Males of A. lordi are easily recognized by the orange-brown color of the last 2-3 sterna, in sharp contrast to the mostly strongly metallic integument of the rest of the ventral surface (females and both sexes of all other species have all sterna concolorous). The metallic reflections on the head, pronotal sides, and elytral apices – along with size – further distinguish A. lordi from other African species.
As is typical with so many tropical insects, little is known about the biology and lifestyle of species of Agelia. The bold, contrasting coloration of especially the African species would seem to make them conspicuous to predation, but this seems to be the result of a mimetic association with noxious species of blister beetles (family Meloidae) in the genus Mylabris. I saw one of these (see Mylabris oculatus in South Africa) in association with A. petalii during my 1999 visit to South Africa, and the resemblance was so strong that I had do a double-take every time I saw one to determine whether it was Agelia or Mylabris.
REFERENCE:
Gussmann, S. M. V. 2002. Revision of the genus Agelia Laporte and Gory (Coleoptera: Buprestidae). Annals of the Transvaal Museum 39:23–55.
Copyright © Ted C. MacRae 2011
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What a beautiful beetle (and a great photo)!
Thanks, Anne.
Interesting! I have to look into this type of mounting. Often I just hate to pin the specimens. probably not appreciated by research collection curators
Europeans and Japanese almost always mount on cards, considering it almost sacriligeous to ‘damage’ the body with a pin. I find the practice overly cumbersome and detest the manner in which it completely obscures the ventral surface (often so important in taxonomy). Of course, I am a product of the American tradition of mounting directly on pins (which the Europeans equally detest on aesthetic grounds). Either way, they’re still just dead bugs lined up in a drawer!
Here’s something I’ve been wondering about: is there a standardized method for determining whether a particular insect is toxic or has a noxious taste? For example, in this case, how would we going about finding out whether it is a perfectly edible beetle mimicking a more noxious species, or is foul-tasting in its own right?
I can’t really think of a more direct way than just tasting it oneself (or persuading a soon-to-be-former friend to do it), but this seems – risky. And mashing it up to run through an HPLC looking for possible defensive chemicals seems kind of excessive.
It’s a good question, and an important one since it determines whether the mimicry association is of the Batesian or Mullerian type. I’m not familiar enough with prey palatability studies to say for sure how they are done, but presumably captive birds and lizards are used as the test subjects rather than the experimenter himself 🙂 Ecological theory also predicts that the model will be much more common than the mimic (and Mylabris are much more commonly encountered than Agelia), and I’m sure taxonomic affinity can be highly predictive (i.e., no noxious species of Buprestidae are known, at least that I am aware of, while documentation of noxiousness across nearly all Meloidae is abundant).