I won’t call this a taxonomy fail, since Patrick is clearly not a taxonomist, or even the first person to confuse a beetle with a cockroach. Nevertheless, I was amused at Patrick’s amazement with the “colorfull cockroach” that he found and his palpable excitement that it might be a new discovery.
Well, I was amazed about this type of cockroach so, I would like to know if it is a cockroach or what because I know you guys will be also interested about checking out this type of bug.
Thanks please answer fast 🙂
Maybe is a new kind of cockroach not discovered yet.
Fortunately, the folks at What’s That Bug were able to correctly identify this as Euchroma gigantea (giant metallic ceiba borer), a beetle in the family Buprestidae (and the largest such species in the Western Hemisphere). An interesting note about this photo is that it shows the beetle with some – but not all – of the green pulverulence (dusty coating) that these beetles exhibit over the elytra upon emergence from their host tree. This coating is quickly worn off as the beetle goes about its activities, and most museum specimens of the species lack it completely – giving the beetle a purplish appearance as seen on the left elytron of the beetle in this photo. Even handling a freshly-emerged specimen to mount it on an insect pin would likely result in loss of much of the coating, so it is quite difficult to preserve specimens in their lime-green dusty state.
Copyright © Ted C. MacRae 2010
Beetles In The Bush 
Lets just cut the crap here for a moment and say what all entomologists really think about buprestids: they look like colorful cockroaches…
😀
Right on, Roberto!
At least there are other beetles that don’t look like cucarachas! And it is at least true that one can tell these apart by antenna length.
Does resemble a cockroach, from this angle at least 😀
Yeah, well I would imagine Malaysia has some rather colorful cockroaches 🙂
What is the function of the wax? Cuticular wax blooms are often associated with desert insects as a way to enhance moisture retention. Moisture retention would not seem to be a challenge for this beetle.
Does the wax harbor fungus that is transmitted to new sites? Does it make the beetle better able to slide out of its pupal chamber? Is it distasteful, a deterrent to predators? Is it a way to “mark” mated females?
I don’t know what role it serves with this beetle. You are right that many desert beetles have such waxy blooms, which includes a large number of Buprestidae. Whether the bloom in this species also serves that function or is a holdover from taxonomic relatedness remains to be seen. I have my doubts about a role in water retention because it is so easily rubbed off after emergence – doesn’t make much sense. Any of the other suggestions you make have merit, but which (if any) are true is a mystery.
Thanks for the good site! I photographed and handled a newly emerged specimen in Costa Rica a few weeks ago and the powder was quite aromatic. I suspect a defensive function, but that is conjecture and what I’m looking on the web for confirmation of.
I’ve not heard of them being aromatic before, but if so that does imply a defensive function. Nevertheless, the powdery bloom rubs off very easily (I’ve never seen a preserved specimen with it), so most people seem to think it has some function in helping the adult to emerge. See discussion under my post North America’s largest jewel beetle.
The bloom does make them slick, and it probably would be a good lubricant to help them get out of the wood. The fact that the bloom is common in wood-boring beetles also suggests this is why it originally evolved. It also makes them very conspicuous, so a protective function built into the bloom would also be adaptive. Good MS problem for someone!
Good points, David – although if it were strictly related to assisting emergence you would expect it to be universal thoughout the family. In fact it seems to be much more common in certain taxa (Chalcophorinae) and especially species in dry/desert habitats. For that reason I think it at least partially has something to do with thermoregulation and/or water conservation. I can’t think of any species here in the eastern U.S., even in the Chalcophorinae, that exhibit bloom to any degree. Nevertheless, that doesn’t mean it isn’t related to assiting emergence – either originally or as a pre-adaptation. Yes, a very good thesis/dissertation project!