Callosamia promethia
"Promethia Moth, Spicebush Silkmoth"
Family: Saturniidae

The Promethia Moth commonly referred to as the Spicebush Silk Moth, can be found in deciduous woodlands and ranges from Southern Quebec, Wisconsin, Minnesota, the Florida Panhandle to the Gulf Coast into East Texas. There is very little sexual dimorphism with the males and females having a wingspan of 7.5 cm to 9.5-cm. There are, however, differences in coloration. Males are usually black or a reddish hue and the females are brown during the spring brood and reddish during the summer broods. The two broods occur from May to July in the north and from March to May in the south. The Spicebush Moth goes through three developmental stages. The first stage is called the ova (egg) and is off-white to tan in color. It usually takes 14 to 20 days to hatch but in warmer weather the time decreases.

The second stage is the larva which can vary in color. The larva start off with small dots and stripes, then change to all stripes, then to all white, and finally to white with red tubercles or with bright red or orange thoracic tubercles and a yellow caudal tubercle. The larvae feed in large groups. They have a tremendous appetite which provides energy during the pupal stage. As their name implies, the main food source is the spicebush but they will also feed on leaves of sassafras or wild cherry. When fully grown, the larva spins a cocoon inside a wrapped leaf and prepares to pupate where it will metamorphosis to the adult.

As adults, Spicebush Moths do not feed. The adult males are not attracted to light and are usually seen flying late in the afternoon into the early evening. This is also when mating occurs. Mating takes place during the late afternoon and early evening. Males and females mate readily and remain coupled until the next evening. Males have the ability to fly over 20 miles per day. After mating, males and females separate, leaving the female to lay her eggs to begin another generation.

Brian E. Gibson
Sarah Shelly
Insect Biology and Diversity – Fall 2003