By Steve Mace
This past Sunday while I was botanizing in Lawrence County, Kentucky, I spotted my first of the season Falcate Orangetip, my favorite butterfly.
The life history of this species is as interesting as it is beautiful. Thirty-eight of the last 40 years of my life was spent in Mason County, West Virginia so I’ll speak of my experiences there.
I’d usually start seeing them there the last week of March. By the 10th of May, they were gone. Usually I’d see them along the moister areas along streams and ponds. The reason being, and I’m only guessing here, is that’s mainly where the host plants grow that their larvae eat. Females lay a single egg on the flowers of species from the mustard family, the cutleaf-toothwort seemingly to be their favorite. Each female lays more eggs, but just one on each plant. The larva mainly eat flower buds, flowers, and developing seeds. And, if by chance another female lays an egg on an already occupied plant, larger larva have been known to eat the smaller. I don’t know if they do this as a food source or to reduce competition for the food supply.
The cutleaf-toothwort is a spring ephemeral, meaning quickly fading. This species does its thing early, before the trees leaf out so as to get as much sunshine they can. By mid-May here, the tree leaves have formed their canopy and very little sunlight reaches the forest floor. The cutleaf-toothwort is now in its declining days, holding on for another month for the seeds to mature.
So I suppose this is why this butterfly species lifespan is so short. With the larvae host plants growing season limited, there’s no need for Falcate Orangetips to continue into summer. There would be no food source for the larvae. Anyway, the larvae pupate by mid-June and develop until next spring at which time the species again flutter about in our leafless forests. Interesting enough, some don’t emerge until the 2nd or 3rd spring. I have no idea why.
Occasionally I’ll see males on dry ridge tops. I can only surmise this is done in search of females. I saw two males this past Sunday on a ridge top in Lawrence County, Kentucky and a female in Ritter Park in Huntington, West Virginia.