Saturniidae

Definition

A family of Lepidoptera comprising the giant silk moths, royal moths, and emperor moths, characterized by large body size, broad wings, reduced or absent mouthparts in adults (which do not feed), and complete metamorphosis with caterpillars that often bear prominent tubercles or spines. The family contains some of the largest moth species worldwide, with wingspans exceeding 15 cm in genera such as *Attacus* and *Thysania*.

Etymology

From the genus *Saturnia* (itself from Latin Saturnus, the Roman god) + -idae (family suffix)

Example

The luna moth (*Actias luna*) and cecropia moth (*Hyalophora cecropia*) are familiar North American saturniids whose adults lack functional mouthparts and survive on larval fat reserves for their brief reproductive lifespan.

Synonyms

• giant silk moths (informal collective)
• saturniids (vernacular)

Related Terms

• Lepidoptera
• Bombycoidea
• Saturniinae
• giant silk moth
• emperor moth
• Spinneret
• Ecdysis
• complete metamorphosis

Usage Notes

Saturniidae is placed in the superfamily Bombycoidea (series Saturniiformes) and comprises approximately 2,300 described species across multiple subfamilies including Saturniinae, Ceratocampinae, and Hemileucinae. Adults are frequently attracted to light and are important subjects in ecological studies of adult longevity without feeding; larvae are often economically significant as defoliators of forest trees. The family is distinguished from related Bombycidae (silkworm moths) by adult non-feeding and generally larger size. Some classifications recognize additional subfamilies; the family's circumscription has remained relatively stable.