The ultimate jaws on a longhorned beetle!

Some 23 years ago, I departed on my first ex-U.S. insect collecting trip. I was still a youngster—barely into my 30s—but had by then a well developed interest in woodboring beetles of the families Buprestidae and Cerambycidae. I had spent the previous eight years since graduate school collecting these beetles throughout Missouri, work that led to the publication of my faunal treatments of the two families for the state (MacRae 1991, 1994), and even begun collecting insects outside of Missouri in other states such as Texas, Arizona and Florida. Although I was still cutting my teeth as a collector, I yearned for the tropical experience, and in December 1989 to January 1990 I got the chance to spend three weeks in one of the most tropical localities I could imagine—Ecuador! I’ve collected in many countries since then, but that first tropical collecting trip remains one of my most cherished experiences.

Criodion rhinoceros Bates 1870 | Sucumbios Province, Ecuador (New Country Record)

Of course, being as young and green as I was, I didn’t really know what any of the insects I was collecting were beyond family level (if that!), and the numbers were so overwhelming compared to anything I had experienced previously that all I could do was collect as much as I could using the techniques I had figured out to that point, process them all when I got back, and then hold them for the future when I would either study them myself or make them available to other specialists. In the years since, Buprestidae have become the primary focus of my studies, relegating any non-Nearctic Cerambycidae in my collection to the sidelines. Since I don’t now and probably will never do serious work on Neotropical Cerambycidae, I’ve begun sending them to specialists who do work on them for identification or to be utilized as desired in their research. Much of the Cerambycidae were sent to Frank Hovore, an expert of Ecuadorian Cerambycidae who kindly identified them for me before tragically passing away while on a collecting trip to that very country. Some of the larger specimens were not sent, however, because I had used them to create an “Oh wow!” drawer (see photo on My Collection page). After Frank’s passing, I decided to try identifying the longhorned beetles in that drawer, most of which I was able to identify using Larry Bezark’s incredible website, A Photographic Catalogue of the Cerambycidae of the [New] World. There was one, however, that I was not able identify, despite the fact that it seemed to be the most easily identifiable of all due to remarkable horn-like processes arising from the top of the mandibles. I scanned repeatedly through the photos of species in all genera that looked even remotely similar. Criodion seemed most likely, but none of the species photographed sported such unique mandibular armature.

Males sport remarkable horn-like processes arising from the mandibles.

Stumped, I emailed the top photo to Brazilian coleopterist and cerambycid specialist Antonio Santos-Silva (Universidade de São Paulo) and asked for his opinion. He replied that it seemed to be a species of Criodion, noting that the only species of Criodion with this kind of mandible is C. rhinoceros—known only from the Brazilian state of Pará, and a species completely lacking in their collection. I sent him the other photos in this post to give him a better view of the mandibles, and Antonio replied back that both he and colleague Ubirajara Martins agree with the initial ID. My failure to match the specimen with this species in the photographic catalogue was understandable, as this was one of the few species for which no photographs were available. That situation has since been corrected, and the site now features photographs of both male and female specimens—the latter exhibiting quite chunky but not nearly as grossly developed mandibles as the former.

Another view of the male's remarkable mandibular armature

A lateral view of the head resembles that of a rhinoceros!

Bates’ (1870) original description, based only on the male, notes that the spines arise from the upper edge of the mandibles near the middle and incline towards each other, crossing at the apices and giving the head of the beetle, viewed in profile, the curious resemblance to that of a rhinoceros. Certainly no other species in the genus bears such extraordinary modifications of the mandibles, and if there are others in the family, I am not aware of them and they must be very few in number. One can only speculate on the function of such a modification, but since they are present only on the males a sexual or mating-related function could be considered likely. If any reader has information or thoughts about extreme mandibular modifications such as this and their possible functional significance please let me know.

Males sport remarkable horn-like processes arising from the base of the mandibles

And of course, the BitB face shot!

The collection of this species in Ecuador adds another species to that countrys’ already rich cerambycid fauna (Antonio confirmed that it is a new record for Ecuador). I’ve picked up a smattering of other Cerambycidae from South America over the past ten years, so I’m going to send them all to Antonio for ID and allow him to keep whatever is interesting for his research or the University’s collection. I will include this remarkable species in the package as a gift—considering its status as the only known voucher for the species in Ecuador, I think his institution’s collection will be a more appropriate repository for it than my “Oh wow!” drawer.


Bates, H. W. 1870. Contributions to an insect fauna of the Amazon Valley (Coleoptera, Cerambycidae). Transactions of the Entomological Society of London 1870:243–335, 391–444.

MacRae, T. C. 1991. The Buprestidae (Coleoptera) of Missouri.  Insecta Mundi 5(2):101–126.

MacRae, T. C. 1994. Annotated checklist of the longhorned beetles (Coleoptera: Cerambycidae and Disteniidae) known to occur in Missouri. Insecta Mundi 7(4) (1993):223–252.

