A few days after returning from travel through northern Argentina, I found a jar on my desk with this beetle in it. One of my colleagues has seen it in the field while I was away and figured I would be interested in seeing it. Although I’m half-a-world away from home, I immediately thought of our North American species Chelymorpha cassidea when I saw it. Armed with this hunch, I typed “Chelymorpha Argentina” into Google, and the first result that came up was a paper by Hamity & Neder de Román (2008) about the species Chelymorpha varians in Argentina and its potential as a biocontrol agent for the widespread weed Convolvulus arvensis. Included in the paper was a plate showing variability of coloration and maculation in the adults, and my individual was a dead ringer for the species. Still, getting a species ID on the very first hit of the very first search attempt just seemed too easy, so I consulted the wonderfully comprehensive Cassidinae of the world – an interactive manual. This site, too, contained multiple images of Chelymorpha varians showing an extraordinary range of variability in color (from yellow to red) and degree of maculation (from immaculate to heavily maculated). A quick perusal of other species indicated as similar or also occurring in Argentina turned up nothing nearly as similar and convinced me that I had, indeed, arrived at a correct ID.
As indicated in the above cited paper, and like our own C. cassidea, species in the genus Chelymorpha are associated almost exclusively with plants in the genus Convolvulus. I would have preferred to photograph the beetle on foliage of this plant, but not knowing precisely where I might find it I decided to do white box instead. I got some printer paper and was looking for a cardboard box to line the inside with it when I spotted a styrofoam cooler of just the right size.
These are okay white box photos, but I’ve decided if I want to do white box right I need to get a larger flash unit that is a little easier to work with off the camera. Right now I have only the small twin-flash heads from my MT-24EX—their small size makes them difficult to manipulate off the camera, and leaving them attached to their bracket limits the directions in which they can be oriented relative to the subject. As a result, I had to use more heavy-handed post-processing in these photos than I normally like to do in order to get the levels right. Hmm, I have a birthday coming up in about a month…
REFERENCE:
Hamity, V. C. & L. E. Neder de Román. 2008. Aspectos bioecológicos de Chelymorpha varians Blanchard (Coleoptera: Chrysomelidae, Cassidinae) defoliador de convolvuláceas. Idesia 26(2):69–73.
Copyright © Ted C. MacRae 2012
Nice beetle and nice demonstration of the wonders of styrofoam. When I went to look for a styrofoam cup to try Myrmecos’ lighting technique a few weeks ago I had a hard time. The stacks of styrofoam cups in the cafeteria had all mutated into cardboard! I finally begged one from the back corner of a student’s desk, but that seems to be the last one around. I’m wondering if I should stock up on the ones in grocery store while they are still extant (like stocking up on 40 watt incandescent bulbs for Berlese Funnels before they are all gone).
Can’t say that tortoise beetles are very common here either. I don’t think I’ve seen one and according to LeSage’s checklist no Chelymorpha make it into Alberta. However, there is an almost as nice Jonthonota nigripes and a golden Deloyala guttata that both like morning glories. Seems like a good excuse to plant some this spring
Those are both pretty little species – not quite as large as Chelymorpha but certainly no less attractive (Deloyla perhaps more so with its golden iridescence).
Very interesting!
🙂