Tawny Emperor

Asterocampa clyton — the tawny emperor — is one of about 5 species in genus Asterocampa (the 'emperor' butterflies of North and Central America — all closely associated with hackberry trees as larval host plants) and the SISTER SPECIES to the hackberry emperor (Asterocampa celtis — already in the Wild Files). The species is widespread across eastern and central North America from southern Ontario south through the eastern US to northern Florida and west to the Great Plains, with distribution largely overlapping the hackberry emperor's range (the two species commonly co-occur in the same hackberry-rich habitats and are often seen together on the same hackberry trees). Adults are 5-7 cm wingspan with the species' diagnostic features that distinguish from the hackberry emperor: warmer ORANGE-AND-TAN COLORATION with less prominent dark markings on the upperside (compared to the more brown-and-tan hackberry emperor) and SOLID UNDERSIDE EYESPOTS (the eyespots on the hindwing underside are simple solid dark spots without the concentric ring patterns characteristic of the hackberry emperor's eyespots). The two species are otherwise very similar in appearance, behavior, and habitat — both are restricted to forests where HACKBERRY TREES (Celtis occidentalis and related Celtis species) grow as the only known larval host plants. Both species exhibit the famous adult HUMAN-SWEAT-LANDING BEHAVIOR (see hackberry emperor for detailed description) — adults are strongly attracted to human sweat and other body secretions, and tawny emperors often join hackberry emperors on the same human in eastern NA forests, drinking salt-and-protein-rich fluids together. Adults of both species are also commonly attracted to other mud-puddling sources — animal urine and feces, decaying fruits, sap flows, salt-encrusted surfaces. Larvae feed exclusively on hackberry leaves and pupate on the underside of hackberry leaves, similar to the hackberry emperor. Tawny emperor adults emerge in mid-summer (typically a week or two later than hackberry emperors in the same locality) and live 1-2 weeks during peak summer flight season. The species is one of the most-encountered butterflies in eastern NA hackberry forests after the hackberry emperor, and the two species' shared human-landing behavior makes them familiar to outdoor recreationists in eastern NA. The species is harmless to humans (no venom, no bite — sweat-landing is harmless) and is a flagship sister species to the hackberry emperor in modern textbook discussions of NA butterfly biology.