Copyright © Ted C. MacRae 2013

Vinerunt, futuerunt, ierunt

Very rough translation: They loved us, then left us. (the cicadas, that is.)¹ 

¹ Guest blogger’s subtext — Maybe if I dazzle the readers with a title in the colorful language of Pompeiian graffiti, they’ll forgive me for not posting pictures as beautiful as Ted’s. Well, anyway…

On this year’s US Independence Day, we in the St. Louis area were able to proclaim our freedom from the 5-week-long din of cicadas, or so the TV “news” reporters would have us believe. For me, it was more of a return to the dominance of human-made noise; the faint drone of a distant highway, the monotone roar of a neighbor’s lawn mower, the repetitively plosive engine of one of the many diesel pickups that float by, with the CD player’s bass thumping at an almost certainly hearing-damaging decibel level.

Magicicada burrows

I started my celebration early in the day, by doing some gardening and rearranging in the yard. Moving a pile of concrete paving stones, I reached the bottom one and lifted it, and was greeted with a view of abandoned nymphal emergence burrows made by just a few of the many thousands of periodical cicadas that graced my yard with their presence this year. The burrows were already showing wear at the edges in their disuse. A little later later in the morning, I heard the whoooooooa-ooh of a last, lone Magicicada tredecim male from the hackberry tree—first one call, then another, then no more. But nature’s course proceeds, and as afternoon drifted into evening, I was pleased to hear the first of the dogday, or annual, cicadas of the genus Tibicen. These are not truly annual; They emerge every year, but actually take several years—4 or 5, it is said—to develop from egg to adult. 

The four Magicicada species that can be found in the St. Louis area, near the western edge of Periodical Cicada Brood XIX (a.k.a. the Great Southern Brood), are famous for their intermittent emergence as adults, every 13 years. (Life spans of 17 years occur in three, more northern species that do not occur in the St. Louis area). In fact, during years to either side of the two emergences of Brood XIX that I’ve experienced since moving to this area 24 years ago, I have always heard, and if really lucky, seen a few, one or two years before and after the “scheduled” emergence. But, the vast majority stick to the plan of feeding on the xylem sap of tree roots as subterranean, tan-colored nymphs for 13 seasons before coming out of the ground, then molting to the ever-so-buggy-looking, winged, black insects with red eyes and wing veins, that “freak everyone out” during their mass emergences. 

The mass emergence is all about reproduction, the successful transmission of genes to the next generation—you know, Darwinian fitness. When a female happens to “like” the song of a particular male, she flies to him, then is courted a for a bit with a different song, before “succumbing to his charms”. Mating typically takes place up in trees. But, being amoral creatures of little brain or scruples, they may choose indelicately to copulate on a porch rail or other such public place. 

Magicicada mating

Magicicada sipping Gentiana andrewsii

Consumed with sex, the adults don’t eat much, but occasionally one sees a cicada poking its proboscis into some soft plant tissue for a drink of sap (clearly exhibiting the relationship of these large insects to those smaller sap-feeders, the aphids and such). A little sap-drinking does little damage to plants, but the insertion of eggs by the mated females into small twigs of woody plants can do quite a bit of “natural pruning”. This would be more of a concern if it happened every year, I suppose, but it really also does little damage in the long run, especially on a mature tree. Still, I would have appreciated it they hadn’t found my recently planted black gum tree such an attractive oviposition site. 

Magicicada damage on Acer saccharum

Magicicada meets Nyssa sapling

But I don’t begrudge them this. I miss their mass serenade. I treasure the remembered sight of a corpulent hairy woodpecker muddying itself to pull one nymph after another from rain saturated ground. I delighted in seeing a surprisingly chubby chipmunk perched fearlessly on an exposed root as it munched a cicada whose wings never properly expanded. Perhaps best of all was watching a red-shouldered hawk clumsily hop about on the lawn to snarf up cicadas that weakly fluttered to the ground. But now, the periodical cicadas are, till May of 2024, mere shells of their former selves. 

To end on a pretty note, here’s a gaudy cicada that was attracted to lights of the scientific station’s laboratory building in Yasuní National Park, Ecuador, and obligingly posed for a photo on the windowsill.

Ecuadorian cicada

Copyright © James Trager 2011

Trilogy of Terror

Last week, Alex at myrmecos tagged me with a fun new meme called These are a few of my favorite stings…. It’s simple – list the things which have stung you (biting doesn’t count), and tag three others for their tales of envenomization. Of course, being the dedicated myrmecologist that he is, Alex leads off with a most impressive list of venomous arthropods, and he selected worthy competition in buzzybeegirl and bugeric.  But me?  I have, for the most part, succeeded in avoiding stings by focusing on a group of insects (beetles) that never evolved such structures.  My domestic list is short and mundane – honey bees, paper wasps, sweat bees, fire ants – and even those not very often.  Alex, however, suspected I might have some tales from exotic lands – thus, I offer the following trilogy and tag Art, Doug, and Kolby.

