I rest my chin on the wooden ledge of our huge picture window, nose pressed against the cool glass. Mom concentrates on her needlework while Dad snores on the living room floor, “watching” television. Insects with fascinating patterns on their undersides cling to the window, beguiled by the flickering glow of TV Western mixed with lamplight. A ghostly green shape flutters and lands in front of my eyes. It has a fuzzy belly and large leaf-shaped things on its head. Long graceful tails hang from wings that are almost as big as my hands. I gasp and quietly tap my finger on the glass. “Mommy! LOOK!” My mother’s eyebrows arch high above her thin black reading glasses. She smiles. “Ohhh, isn’t that gorgeous! That’s a Luna Moth! See the little moons on its wings?”
The Luna Moth is one of the largest moths in North America, and a member of the Giant Silkworm family. Its 3 to 4-1/2 inch wings are pale green with transparent eyespots and long curving tails on its hind wings. It has a white velvety body, pinkish legs and feathery antennae.
At around midnight, the Luna moth’s “calling time,” the males’ larger ultra-sensitive antennae begin to detect species-specific pheromones released by females. Although females usually don’t fly until after mating, males will fly great distances to follow the scent of a female. "Calling” usually continues until the female has mated. The following evening after the pair separates, the female lays about 200 eggs in small clusters on the leaf undersides of host plants such as walnut, hickory and persimmon.
Larvae emerge in about one week and soon become bright green caterpillars with a narrow yellow stripe, spiny reddish tubercles and a brownish head. Sedentary, solitary feeders, they will grow quite large. After storing enough energy to sustain themselves through their adult mating and egg-laying stages, Luna caterpillars use leaves and silk to spin papery brown cocoons. These can always be found in leaf litter below host plants. In Missouri, three generations of Luna moths are usually produced each year. The third brood will over-winter in cocoons until the following April.
Luna moths die shortly after mating or laying eggs. Adults don't eat -- they have no mouthparts. Luna moths must accomplish their life's work in about one week. Short life span and night flying habits combine to make them a rare and exciting discovery.
Five decades have passed since I saw my first Luna moth. My mother and father - as if seen through cool windowpane– are with me in memory as I watch for the Luna to reappear every Spring. Its fragility and ephemeral beauty still takes my breath away.
