Butterflies and Moths of North America

collecting and sharing data about Lepidoptera

Modest sphinx
Pachysphinx modesta (Harris, 1839)


Family: Sphingidae
Subfamily: Sphinginae
Identification: Upperside of forewing is gray with the basal third lighter; sometimes the outer third also is light, leaving just the median band dark. Upperside of hindwing is gray with a crimson patch and an inward-pointing blue-black triangle near the outer margin.
Wing Span: 3 - 4 11/16 inches (7.6 - 12 cm).
Life History: Females lay eggs on leaves of the hosts, and the eggs hatch in about 9 days. Fully-grown caterpillars pupate and overwinter in shallow burrows in the ground.
Flight: . One brood in the north from June-July, two broods in the south from May-September.
Caterpillar Hosts: Poplar, aspen, and cottonwood (Populus) and willow (Salix).
Adult Food: Adults do not feed.
Habitat: Riparian areas and moist mountainsides.
Range: Maine south to north Florida; west to Washington, Oregon, Utah, New Mexico, and Texas. Also Baja California Norte.
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