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

A belated Happy Birthday

It seems that November 24th came and went without me even realizing that BitB turned six years old that day! Six years—wow, has it really been that long? I guess forgetting birthdays officially puts me in the old-timer camp (both as a person and as a blogger). No fanfare or celebration. Instead, I blithely wrote my 778th post (Q: How do you photograph cactus beetles?) and carried on as usual.

I guess it’s too late now to make a big deal of it, but I will make the observation that November 2013, with its 15 posts, was one of my heaviest blogging months ever (the most since 18 posts in December 2012 and the overall high of 21 in April 2010). This may come as a surprise to those who have heard me grouse periodically about the decline of blogging, both of my blog in particular and as a platform in general. It’s a different world than it was when I started BitB—Twitter and Facebook have taken over much of the social interaction that used to take place on blogs, relegating the latter primarily to satisfying a small but persistent niche demand for long-content. Throughout the course of these changes, however, motivation to blog still comes to me consistently and often. Mostly it seems to be an internal need to express myself, but the occasional and very much appreciated feedback in the form of comments and emails also helps. So, with that, thank you for the past six years, and here’s looking at the next six!

Enough blather—here are a few colorful net-winged beetles in the genus Calopteron (family Lycidae) to help with the celebration. They were photographed in northern Argentina (Chaco Province) in April 2012 while visiting flowers of Chilean goldenrod (Solidago chilensis). I’m not sure if they represent more than one species, as the taxonomy of the genus in the Neotropics appears to be very poorly known at this time—if so it would seem there exists in this area a mimicry complex that is ripe for study.

Calopteron sp. on flowers of Solidago chilensis| Chaco Province, Argentina

Calopteron sp. on flowers of Solidago chilensis | Chaco Province, Argentina

Calopteron sp. on flowers of Solidago chilensis| Chaco Province, Argentina

Calopteron sp. on flowers of Solidago chilensis | Chaco Province, Argentina

Calopteron sp. on flowers of Solidago chilensis| Chaco Province, Argentina

Calopteron sp. on flowers of Solidago chilensis | Chaco Province, Argentina

Copyright © Ted C. MacRae 2013

Red-eyed poop!

I was looking at some of my older files and ran across these photographs taken in early 2011 in Campinas (São Paulo state), Brazil. They’re not my best photos from a compositional and technical perspective, as I was still on the steep part of the learning curve with the Canon MP-E 65mm macro lens. This lens is no doubt powerful and allows amazingly close-up photographs, but it is rather a beast to learn in the field, especially hand-held. I could quibble endlessly about missed focus and suboptimal composition with these shots, and that is probably why they never made it to the front of the line for being posted. Nevertheless, they still depict some interesting natural history by one of nature’s most famous natural history poster children—the treehoppers (order Hemiptera; family Membracidae).

An adult next to a cast nymphal exuvia.

Bolbonota sp. (Hemiptera: Membracidae), upper right | Campinas, São Paulo, Brazil. Note cast exuvia.

The treehoppers shown in these photos were found on a low shrub in a municipal park and are all that I could manage before my clumsy, unpracticed molestations caused the few adults and nymphs present in the aggregation to disperse. The dark coloration of the adult and its globular form, corrugated pronotal surface, and lack of any horns identify the species as a member of the genus Bolbonota in the New World tribe Membracini (another similar genus, Bolbonotoides, occurs as a single species in Mexico). Species identification, however, is much more difficult, as there are at least a dozen species recorded from Brazil and perhaps many more awaiting description. We have a similar though slightly more elongate species here in eastern North America, Tylopelta americana. I don’t know if this is a specific character or not, but I don’t recall seeing any members of this genus with smoldering red eyes—it gives them an almost devilish appearance, especially the blackish adults (see last photo)!

Bolbonota sp. late-instar nymphs clustered together.

Bolbonota and similar genera are often cited by evolutionists as examples of insects that mimic seeds. I can see such a resemblance if I force myself, but honestly I don’t really buy it. To me they seem to bear an uncanny resemblance to the chlamisine leaf beetles which are thought to mimic caterpillar frass. As with the beetles they resemble, frass-mimicry seems to make much more sense than seed-mimicry, especially given their preference for positioning themselves along the stems of the plants on which they feed (when was the last time you saw seeds of a plant randomly distributed along its stems?). Another thought I’ve had is that this is not an example of mimicry at all, but merely an accidental consequence of the heavy, corrugated body form they have adopted, which likely also affords them a reasonable amount of protection from predation. Confounding both of these theories, however, are the radically different appearance and form of the adults versus the nymphs, and indeed even between the different nymphal instars (see early- and late-instar nymphs in photo below). The later instars seem perfectly colored for mimicking unopened leaf buds, but why they would start out dark in early instars before turning mottled/streaked-white as they mature, only to revert back to dark when reaching adulthood, is a mystery to me. If my thoughts are anywhere close to the truth, it would be a remarkable case of different life stages mimicking the products of two different taxonomic kingdoms (plant parts as nymphs, animal poop as adults)!

