Saturniinae

Distinguished from other Saturniidae subfamilies by the combination of large size, prominent eyespot patterns on wings, and adult mouthpart reduction. The five tribal groups can be differentiated by geographic distribution and morphological traits: Attacini (atlas moths and relatives, largely Oriental and Palearctic), Saturniini (typical emperor moths including moon moths with tailed hindwings), Bunaeini and Micragonini (African tribes, now confirmed as part of Saturniinae rather than a separate subfamily), and Urotini. Species-level identification relies on wing pattern details, presence or absence of hindwing tails, and geographic origin.

Medium to very large moths with adult wingspans ranging from 7.5 to 15 cm, occasionally exceeding this range. Wings typically display prominent eyespots on the upper surface, varying from realistic eye-like markings to crescent moon or angular shapes; some species have transparent windows where wing scales are reduced or absent. Sexual dimorphism is pronounced in some species: females may weigh nearly double that of males, with larger body size and wings. Males possess broad wings and streamlined bodies with large, feathery antennae adapted for detecting pheromones; females have smaller, less elaborate antennae.

Forest habitats worldwide, with highest diversity in the Neotropics (Mexico, Central and South America). Specific habitat associations vary by tribe and species: hill-distributed species in Taiwan and East Asia are closely related to southern China and Southeast Asian taxa, while high-altitude populations (>1,500 m) in Taiwan have sibling species in temperate Northeast Asia. Many species are associated with specific host trees for larval development.

Worldwide distribution with major centers of diversity in the Neotropics, tropical Asia, and Africa. Includes species from India to Hong Kong, Taiwan, Indonesia, sub-Saharan Africa, and North America (e.g., Hyalophora cecropia ranging from Canada to Florida). Taiwanese endemic species demonstrate repeated colonization from mainland Asia via land bridges during Pleistocene glaciations.

Adult emergence typically occurs in spring and summer months; timing varies by species and latitude. Cecropia moths emerge with warm weather and tender leaf availability. Hubbard's silkmoth is active June–September, peaking in July–August, with possible multiple generations in Texas extending to November. Most species have one generation per year.

Adults do not feed; larvae are folivorous, feeding on leaves of trees, vines, and shrubs. Host plant associations vary widely: moon moths (Argema, Actias, Graellsia) specialize on resinous hostplants; Cecropia larvae feed on more than twenty plant species including various trees and shrubs. Hubbard's silkmoth larvae feed on Catclaw Acacia, Honey Mesquite, and Little-leaf Palo Verde, and will accept alternate hosts including Honey Locust and Black Locust in captivity.

• Trees and shrubs (general) - larval food plantWide variety of host plants across genera
• Resinous hostplants - larval food plantSpecialized association of moon moths (Argema, Actias, Graellsia)
• Acacia greggii - larval food plantCatclaw Acacia for Hubbard's silkmoth
• Prosopis glandulosa - larval food plantHoney Mesquite for Hubbard's silkmoth
• Cercidium microphyllum - larval food plantLittle-leaf Palo Verde for Hubbard's silkmoth

Eggs are oblong and laid flat in clusters against each other. Larval period lasts approximately 78 days, typically passing through five instars (though some species have more). Caterpillars are large and heavy at maturity, with some approaching the size of a frankfurter. Pupation occurs in a silk cocoon, often yellowish in color and resembling a small wooden barrel in shape; cocoons may be attached to vegetation or formed underground in shallow cells. Adults emerge and live 5–12 days without feeding.

Adults are primarily nocturnal, with the exception of males in four subfamilies. Males use large, feathery antennae to detect female sex pheromones and may follow scent trails for a mile or more. Females typically remain near their cocoons after emergence, investing energy in egg production rather than flight, and emit species-specific pheromones to attract males. After mating, females fly to host trees to deposit eggs; unmated females may also deposit eggs in large quantities. Larvae of some species feed nocturnally. Some species exhibit poor flight capability despite large body size.

Larvae function as significant herbivores in forest ecosystems, consuming substantial quantities of foliage. Adults serve as prey for bats and other nocturnal predators. The subfamily represents a major component of Lepidoptera diversity in tropical and temperate forests.

Important source of wild silk in many cultures; cocoons harvested for silk production and for ceremonial items such as ankle rattles. Some species used as human food. Subject of increasing interest in captive breeding as a hobby and cottage industry. Threatened by habitat loss, suburban sprawl, light pollution, and introduced parasitoids such as Compsilura concinnata, which has reduced or extirpated populations of some North American species.

• Other Saturniidae subfamiliesSaturniinae distinguished by combination of large size, eyespot wing patterns, and adult mouthpart reduction; other subfamilies may lack these features or have different geographic distributions
• Sphingidae (hawk moths)Both contain large species with streamlined bodies, but Sphingidae adults have fully developed proboscis for nectar feeding and lack the prominent eyespot patterns characteristic of Saturniinae

• silkmoth
• giant moth
• wild silk
• forest moth
• nocturnal
• eyespot
• moon moth
• atlas moth
• luna moth
• cecropia moth

• BugGuide
• Wikipedia
• iNaturalist taxon
• NCBI Taxonomy
• Catalogue of Life
• See Silkworm Moths and Silk at the Bohart Museum of Entomology Open House | Bug Squad
• A season of silk moths continues with Cecropia moth, Hyalophora cecropia — Bug of the Week
• Bug Eric: Giant Silkmoths
• Bug Eric: Artistic License
• Bug Eric: Moth Monday: Hubbard's Silkmoth
• Bug Eric: Coming Soon: National Moth Week
• Monophyly, composition, and relationships within Saturniinae (Lepidoptera: Saturniidae): Evidence from two nuclear genes
• Cecropia Moth, Cecropia Silk Moth, Robin Moth, Hyalophora cecropia Linnaeus (Insecta: Lepidoptera: Saturniidae: Saturniinae: Attacini)
• Differentiation patterns of emperor moths (Lepidoptera: Saturniidae: Saturniinae) of a continental island: divergent evolutionary history driven by Pleistocene glaciations