Antheraea polyphemus

Polyphemus moths, Antheraea polyphemus, can be found in all of the continental United States except Arizona and Nevada and in every Canadian province except Newfoundland and Prince Edward Island. ("Polyphemus Moth", 2005; "Polyphemus Moth", 2005)

Polyphemus moths inhabit deciduous hardwood forests, urban areas, orchards, and wetlands. ("Polyphemus Moth", 2005; "Polyphemus", 2007)

Polythemus moths, as caterpillars, are bright green with a reddish brown head. They have 6 orange tubercles and bristles on each segment of their body. Each abdomen segment has a slanted yellow line that is purple-brown in color. Caterpillars can grow to about 7 cm in length.

As adults, members of this species are large moths. Polythemus moths have a hairy body, and adults can vary from red-brown to dark brown in color. Each hind wing has a large yellow “eyespot” lined with blue and black. The center of this eyespot is uniquely transparent. The front wings have a smaller yellow spot. The margin of both the front and hind wings has a black and white stripe. Wingspan ranges from 10 to 15 cm. Whereas adult males have bushy antennae for detecting pheromones, females have slender antennae.

Polyphemus moth caterpillars greatly resemble caterpillars of luna moths. While polyphemus moths have single horizontal lines along each side of the body, luna moths have vertical yellow lines on each segment. ("Polyphemus Moth", 2005; Hyche, 2000; "Polyphemus Moth", 2005; Hyche, 2000; "Luna, Io, Imperial, Cecropia, Polyphemus Moths", 1999)

After about 10 days, tiny polyphemus moth caterpillars hatch from eggs. Larvae (caterpillars) molt 5 times and grow to their full size in 5 to 6 weeks. When caterpillars are fully grown, they wrap themselves in a leaf and build a cocoon out of silk. Cocoons are oval in shape, 40 mm in length and 22 to 24 mm in diameter. While in a cocoon, a caterpillar develops into a pupa and then emerges as an adult moth in about 2 weeks. Polyphemus moths can also overwinter in their cocoons, which increases time as pupae. (Hyche, 2000; Mackinnon, 2007; Vaughn, 2006)

Popyphemus moths mate the same day that they emerge from their cocoons, and mating usually occurs during late afternoon. Females emit pheromones, which can be detected up to a mile away, to attract mates. Mating of saturniids can last from less than an hour to many hours. Females lay their eggs shortly after mating. If unsuccessful in recruiting a male after 2 or 3 days, females stop calling and release their unfertilized eggs. ("Polyphemus Moth", 2005; Day, 2007; Hyche, 2000; "Polyphemus", 2007)

Female polyphemus moths begin to emerge and mate during early spring. Females lay up to 5 eggs singly or in groups of 2 or 3 on the underside of tree leaves. Eggs are flat and round, cream to light tan in color on top with a brown outline, and are about 1.25 mm thick and 3 mm in diameter. In most regions, 2 broods of polyphemus moths hatch per year; one hatches in early spring and the other in late summer. However, in the northernmost part of their range, only one brood hatches per year. In the southern part of their range, many broods may hatch each year. (Day, 2007; Day, 2007; "Polyphemus", 2007; "Luna, Io, Imperial, Cecropia, Polyphemus Moths", 1999)

Female polyphemus moths usually lay their eggs on leaves that are a good food source for the caterpillars. They are not otherwise involved in the rearing of their offspring. ("Polyphemus Moth", 2005)

As adults (moths), polyphemus moths live a maximum of only 4 days. Their entire life cycle averages about 3 months in length. This includes about 10 days as eggs, 5 to 6 weeks as larvae, 2 weeks as pupa, and about 4 days as adults. If they overwinter as pupa, this life cycle increases in length. (Vaughn, 2006)

Adult polyphemus moths are nocturnal. Adult males can only fly at temperatures above 7˚C. Larvae are solitary and, in captivity, crowding of Saturniids leads to decreased growth and increase likelihood of disease transmittance. (Mackinnon, 2007; Oehlke, 2005; Tuskes, et al., 1996)

Little information is available regarding the home range of polyphemus moths.

When ready to mate, female polyphemus moths emit pheromones that attract males. Males use their sense of smell and touch to find females. Although larvae (caterpillars) have eyes, they are small and primitive, resulting in poor vision. (Cook, 2004; Day, 2007; Hyche, 2000; Oehlke, 2005)

Caterpillars feed on leaves of broad-leaved trees and shrubs such as sweetgum (Liquidambar), birch (Betula), grape (Vitis), hickory (Carya), maple (Acer), oak (Quercus), willow (Salix), and members of the rose family (Rosaceae). Larvae also eat their egg shells after hatching and their freshly molted skin. A caterpillar eats 86,000 times its body weight. Adult moths have a reduced mouth and do not eat. ("Polyphemus Moth", 2005; Day, 2007)

Polyphemus moth caterpillars are preyed upon by yellowjackets and ants. They are also parasitized by wasps. Larvae and pupae are consumed by raccoons and squirrels. The green coloration of caterpillars makes them difficult to spot. Adults also practice mimicry; they have eyespots on their hind wings. (Cook, 2004; Day, 2007; Hyche, 2000; Cook, 2004; Day, 2007; Hyche, 2000)

Polyphemus moths act as prey for certain insects, raccoons, and squirrels. They are also parasitized by some wasps. Because they consume a large quantity of leaves, they may also considerably contribute to nutrient cycling. (Day, 2007; Hyche, 2000)

There are no known direct positive effects of polyphemus moths on humans, though many are hand-raised by curious individuals. (Tuskes, et al., 1996; Day, 2007; Tuskes, et al., 1996)

Polyphemus moth caterpillars are occasionally considered pests to plum orchards in California. ("Polyphemus Moth", 2005)

Polyphemus moths have not been evaluated or are not considered threatened by the IUCN, US Fish and Wildlife Service or CITES.

Polyphemus moths are so named for the large eyespots on their wings. They are named after the Greek myth of the Cyclops, Polyphemus. ("Polyphemus Moth", 2005; Cook, 2004; Tuskes, et al., 1996)