Bolbonota sp. nymphs tended by Camponotus sp. | Campinas, São Paulo, Brazil.

An ant (presumably Camponotus sp.) tends a first-instar nymph alongside a later instar.

Of course, if either/both of these lines of defense fail then there are the ant associates that often protect treehoppers and other sap-sucking, aggregating insect species in exchange for the sweet, sugary honeydew that such insects exude as a result of their sap-feeding habits. I presume this ant belongs to the genus Camponotus, perhaps C. rufipes or C. crassus which are both commonly encountered treehopper associates in southern Brazil. I have written previously about ant-treehopper mutualism in the stunningly-marked nymphs of another treehopper, Guayaquila xiphias, and its ant-associate C. crassus in Brazil Bugs #15 – Formiga-membracídeos mutualismo (a post that has become one of this blog’s most popular all-time). Maybe this post will never match that one in popularity, but I do find the third photo shown here remarkable in that is shows no less than five elements of this treehopper’s natural history (early-instar nymph, late-instar nymph, cast nymphal exuvia, partial adult, and an ant-associate) within a single frame (shot by a person still on the steep portion of the MP-E 65mm learning curve!).

Copyright © Ted C. MacRae 2013

North America’s itsiest bitsiest longhorned beetle

Longhorned beetles (family Cerambycidae) are generally regarded as medium to large-sized beetles, but that doesn’t mean the family is without its pip-squeeks! There are a number of species, primarily in the tribes Tillomorphini, Anaglyptini, and Clytini (all in the subfamily Cerambycinae) that are remarkably effective mimics of ants. Some of these, especially members of the genus Euderces, are quite small, but none are smaller than the absolutely diminutive Cyrtinus pygmaeus. Measuring only 2–3 millimeters in length, the adult beetles can be found on dead twigs and branches among equally small ants such as Lasius americanus.

Cyrtinus pygmaeus | Stoddard Co., Missouri

Cyrtinus pygmaeus | Stoddard Co., Missouri

The species is said to be widespread across eastern North America, having been recorded on a number of hardwood trees (Lingafelter 2007). I have no reason to doubt this, having reared a number of individuals from dead branches of river birch (Betula nigra), chinquapin oak (Quercus muhlenbergii), willow oak (Q. phellos) and black oak (Q. velutina) (MacRae & Rice 2007), but in the wild I have only encountered the species three times—each time as a single specimen that I noticed crawling on my arm after a bout of beating a variety of dead branches. The most recent occasion was two weekends ago during a visit to the Mississippi Lowlands of southeastern Missouri. I had done a bit of beating in a forest dominated by black oak, blackjack oak (Q. marilandica), and southern red oak (Q. falcata) and not found much when I felt a “tickle” on my right forearm. I looked down and was just about to flick the “ant” off my arm when something about the way it moved gave me pause. I stopped and looked closer, then recognizing what it was, instinctively called out “Oh cool, Cryrtinus pygmaeus!” My field partners for the day had never seen the species, so I let them look before I placed it in a vial. I was sure they would ogle at the incredibly tiny longhorned beetle, but their subdued “Hmm”s makes me think they were less impressed with the find than I was.

Cyrtinus pygmaeus

Like other ant-mimicking genera, the elytra of this species bear two prominent humps near their bases.

If the species is so common, why have I not seen them more commonly or on the beating sheet proper as soon as I beat them from their host plant? The answer, I believe, is that they are such effective mimics of the tiniest of ants that I simply overlook them! The series of specimens retrieved from my rearing cans could not be missed, as I combed through the contents every week during the beetle emergence period to make sure I found anything—longhorned beetle or otherwise—that emerged from the wood inside. In the field, however, my search image is queued for more “normal-sized” beetles and especially movement. Most other ant-mimicking longhorned beetles, even though they look very much like ants, still run like longhorned beetles—swiftly, almost frenetically, looking for the earliest opportunity to spread their elytra and take wing. Cyrtinus pygmaeus, on the other hand, is slow and clumsy, not a runner at all (slower even than the ants they mimic). If the three individuals I’ve encountered in the wild to date hadn’t happened to fall on my arm rather than the beating sheet and gotten stuck in my hair and perspiration I may never have noticed them.

