Giant Silk Moths Are Fascinating To See Firsthand

Supersized moths — Luna and Polyphemus — are amazing to discover!

These Silk Moths Make A Big Impression

The end of July is National Moth Week. Seems a perfect time to share two extraordinary silk moths seen here on Amelia Island, Florida (in the family Saturniidae) — Luna and Polyphemus.

Luna Moths (A.K.A. “Moon Moths”)
Luna (A.K.A., American Moon Moth), photographed on Amelia Island, Florida.
Luna (A.K.A., American Moon Moth), photographed on Amelia Island, Florida.

A memorable line in the famous Snow White fairy tale by the German Grimm brothers dates back to the year 1812 — “Mirror, mirror on the wall, who in this land is fairest of all?”

If the dark emotion of jealously could be felt within the nocturnal flying insect world, a target of the “green-eyed monster” would likely be Luna moths, renowned for their eye-catching beauty. Besides their enviable shade of lime green, Luna moths (Actias luna), are monster-sized, as well. Considered one of North America’s largest moths, the wingspan can range from 4 to 7 inches. Said to be named after a goddess (Luna, the Roman moon goddess), the short-lived Luna moth is such a treat to see!

Wide Wingspan, Short Life Span

After emerging from cocoons, Luna moths only live about 10 days to reproduce. During their short time as a beautiful moth, they seek a mate & lay eggs. Experts indicate the Luna moth doesn’t eat (they don’t have a mouth). Apparently “most adult moths don’t eat,” according to the U.S. Fish and Wildlife Service

Some advice by lepidopterist Andrei Sourakov of the Florida Museum of Natural History rings true: “You don’t have to venture into exotic places to make discoveries. Just look in your backyard.” 

The Luna seen here was inadvertently discovered while still in its pupa state. Without some curiosity, its identity would not have been revealed.

While in the yard several years back on a June day, a large pupa was found wrapped in a leaf on the ground. Having no idea what it was exactly, a jar was grabbed from the house, the “specimen” put inside and lid screwed on. Days later, a gorgeous Luna moth was found in the jar, much to our delight and astonishment. They certainly make a big impression!

Sweetgum Trees — A Host of The Luna Moth

After some research, we learned it was the presence of Sweetgum trees that created this local nature lesson. The lovely silk moth was carefully turned out of the jar at the tree roots, later to move up the tree (as shown in the image). Those with Sweetgum trees may like to take a closer look around in the future for a potential opportunity to find a Luna moth, pupa, or their caterpillar stage.

Besides Sweetgum, the University of Florida (UF) lists other tree species in the southern USA that also host Luna moths, as follows: “members of the walnut family Juglandaceae and hickories, sumacs (Rhus) and persimmon.”

Polyphemus Moth
Polyphemus moth (photo by, Fernandina Beach, FL). Named after the giant cyclops from Greek mythology.
Polyphemus moth (photo by, Fernandina Beach, FL).

Another big, amazing moth is the Polyphemus (Antheraea polyphemus), appropriately named after the giant cyclops from Greek mythology. According to the University of Florida (UF), the Polyphemus is another of the largest silk moths, with an approximate adult wing span of 4 to 6 inches. In the Sunshine State, “due to staggered emergence, adults may be found during every month of the year in Florida,” states published research by the UF. (The one pictured above was photographed on Amelia Island in the month of August back in 2016.)

End of July Is National Moth Week

According to a news release by the founding organization, National Moth Week (NMW) is a worldwide citizen science project that invites organizations and individuals of all ages and abilities to observe, document and appreciate moths for their diversity, beauty and vital environmental role as pollinators.

This year, the 12th annual National Moth Week (NMW) is being observed July 22-30, 2023. The organization aims to bring attention to their beauty, extraordinary diversity, and essential role in the natural world as pollinators and a food source for other creatures such as birds and bats.

Since its founding in New Jersey in 2012, National Moth Week (NMW) has inspired thousands of individuals and organizations in 117 nations to host or attend private and public mothing and educational events. Currently, 35 country coordinators on six continents encourage their citizens to observe moths and post their data with NMW partners like Project Noah and iNaturalist.

Learn more about National Moth Week and citizen science project by visiting the website of the organization that began this celebration of moths.

By W.B. Lawson

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