This blog is one year old today, and after taking a look at my first post, I thought I might take the opportunity to point out that you don’t have to go to Singapore or Australia to see fancy square-mesh cocoons. Of course, if you’re already in one of those places, then you’re all set.
Last July my friend Carrie and I were walking along a forest-field edge in Northampton, Massachusetts, when Carrie spotted this little cocoon (about 7 mm long) hanging from the underside of a goldenrod leaf:
The wheels turned in my head for a few moments while I considered the various lacy cocoons described on pages 220-222 of my book (all of which, I’ll concede, are made of silk rather than of caterpillar hairs as in Cyana meyricki). When I looked above me and saw that we were standing under an aspen tree, my mind leapt to Wockia asperipunctella (Urodidae), which, as I wrote in the first paragraph of the “lacy cocoons” section, makes a coarse, rectangular-mesh cocoon on aspen and willow, and was only recently discovered in Ontario.
I wondered if finding this species in Massachusetts might be a significant discovery, based on what little I knew about it, and an internet search turned up a reference to a paper* by Jean-François Landry, which promised to have some more information about its range. Not having access to the paper, I asked Dr. Landry about it and sent him this photo. He agreed that the cocoon probably belonged to Wockia asperipunctella and sent me the paper, which shows that the species is now known to occur across Canada, and in the northeastern US from Michigan to Pennsylvania and southern New England (there is a single dot here, which might be in Connecticut, Rhode Island, or Massachusetts). Dr. Landry examined specimens in collections going back at least to the 1940s, and based on the collection locations, including remote wilderness areas, he is convinced that this species is native to both Europe and North America, rather than being a recently introduced European species as had previously been suggested. He says it was probably overlooked for so long because the adult, in addition to being nondescript, is diurnal, so it is usually missed by surveys that rely on attracting moths to lights at night.
Five days after I collected the cocoon, the moth emerged…
…or tried to. This was as far as it got. Normally, when I’m reasonably sure of an insect’s identification, I let it go on with its life after photographing it, but this one had its forewings stuck inside its pupal case and so was doomed. Plus, all four of the spread specimens shown in Dr. Landry’s paper have very plain hind wings, not boldly patterned ones like these, so it wasn’t clear that this was really the same species. So I sent him the specimen and he examined its genitalia, confirming that it was indeed Wockia asperipunctella.
Seabrooke Leckie, coauthor of the new Peterson Field Guide to Moths of Northeastern North America (which will be available the week after next), included a photo of a happier adult Wockia asperipunctella at the bottom of this post, in which she reports having given this species the common name “Shaggy-spotted Wockia,” though she really wanted to call it a Wookiee. In this she showed more restraint than David Adamski, who recently described Wockia chewbacca from western Mexico.**
* Landry, Jean-François. 1998. Additional Nearctic records of Wockia asperipunctella, with notes on its distribution and structural variation (Lepidoptera: Urodidae). Holarctic Lepidoptera 5(1):9-13.
** Adamski, David, Karina Boege, Karina; Jean-François Landry, and Jae-Cheon Sohn. 2009. Two new species of Wockia Heinemann (Lepidoptera: Urodidae) from coastal dry-forests in western Mexico. Proceedings of the Entomological Society of Washington 111(1):166-182.