Cyrtinus pygmaeus

Bands of white pubescence on the bases of the elytra give the illusion of a narrow-waisted ant.

I considered putting the beetle on a branch for photographs as soon as I found it, but since I had already pulled it off my arm I had already lost the chance to take true field photographs. Instead, I placed the beetle live in a vial and photographed it the next day at home. All of the photos were taken hand-held with an MP-E 65 mm macro lens at the upper end of its magnification capabilities. The green background is simply a colored file folder placed about four inches behind the beetle as I photographed it.

p.s. can you tell me what unusual feature this particular individual exhibits?


Lingafelter, S. W. 2007. Illustrated Key to the Longhorned Woodboring Beetles of the Eastern United States. Coleopterists Society Miscellaneous Publications, Special Publication No. 3, 206 pp.

MacRae, T. C. and M. E. Rice. 2007. Distributional and biological observations on North American Cerambycidae (Coleoptera). The Coleopterists Bulletin 61(2): 227–263.

Copyright © Ted C. MacRae 2013

The “silky-bellied humpbacked” ant

Last year during my extended work stay in Argentina, I was able to slip away from my duties during the first week of April and spend some time in the city of Corrientes in the northeastern part of the country. The city is one of my favorites in Argentina, but what I love most about it is its convenience as a base camp for exploring some of the habitats in the Grand Chaco ecoregion of northern Argentina. One day I had a chance to visit Chaco National Park about 100 km northwest of the city, site of some of the last remnants of the great quebracho forests that once covered much of northern Argentina. The forest preserved at Chaco NP takes its name from the quebracho colorado chaqueño (Schinopsis balansae) trees that dominate it, standing in defiant contrast to the vast, hot sea of cotton fields and mesquite fence-rows that surrounds it. While hiking a trail through the heart of the forest, I looked down to see a most impressive ant crawling across the forest floor:

Camponotus sericeiventris

Camponotus sericeiventris | Chaco National Park, Argentina

Because of its black color and the striking, silky sheen of the abdomen, I was immediately reminded of the Camponotus mus ants that I had photographed a year earlier further south in Buenos Aires. However, this fellow (er, fella…) was considerably larger than that species, and looking at the photographs later I was also struck by the acute spines at the humeral angles of the pronotum (in C. mus the humeral angles were obtuse) and the flattened legs. All of this combined to make it one of the most handsome ants that I had ever seen! I posted the above photo on my Facebook page asking for ID help, and James Trager quickly responded that the ant represents Camponotus sericeiventris, which translates roughly to “silky-bellied humpbacked” ant. Now there’s a common name I can get behind.

Camponotus sericeiventris

Of course, it turns out that I could have easily determined the species on my own using the characters I had already noted—primarily the acute spines. Googling “camponotus acute spines” retrieves as its first result a paper by Wheeler (1931) that discusses this ant and a newly discovered (at the time) cerambycid beetle, Eplophorus velutinus [now Euderces velutinus] mimicking the ant (Fisher 1931). As soon as I read Wheeler’s first paragraph I knew I had the right species:

Camponotus (Myrmepomis) sericeiventris, owing to its size, wide distribution and dense covering of silver or golden pubescence, is one of the handsomest and most conspicuous ants of the American tropics.

Apparently this ant is a popular choice of models for mimics in a number of insect groups. Lenko (1964) reported another cerambycid beetle, Pertyia sericea, as a mimic of C. sericieventris (the similarity of species epithets being no coincidence), and friend and colleague Henry Hespenheide has not only described a zygopine weevil, Copturus paschalis, from Costa Rica as a mimic of this ant (Hespenheide 1984) but also postulated mimicry by Apilocera cleriformis [now Euderces cleriformis] and three other species of Cerambycidae collected by him in central Panama. Henry further noted mimics in the families Cleridae and Mutillidae and the fact that all of the beetle mimics of this arboreally foraging ant are themselves woodborers or predators of woodborers as larvae.

