Acanthocinus nodosus on trunk of Pinus echinata | vic. Calico Rock, Arkansas
In my previous post (Oedipodine Rex), I used the term ‘conspicuous crypsis’ to describe the sumptuously beautiful lichen grasshopper, Trimerotropis saxatilis, as an example of an insect that, despite strikingly conspicuous colors/patterns, blends in perfectly with its native surroundings. I don’t think this is a formally recognized ecological concept (and a quick search of the web and my limited ecology literature didn’t turn up anything about it) with any real biological/ecological relevance, but rather just a little irony that personally I find interesting.
The same individual in the above photograph in its original resting spot.
The photographs in this post were also taken during one of my June trips to the sandstone glade complex around Calico Rock, Arkansas and show another insect that I would describe as conspicuously cryptic. This is Acanthocinus nodosus, in my opinion one of eastern North America’s most attractive longhorned beetles (family Cerambycidae). This species occurs across the eastern U.S. (just sneaking up into southern Missouri), where the larvae mine the phloem beneath the bark of dead and dying pines (Linsley and Chemsak 1995). BugGuide describes it as “subtle, yet beautiful” with an antennal span in males reaching a spectacular 120 mm (that’s 5 inches, folks!). Perhaps others have encountered this beetle more commonly further south, but I have previously seen only single individuals on just three occasions—twice in the Ozark Highlands of southern Missouri (one at lights and another searching the trunk of a standing, decadent pine tree at night) and another at lights in Alabama. As a result, I was quite excited to find this individual clinging during the day to the trunk of a large shortleaf pine (Pinus echinata). The tree appeared healthy, but I found adults of several other wood boring beetles crawling on its trunk as well, suggesting that maybe the tree was stressed or in the initial stages of decline.
Subtle, yet beautiful!
I must confess that the first photograph above was staged—I had moved the beetle from its original resting spot and placed it on a part of the trunk where the bark color contrasted more strongly with the beetle to increase its visibility. The second and third photos above and left show the beetle in its original resting spot and illustrate just how cryptic the beetle is when resting on older, more weathered pine bark. Admittedly, the somber coloration of this species is not as extraordinary as the lichen-green of the lichen grasshopper, but I nevertheless find the slate gray with velvet black markings quite beautiful. When mounted on pins and lined up neatly in a cabinet, individuals of this species are as attractive as any dead insect can be. It was not until I saw this individual in Arkansas—and tried to photograph it during the day—that the cryptic function of its coloration and patterning became truly apparent to me. Most species in the tribe Acanthocini (to which this species belongs) also exhibit somber coloration with variable black markings or mottling, although only a handful can be considered as ‘conspicuously cryptic’ as this one.
REFERENCE:
Linsley, E. G. and J. A. Chemsak. 1995. The Cerambycidae of North America. Part VII, No. 2: Taxonomy and classification of the subfamily Lamiinae, tribes Acanthocinini through Hemilophini. University of California Publications in Entomology 114:1–292.
Copyright © Ted C. MacRae 2011
Beetles In The Bush 
NIce photos and blog Ted!
Thank you, Art!
I’m having trouble wrapping my mind around “conspicuous crypsis” Ted, but you certainly have brought us two outstanding examples of beautiful crypsis. The conspicuousness seems to me to be limited to a scale and context at which it is not ecologically relevant, the latter namely, the appearance of the insects in their “normal” place of rest, to a passing predator.
I caught a cerambycid the other day that was both cryptic (though not so at the porch light) and smelly. Are these beetles so tasty and nutritious as to merit multiple lines of defense?
‘Beautiful crypsis’ would have worked equally well as a term but lacks the oxymoronic humor that I desired. We agree that neither term has any ecological relevance and is simply an artifact of context.
I think in the bug-eat-bug world, there’s no such thing as too much defense!
Thanks for letting us know it’s “staged”, but it’s nothing compared to the much-abused Gaussian blurs & other Photoshop misuses by new photographers…or Disney documentary makers forcing lemurs off the ledge. Your “untouched-up” photos are nature at their most natural, slightly relocated or not 🙂
Thanks, Bradley – just trying to keep things on the up and up 🙂
Excuse my ignorance (I take photos if insects but don’t know much about them), but what’s the difference between crypsis and camouflage (like on a leopard or some birds for example)?
Hi Sarah – that’s actually a very good question, and I had to do a little digging to be certain of the answer myself. Apparently ‘crypsis’ is one form of ‘camouflage’ – Martin Stevens in Animal Camouflage uses the latter term to describe all forms of concealment, including not only ‘crypsis’ (strategies to prevent detection), but also ‘masquerade’ (strategies to prevent recognition).
A wolf colored like the surrounding vegetation would be an example of crypsis, while a wolf in sheep’s clothing would be an example of masquerade. 🙂
So on your last post about the nymph you said movement made it visible, is this the same with this amazingly beautiful specimen?
Hi zachynyoga. Actually, I did manage to see this individual without it moving. I had already found other wood boring beetles on the tree, so I was scanning the trunk to look for others. After so many years of scanning tree trunks, I’ve gotten pretty good at picking out certain shapes and color patterns. Think of me as a very experienced predator! 🙂
p.s. The “yogamats.html” tag at the end of your html address will get your comments flagged as spam. Just use the home address and you’ll be fine.
Hi Mr. MacRae,
Amazing, I have probably walked by hundreds of trees with all sorts of creatures hiding on the bark, I will investigate more in depth next time I am out and about.
Thanks for the info.
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This is a gorgeous beetle…interesting that it would be stunning and striking in a collection box, but dull and unremarkable on weathered bark…
Yes, indeed – I wonder how much of my low number of encounters with this species is due to simply walking right by them as they sat on the tree trunk next to me.
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