Acronicta dactylina
The genus Acronicta comprises the moths known as "daggers"
on account of a dagger-shaped mark that is more or less prominent on the forewings
of the many species. (76 were listed for North America in 1983, and there are
yet more in Europe and Asia.) The adult moths are quite similar to each other,
and are not easy to identify, and one may even doubt that many of them are full
species. All doubt is removed, however, on seeing the caterpillars, for there
is a wonderful variety of striking caterpillars; the caterpillars of two almost
indistinguishable adults may be quite different in appearance. That of dactylina
feeds in August on alder, and overwinters as a pupa in a parchment-like cocoon,
which is too tough to be torn apart by hand. The moths appear the following
June. The genus in the past has been called Apatele or Apatela.