It is interesting that Fisher (1931), in his description of E. velutinus, made no mention of the mimicry, while Wheeler (1931) in his paper about C. sericeiventris discussed this in great detail. He further noted the diversity of cerambycids here in our North American fauna that mimic ants. These include species in the genera Clytoleptus, Euderces, Cyrtophorus, Tilloclytus and—most strikingly—Cyrtinus pygmaeus, our smallest species of Cerambycidae which occurs on dead wood among small ants such as Lasius americanus, and Michthisoma heterodoxum which resembles small Camponotus pennsylvanicus workers. I’ve not yet encountered M. heterodoxum, which seems restricted to the southeastern Coastal Plain, but I have beaten C. pygmaeus from dead branches and can personally attest to the effectiveness of their mimicry—some slight something about the way they moved made me question my immediate assumption that they were ants and caused me to take a closer look at them before I shook them off the beating sheet. I wonder how many times before that I collected this species without realizing it!


Fisher, W. S. 1931. A new ant-like cerambycid beetle from Honduras. Psyche 38:99–101.

Hespenheide, H. A. 1984. New Neotropical species of putative ant-mimicking weevils (Coleoptera: Curculionidae: Zygopinae). The Coleopterists Bulletin 38(4):313–321.

Lenko, K. 1964. Sobre o mimetismo do cerambicideo Pertyia sericea (Perty, 1830) com Camponotus sericeiventris (Guerin, 1830). Papéis Avulsos de Zoologia (São Paulo) 16:89–93.

Wheeler, W. M. 1931. The ant Camponotus (Myrmepomis) sericeiventris Guérin and its mimic. Psyche 38:86–98.

Copyright © Ted C. MacRae 2013

Featured Guest Photo: A Spectacular Case of Mimicry

On occasion I receive photos from readers that are so remarkable I simply must share them (with the owner’s permission, of course). Recently I received a note from Len de Beer in Maputo, Mozambique, who was looking for help identifying a tiger beetle he had photographed on the beaches of the Maputo elephant reserve. My knowledge of Afrotropical tiger beetles is rudimentary, so I had to tap the expertise of fellow cicindelophile Dave Brzoska for the ID (many thanks, Dave), but in the ensuing correspondence Len sent me the following photograph that he took of another tiger beetle species while living in Madagascar:

The mimic: Peridexia hilaris

The mimic: Peridexia hilaris | Anzojorobe, Madagascar (photo © Len de Beer) 

A spectacular species to be sure, but the story behind its appearance is even more remarkable. This tiger beetle is one of two species in the Madagascan-endemic genus Peridexia, both of which exhibit color patterns that are a near-perfect match for that of the local pompilid wasp, Pogonius venustipennis (see photo below). According to Pearson & Vogler (2001), not only do these tiger beetles share the wasp’s bright yellow and black color pattern, but they also run in constant small circles (rather than the distinct, straight-line sprints that are more typical of tiger beetles) and fly readily when frightened, only to land again on the forest floor. These running and flying behaviors more closely resemble the foraging movements of the wasp than the movements of a typical tiger beetle, resulting in mimicry so effective that even tiger beetle collectors have been fooled and stung on the fingers when they attempted to collect their first Peridexia!

The model: Pogonius venustipennis

The model: Pogonius venustipennis (photo © Len de Beer)

Camouflage is the most widely observed predator avoidance mechanism in tiger beetles, with numerous species known whose color patterns closely resemble or otherwise allow them to blend in with the color and texture of the soils found in their preferred habitats. Nevertheless, mimicry is common enough (although anecdotal evidence still far outweighs true experimental evidence). Pearson & Volgler (2001) list examples of tiger beetles resembling mutillid wasps (commonly called “velvet ants”) from North and South America, as well as India, and also mention a South American tiger beetle species, Ctenostoma regium, that is the same size and shape as Paraponera clavata (or “bullet ant”), a large solitary species that is purported to pack the most painful of all insect stings (that this is true, I am inclined to agree). Tiger beetles can also serve as models—there is a katydid in Borneo whose immatures bear a remarkable resemblance to arboreal species of tiger beetles in the genus Tricondyla (Pearson & Vogler 2001, Plates 26 and 27). It has also been suggested that mimicry in tiger beetles might not be restricted to Batesian associations (unprotected mimic and harmful model) but may also include Müllerian associations (both model and mimic are distasteful or harmful).

My sincere thanks to Len de Beer for allowing me to post his photographs of this remarkable tiger beetle and the wasp it mimics.


Pearson, D. L. & A. P. Vogler.  2001. Tiger Beetles: The Evolution, Ecology, and Diversity of the Cicindelids.  Cornell University Press, Ithaca, New York, xiii + 333 pp.

Copyright © Ted C. MacRae 2013 (text)

Desmiphora hirticollis: Crypsis or Mimicry?

