from The Century Dictionary.
- noun A genus of agaristid moths containing several species which inhabit the United States. One of them, A. octomaculata, occurs abundantly in the larval state upon grape-vines, which it injures by devouring the foliage.
Sorry, no etymologies found.
But the most interesting new visitor was this moth known as an Eight-Spotted Forester, aka an alypia octomaculata fabricius, if I am to trust the various identification guides I checked.