Luna moth

Actias luna belongs to Saturniidae, the giant silk-moth family. Tropaea luna is an older combination for the same North American species. [1]

Adults have green wings, an eyespot on each wing and a long tail on each hindwing. The wingspan is approximately 75–105 mm. The comb-like antennae are larger in males. [1]

In populations with several annual generations, spring adults are deep green with reddish-purple wing margins; later broods tend to have more yellowish wings and margins. [1]

The luna moth inhabits forested eastern North America, including parts of southern Canada and the eastern United States. It has one annual generation from Michigan northward, two in the Ohio Valley and three farther south. [1]

Caterpillars pass through five instars before spinning a silken cocoon among leaves. Autumn cocoons fall to the ground with the leaves. In an experiment with an Iowa egg batch, shorter daily light exposures favoured pupal dormancy, whereas longer exposures favoured direct development. [1][2]

An emerging adult cuts through its cocoon using serrated structures near the bases of the forewings. These structures provide an exit after the moth has shed the pupal skin. [1][3]

Adults have reduced mouthparts and do not feed; their energy comes from resources accumulated as caterpillars. Larval hosts vary geographically: white birch is important in northern populations, while southern populations use plants including walnuts, hickories, sumacs, sweetgum and persimmon. [1]

Lindroth tested newly hatched larvae on eleven plants. Survival was very poor on seven, while larvae performed well and similarly on birch, walnut, butternut and hickory. [4][1]

Females attract males with a sex pheromone. A 2016 study linked compounds from female gland extracts to male antennal responses, then demonstrated attraction to synthetic blends in field trials in Ontario and Kentucky. [5]

In 2015 experiments with big brown bats, the spinning hindwing tails redirected attacks away from the moth’s body. Moths with intact tails survived more attacks than moths whose tails had been removed. [6]

Later tail-manipulation experiments examined how different tail forms affected escape success. Together, these studies identify the tails as part of an acoustic defence against echolocating predators. [7][6]

A daytime experiment tested whether the conspicuous tails increased vulnerability to Carolina wrens. Models made with real luna-moth wings received no greater detection or attack when tails were present. [8]

Linnaeus assigned the epithet luna in 1758, following earlier descriptions of the moth. The lunar name also features in its cultural history: the species appeared on a United States postage stamp in 1987. [1]

Spread-wing views expose all four eyespots and the long hindwing tails. A folded-wing view shows how the broad wings overlap while the narrow tails project beyond them.

The compositions explore the luna moth’s green wings, eyespots and trailing hindwing outline through spread-wing, resting and flight poses.

Keep the enclosure closed and display it in indirect light, away from heat and damp conditions. Handle the frame by its edges and clean only its exterior according to the maker’s instructions.

Does the adult feed? No. Adult luna moths rely on energy stored during caterpillar development. [1]

What do the tails do? Their movement can divert the attacks of echolocating bats, as demonstrated in controlled predator trials. [6]

How many generations occur each year? The number increases southward, from one in the northern part of the range to three in parts of the southern United States. [1]

The IFAS account covers identification and regional life history. Original studies examine pupal dormancy, cocoon emergence, host suitability, pheromone attraction and the effects of hindwing tails during predator encounters. [1][2][3][4][5][6][7][8]