Tale 1
When I made my first Neotropical collecting excursion some 20 years ago to Ecuador, I was warned by my guide about large, black ants that he called “Congas.” I later learned the species to be what many people call the bullet ant (Paraponera clavata). Now, I’m not an expert on which arthropod truly has the most painful sting, but many people knowledgeable about such matters say it is this species – and I believe them! We were camped out in Sucumbios Province east of Nueva Loja (also called “Lago Agrio”) at an Amazon forest site where recent construction had left rows of month-old slash lining both sides of a 2-km stretch of new road through the forest – can you say woodboring beetles? I roamed up and down that stretch of road, picking a wonderful diversity of longhorned beetles (Cerambycidae) and jewel beetles (Buprestidae) off the slash. At one point, I encountered a whole tree crown laying by the side of the road that required some clambering to get at the beetles crawling on its inner branches. At one point, I braced myself with my arm against a branch and immediately felt an excruciating pain. I looked at my arm and saw one of these large ants clamped onto my arm and quickly slapped it off. I really don’t think words can describe how painful that sting was, and not only did it throb for the rest of the day, but I actually felt sick for the next several days (though I still managed to keep roaming the slash rows). I don’t know if the bullet ant I captured right afterwards was the one that stung me, but I still took great delight in impaling a #2 insect pin through its thorax after I returned home.

Tale 2
Alex mentioned one plant – stinging nettle (Urtica dioica, which also lines one of my favorite mountain bike trails), but I’ve also had a run-in with a much more formidable plant in Mexico. Mala mujer (Cnidoscolus angustidens), which translates as “bad woman” in Spanish, deserves all the respect you can give it. Reported to be one of the most painful stinging nettle-type plants known, it grows commonly from the arid southwest down into the dry, tropical thorn forests of southern Mexico where my colleague Chuck Bellamy and I have made several trips in recent years to search for jewel beetles. One quickly learns to recognize this distinctive euphorbiaceous plant by its green palmate leaves with white veins and thick covering of yellow, stinging trichomes. Unfortunately, in my zeal for beating buprestids from Leucaena diversifolia (netting several of the rare Pelycothorax tylauchenioides and a now paratypical series of what was then an undescribed species of Agrilus), I forgot to maintain my lookout for this common understory plant and got a swipe across the knuckles. Not only did the extreme pain last for hours, but my ring finger began swelling so worrysomely that we stopped in a hospital looking for somebody to cut the ring off. My poor Spanish brought me no sympathy (or service), but fortunately the swelling began subsiding that evening and I didn’t lose my finger. I did, however, live with a rash for the next several days that developed into a hard, purple skin discoloration for the next several weeks.  Bad woman, indeed!

Tale 3
I debated whether to include this experience, but the terror was real so here it is. I wrote about it recently in an article called “Dungers and Chafers – a Trip to South Africa” that appeared in the December 2008 issue of SCARABS Newsletter. Enjoy this excerpt:

After arriving at the park [Borakalalo National Park, North West Province], I could hardly contain myself – I was so anxious to start collecting… We drove through the park for a little bit looking for a good spot to pull over and begin the hunt. After finding such a spot, I grabbed my trusty beating sheet and began doing what I have done so many times before – walking up to a tree, giving a branch a whack with the handle of my net, and hoping to see some prized buprestid laying on the beating sheet. The habitat was ideal for this – dominated by low, spreading acacias such as Acacia tortilis and A. karoo. Buprestids love acacias! I had already learned this in my travels through the American desert southwest and down into Mexico and South America – surely it was the same in South Africa. The first whack yielded nothing – typical. Even when collecting is good, buprestids are never “dripping from the trees,” and often one must literally beat dozens and dozens of trees to really get a good idea of the diversity and abundance of buprestid species that are active in a given area. I whacked a few more trees, with similar results. I then spotted one particularly large acacia tree – something about it said, “beat me!” I walked over to it and gave a branch a whack. All at once, it seemed as though the world was exploding! The air was suddenly abuzz with dozens of large, flying insects, whirring and swirling all around me. My first thought in that initial moment of terror was that I had whacked a hornet’s nest – who knew what kinds of deadly, venomous wasps one might encounter in Africa? Instinctively I ducked and started running, but within a few moments I realized that I was not being chased. Cautiously, I sneaked back towards the tree (after stuffing my heart back down my throat) and realized that they were not hornets after all, but instead beetles. I looked more closely and saw that the tree was literally alive with dozens and dozens of large, green cetoniines resembling our own green June beetle, Cotinis nitida (L.), which seemed to be attracted to the small, white blooms that covered the tree in profusion. I netted a few of the beetles, which I would later determine to represent the common savannah species Dischista cincta (de Geer) (Photo 2). Such was my welcome to Africa, where it seemed the trees literally are ‘dripping’ with beetles!

Disticha cincta (de Geer)

Photo 2. Disticha cincta (de Geer)

Copyright © Ted C. MacRae 2009

Add to FacebookAdd to NewsvineAdd to DiggAdd to Del.icio.usAdd to StumbleuponAdd to RedditAdd to BlinklistAdd to Ma.gnoliaAdd to TechnoratiAdd to Furl