small size didn’t seem right. Turns out I’d forgotten to consider the Eumolpinae, which also contains globular species that are usually much smaller than those in the Chrysomelinae, and according to leaf beetle specialists Shawn Clark and Ed Riley this is likely a member Spintherophyta or a closely related genus.

Covered with tasty, sticky pollen!

Although there are only four species of Spintherophyta in North America (Schultz 1976), and of those only S. globosa is widespread and commonly encountered, the diversity of the genus explodes in the Neotropics (Blackwelder 1946 lists 71 species). Accordingly, neither Shawn nor Ed were brave enough to venture a guess as to which species this might represent. I should probably defer to their good sense, but part of me wonders if that coppery pronotum might suggest S. cupricollis—one of only two species in the genus listed by Blackwelder (1946) for Argentina.

REFERENCE:

Blackwelder, R.E. 1946. Checklist of the coleopterous insects of Mexico, Central America, the West Indies, and South America. Bulletin of the U. S. National Museum 185:551-1492.

Schultz, W. T. 1976. Review of the genus Spintherophyta (Coleoptera: Chrysomelidae) in North America north of Mexico. Annals of the Entomological Society of America 69(5):877–881.

Copyright © Ted C. MacRae 2012

A Modest Model for Mimicry

Spring is still a long way off but it’s times like these that I draw on past experiences so I can continue to be thrilled by insect natural history even during the coldest of months.  In this case I am thinking back seven years ago to my first encounter with a warty leaf beetle.  These beetles are certainly unremarkable for their size or coloration but the “set-up” shot below attempts to illustrate what is amazing about warty leaf beetles.  Can you pick out the single individual warty leaf beetle (Exema sp.) among caterpillar frass (aka caterpillar poop)? 

Figure 1. Set-up shot with Exema sp. and caterpillar frass

If you had trouble finding the beetle in the above image then check out the next image and you’ll see the beetle has “sprouted” a head, legs, and antennae.

Figure 2. Set-up shot with Exema sp. and caterpillar frass

I don’t know what caught my eye the first time I encountered a warty leaf beetle on the foliage of a small shingle oak while exploring a woodland edge in Perry Co., MO.  It probably helped that it was one of the larger species of the genus Neochlamisus but it still only measured about 3-4 mm.  One thing I do remember about the encounter, though, is that there was something about it that made me do a double take.  My first thought was exactly what the beetle might have hoped, that it was caterpillar frass.  But this frass had legs (Figs. 3 and 4)!  I was at first incredulous but soon became enthralled as I beheld something that I had never noted while flipping through field guides.  I had once again stumbled across something that I would never have imagined—a beetle that mimics caterpillar poop!

Figure 3. Neochlamisus sp. on shingle oak

Figure 4. Neochlamisus from the perspective of a short distance away

The beetles in the tribe Chlamasini were apparently not at the table the day decisions were made on what model they would mimic.  These guys at best mimic small bits of debris but are dead ringers for the frass of lepidopteran larvae (i.e., caterpillars).  Then as if to add insult to injury, we dubbed the tribe the warty leaf beetles!  The Chlamasini may humbly mimic excreta but what they lack in a flashy model they make up for with absolutely superb mimicry.  The Chlamasini are remarkably similar to the frass of lepidopteran larvae in size, shape, texture, and color but the aspect that really completes the mimicry is that, upon disturbance, the head is retracted and the legs and antennae are neatly folded into precisely matched grooves leaving no indication that this was once a beetle (Figs. 5 and 6).  Even the finer details of coloration were not overlooked as some warty leaf beetle species are variably colored, including an almost metallic sheen in some places that closely resembles the coloration of some caterpillar frass.  In fact the mimicry of warty leaf beetles is so convincing that I recently dropped a piece of suspect frass in a vial in hopes that it might sprout legs and represent a new species of warty leaf beetle for me.

Figure 5. Exema sp. with appendages extended

Figure 6. Exema sp. with appendages retracted

If the disturbance is sufficient to cause the beetle to completely retract these appendages, they will likely roll off the leaf and fall out of harms way.  Though these beetles can be relatively common, occurring even in my suburban St. Louis yard, the small size [Exema is only 2-3 mm (Figs. 7 and 8) while Neochlamisus is slightly larger at 3-4 mm] and resemblance to something unremarkable ensures that these beetles often times go unnoticed.  When I have happened to notice these beetles I found Neochlamisus associated with shingle oak, Quercus imbricaria, and Exema associated with Asteraceae, including gray-headed coneflower, Ratibida pinnata, and sweet coneflower, Rudbeckia subtomentosa.

Figure 7. Exema sp. on sweet coneflower, Rudbeckia subtomentosa

Figure 8. Exema sp. ready for flight

The Chlamasini are in the subfamily Cryptocephalinae within the leaf beetle family (Chrysomelidae).  The Chlamisini can be found worldwide but are most diverse in the Neotropics.   We have 6 genera in North America, two of which are shown here.  Interestingly, the excreta theme doesn’t stop at frass-mimicry.  Like other members of Crytocephalinae, warty leaf beetle larvae are “case-bearing”; that is they are housed in a case which in this instance is made out of… you guessed it, their own feces (Fig. 9).  You would think that most moms would frown on such a practices but mothers in the Cryptocephalinae actually instigate the practice when they equip each egg laid with a cap of feces that serves as starting material for the case and likely also serves to dissuade would be predators.

Figure 9. Chlamasini larva, likely that of Exema sp. on sweet coneflower, Rudbeckia subtomentosa

My experiences with Neoclamisus seven years ago captures perfectly why I am so drawn to explore for insects— there is always something new to find and every once in a while something comes out of the wood work that is beyond what I could have imagined.

REFERENCE:

Lourdes Chamorro-Lacayo, M. & A. Konstantinov. 2009. Synopsis of warty leaf beetle genera of the world (Coleoptera, Chrysomelidae, Cryptocephalinae, Chlamisini). ZooKeys 8:63–88.

Copyright © Chris Brown 2012