Butterflies and Moths of North America

collecting and sharing data about Lepidoptera

Io moth
Automeris io (Fabricius, 1775)


Family: Saturniidae
Subfamily: Hemileucinae
Identification: Upperside occasionally males from the spring brood will be mostly brown. Female forewings are brown or brownish purple to red and the bands and eyespots may or may not be apparent. Hindwings of both sexes are yellow to brownish orange with yellow or orange margins. Each hindwing has a large black and blue eyespot with a white dash in the middle.
Wing Span: 2 - 3 1/8 inches (5 - 8 cm).
Life History: Adults emerge during late morning or early afternoon, and mating takes place in the late evening. Females lay clumps of eggs on leaves or stems of the host plants. Young caterpillars feed together as a group and move in long "trains" while older caterpillars feed alone. Papery cocoons are spun in litter under the host plant or in crevices.
Flight: One brood in the north from May-June, two to three broods in the south from February-September, several broods throughout the year in the Florida Keys.
Caterpillar Hosts: A variety of plants including hackberry (Celtis), willow (Salix), mesquite (Prosopis), redbud (Cercis), currant (Ribes), blackberry (Rubus), and pear (Pyrus).
Adult Food: Adults do not feed.
Habitat: Deciduous forests, thorn scrub, and suburban areas.
Range: Maine west across southern Canada to southeastern Manitoba, the Dakotas, Nebraska, and Colorado; south to the Florida Keys, the Gulf states, Texas, and New Mexico; Mexico south to Costa Rico.
Conservation: Not usually required.
NCGR: G5 - Demonstrably secure globally, though it may be quite rare in parts of its range, especially at the periphery.
Management Needs: None reported.
Comments: NULL