During my stay in Corrientes, Argentina last month, I was invited to spend the day with a colleague at his “camp” in Paso de la Patria. Located on the banks of the massive Rio Paraná at its junction with the Rio Paraguay, this small resort community boasts large tracts of relatively intact “Selva Paranaense,” which together with the Atlantic Forest in southeastern Brazil forms the second largest forest ecozone in South America outside of the Amazon. As my colleague skillfully prepared matambre, chorizo, and vacío (typical cuts of meat in Argentina) on the parilla (wood grill) at his camp, I explored the surrounding forest for insects. Early April is late in the season, and with generally droughty conditions in the area for the past several months there were few insects to be found. My luck improved, however, when I came upon a small area with stacks of fresh cut logs from recent wood cutting operations scattered through the area. Wood boring beetles (families Buprestidae and Cerambycidae) are often attracted to such wood piles, so approached each one slowly to look for day-active species of these beetles. After inspecting several piles without seeing anything on them, I began carefully turning over the logs to look for nocturnal species that tend to hide on the undersides during the day. Shortly I came across this highly cryptic species of cerambycid, and further searching revealed a fair number of these beetles hiding within the dozen or so log piles that I examined.

Desmiphora hirticollis on freshly cut guayabi (Patagonia americana) | Corrientes Prov., Argentina

I instantly recognized the genus as Desmiphora, an exclusively New World genus characterized by the presence of fasciculate tufts (or “pencils”) of erect or suberect hairs. Most of its nearly 50 species occur in Brazil, but two species extend as far north as southern Texas (Giesbert 1998). One of these is Desmiphora hirticollis, a widespread species found as far north as Corpus Christi, Texas and as far south as Bolivia and Argentina. I thought these beetles looked an awful lot like that species, and I later confirmed its identity as such due to its piceous (glossy brownish black) integument and the presence of small black pencils just before the elytral apices.

Adults are nearly impossible to see from overhead due to cryptic coloration…

The wood piles contained logs from several tree species, but all of the beetles that I encountered were on logs of guayaibi (Patagonula americana), a member of the family Boraginaceae and a characteristic component of Selva Paranaense (also an important timber species in Argentina). The number of individuals that I found and their occurrence only on guayaibi suggests it serves as a larval host for the beetle. Duffy (1960) described the larva from specimens collected out of Sapium sp. (family Euphorbiaceae), but in Texas this species is collected most often on Cordia spp. and Ehretia anacua (Rice et al. 1985)—both in the family Boraginaceae—with adults having been reared from Cordia eleagnoides (Chemsak & Noguera 1993).

…while the hair tufts may function in obscuring the body outline…

It seems obvious that coloration of the beetle and its pencils of hair function in crypsis. From overhead the beetles are almost impossible to discern as they sit motionless on the similarly colored bark of their host trees. Even in profile or oblique views where the body becomes somewhat more visible, the pencils seem to break up and obscure the outline of the body. I wonder, however, if crypsis is the only function of the pencils—Belt (2004) described the strong resemblance of another species in the genus, D. fasciculata—a similarly penicillate species, to short, thick, hairy caterpillars (insectivorous birds often refuse to prey upon hairy species of caterpillars). That species can be seen sitting openly on foliage during the day, while D. hirticollis seems to be strictly nocturnal; however, cryptic and mimetic functions need not be mutually exclusive, so perhaps for this species the pencils function a little for both.

…or perhaps even mimicking ”hairy” caterpillars.


Belt, T. 2004. The Naturalist in Nicaragua. Project Guttenberg eBook.

Chemsak, J. A. & F. A. Noguera.  1993.  Annotated checklist of the Cerambycidae of the Estacion de Biologia Chamela, Jalisco, Mexico (Coleoptera), with descriptions of new genera and species.  Folia Entomológica Mexicana 89:55–102.

Duffy, E. A. J. 1960. A Monograph of the Immature Stages of Neotropical Timber Beetles (Cerambycidae). British Museum of Natural History, London. 327 p.

Giesbert, E. F. 1998. A review of the genus Desmiphora Audinet-Serville (Coleoptera: Cerambycidae: Lamiinae: Desmiphorini) in North America, Mexico and Central America. Occasional Papers of the Consortium Coleopterorum 2(1): 27–43.

Rice, M. E., R. H. Turnbow, Jr. & F. T. Hovore. 1985. Biological and distributional observations on Cerambycidae from the southwestern United States (Coleoptera). The Coleopterists Bulletin 39(1):18–24.

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.


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