There are some funky-looking moths out there. One such species is the Light Marathyssa. In the early days of mothing, just like in the early days of birding, observation was done primarily through collecting. In the case of the latter, the birds were shot and skinned. For the former, moths are caught, killed and pinned. There are still some collectors out there, but there is beginning to be a shift to observing and releasing living individuals – the equivalent of birders relying on their binoculars instead of their shotguns.
The downside to this is that most of the printed guides that currently exist for moths are of spread specimens, dead individuals that have been pinned for a collection with their wings open and spread as in flight. Although this is great for seeing all of the wing, except perhaps in the case of a few groups (the geometers, for instance, or some of the silk moths) most of the moths you encounter don’t hold their wings spread open like that when alive. This makes identifying them from current guides a bit of a challenge (our new guide will be the first printed guide to present a comprehensive selection of moths from this region as live specimen photos, but unfortunately it won’t be out till 2012).
But if most moths are a challenge, the Marathyssas may be darn near impossible. This is because, as you can see in the photo above, they rest with their wings tightly furled, concealing most of the field marks one would reference in looking at spread specimens. On the other hand, this resting posture is itself a very valuable field mark, as only the Light Marathyssa above and its very similar sister species the Dark Marathyssa sit like this. This photo doesn’t show it, but they often curl their abdomen into the air, as well.
The species is found through most of the east, from Maine to Texas. Although the Dark flies through much of the year, the Light is really just restricted to the spring. Interestingly, the larvae of the Light Marathyssa feed on poison ivy. I wonder if they, in ingesting the oils, take on some of the same rash-inducing properties as the vine?