Cynthia Silkmoth

§ Quick facts

§ Encyclopedia

Samia cynthia, the ailanthus silkmoth, is a saturniid moth, used to produce silk fabric but not as domesticated as the silkworm, Bombyx mori. The moth has very large wings of 113–125 mm (4.4–4.9 in), with a quarter-moon shaped spot on both the upper and lower wings, whitish and yellow stripes and brown background. There are eyespots on the outer forewings. The species was first described by Dru Drury in 1773.

Source: Wikipedia — Samia cynthia · Licensed under CC BY-SA 4.0

§ Identification

Field marks. Adult males: dark chocolate-brown wings with pale band. Adult females: lighter brown with red-brown wings. Caterpillars: pale green with prominent red, blue, and yellow tubercles.

Similar species. Cecropia, Polyphemus, Luna Moths (other large silkmoths; different patterns).

Voice. N/A

§ Diet & behavior

Diet. Adults: do not feed. Larvae: sassafras, spicebush, wild cherry, tulip tree.

Behavior. Medium silkmoth of eastern North American forests. Females release pheromones at dawn; males fly during the day (unusual for silkmoths). Caterpillars build distinctive cocoons by rolling a single leaf and binding it with silk to a twig; the cocoon stays attached and overwinters with leaf still attached (looks like a dead leaf clinging to the tree).

§ Range

Native to Asia; introduced to North America

§ Habitat

Diverse: gardens, suburbs

§ Threats

In US: their preferred host plant (tree of heaven) is invasive.

§ Conservation status

According to the IUCN Red List, the cynthia silkmoth is currently classified as Least Concern.

§ What helps

In US: maintain biodiversity; don't plant tree of heaven.

§ Further reading

• Wikipedia — Samia cynthia
• www.nwf.org — authoritative profile of Samia cynthia
• iNaturalist · taxon 49266
• IUCN Red List — search for Samia cynthia
• GBIF occurrence records
• Encyclopedia of Life — Samia cynthia

§ Sources cited

• Butterflies and Moths of North America
• Xerces Society
• iNaturalist