Identification, Images, & Information
For Insects, Spiders & Their Kin
For the United States & Canada
Clickable Guide
Moths Butterflies Flies Caterpillars Flies Dragonflies Flies Mantids Cockroaches Bees and Wasps Walkingsticks Earwigs Ants Termites Hoppers and Kin Hoppers and Kin Beetles True Bugs Fleas Grasshoppers and Kin Ticks Spiders Scorpions Centipedes Millipedes


TaxonomyBrowseInfoImagesLinksBooksData
Photo#8730
white-striped leaf beetle - Calligrapha bidenticola

white-striped leaf beetle - Calligrapha bidenticola
near Ailsa Craig, Ontario, Canada
May 26, 2004
Length about 5-6 mm; in damp meadow on stem of Bristly Buttercup (Ranunculus pensylvanicus). My guess is some kind of Chrysomelid but not sure - anyone know the species or genus?

Images of this individual: tag all
C. californica? x2 mag. - Calligrapha bidenticola white-striped leaf beetle - Calligrapha bidenticola

likely Calligrapha bidenticola --det. S.M. Clark
Moved from Ragweed Leaf Beetle.

most of the images placed until now on the Zygogramma suturalis page show in fact C. bidenticola

Moved
Both images moved from Zygogramma to Z. suturalis.

can be moved to Z. suturalis page
*

Possibilities: Zygogramma , Calligrapha,
Resembles Zygogramma suturalis (Dillon (1), plate LXVIII #8), or maybe one of the Calligrapha, such as C. californica (Dillon (1), plate LXVIII #12). Dillon keys the two genera based on tarsal structure--not easy to see in a photograph, most likely. However, if you look at a higher mag. view of the photo at right, you might see it. Zygogramma: tarsal claws parallel, united at base. Calligrapha: tarsal claws divergent. Hmm. In the photo at right I just see one claw on the tarsi (last segment of legs). Again, a higher mag. view of that region might help.

Of course, there are a lot of leaf beetles out there. I'm just looking at the pattern, basically.

Patrick Coin
Durham, North Carolina

 
Calligrapha
Thanks for the tips, Patrick. The original (2x) shot seems to show two tarsal claws at almost 180 degrees from each other (divergent), favoring Calligrapha. The stripes shown in the C. californica photos here and here look similar but are missing the "fireman's ax" pattern near the pronotum in my photo. Maybe there's considerable variation in the shape of the stripes in this species, or maybe there are other species that lack the typical Calligrapha spotting among the 24 additional Ontario species in that genus, and it's one of them (?)

 
Yup, some images
I'd like to see the claws on Calligrapha for comparison--remember, I've no experience on these things, I just have a reference book!

Note this image of Zygogramma from Oklahoma, by Charles Lewallen. He's active on BugGuide, maybe he can comment on the identification. The pattern does look close to your beetle--a bit of the "fireman's ax".

Lots of images of Calligrapha out there--I don't see any that look so close, but as you say, there are several species. That C. californica shown by Dillon does have a bit of the "fireman's ax" pattern on the elytra.


Patrick Coin
Durham, North Carolina

 
Calligrapha maybe
I'll post the 2x mag. image soon. It's pretty fuzzy but I think two tarsal claws are visible on the foreleg - a longer one pointing right and a very short one pointing left (or maybe I'm just seeing things?). A second claw isn't visible on the mid and hind legs, maybe due to the angle of view?
I had previously noticed the "half an ax" pattern on the Zygogramma photo by Charles but dismissed that individual because it shows an extra (3rd) white stripe on each elytron. Still, I haven't seen the Dillon image and am not sure how variable these guys can be, so have to keep all possibilities open to account for that.

 
tarsal claws
I conducted small-scale collection of Chrysomelidae from Ambrosia artemisiifolia, as part of my research project. As of current, it has yielded nearly 40 individuals matching the picture, with EXTREMELY little variation in the shape or number of stripes.

Patrick, you mentioned that the tarsal structure can be used to key Zygogramma or Calligrapha. According to Peterson's guide on beetles, the former has tarsal claws nearly touching at the base, and the latter has claws separated. I'm no expert of insects, but the tarsal claws for my specimens are nearly parallel, and only a small separation between the claws. This seems to suggest a species of Zygogramma. I'll try and get a few pictures later.

Comments?

 
specimens
Does the U. of Toronto have an insect collection you can check? In your research project, what name are you using to refer to your collected specimens?

 
specimens
I'm sure U of T has an insect collection somewhere. But as I've mentioned before, my background is not in entomology, so I never bothered to check where it is. I'm just calling it Zygogramma sp. At least for my project, it is not important to key it out to the species.

Also, refer to http://bugguide.net/node/view/14282

They belong to the same species. I collected a mating pair during night sampling earlier today.

 
Calligrapha lunata
I just thought I'd add that this image is identical to the one in Insects, Their Natural History and Diversity of C. lunata.

My reference shows saturalis as dark and says it's "boldly striped". It also shows the notch on the top of the black stripe near the "shoulder". According to this reference I think we have some calligrapha in the zygogramma section. The Calligrapha lunata is a more red-brown stripe and doesn't have that notch in the stripe near the "shoulder". Lunata also does have a "notch" about half way back on the lower brown section. zygogramma's is rounded but smooth.

Here are the images that match the ones in this book.


Z. suturalis


C lunata

However, I don't know the variability in markings for each species. As you can see in my image, it has both the shoulder and the side notches, plus the dark coloring. So perhaps the shoulder notch is a good field mark and the side notch isn't?


Comment viewing options
Select your preferred way to display the comments and click 'Save settings' to activate your changes.