Ilia Underwing
Catocala ilia (Cramer, 1775)
Family: Erebidae
Status: Resident
Range: Found across the continent but scarce to absent from the Dakotas through Kansas west to the Pacific Coast states where it once again becomes more numerous.
Larval Hostplant(s): Oaks (Quercus)
NENHP Ranking: Not listed
Broods/Flight Times: A single extended summer brood, June into September.
Habitat: Deciduous woodlands.
Avg. Wingspan: Large size, 2 1/2 – 3 1/4 Inches.
Found at: Indian Cave Stae Park, Fontenelle Forest, Niobrara Valley Preserve
Overwintering: As eggs on tree bark.
Identification: FW color varies from grayish-brown to completely black; forewing usually with some whitish in median area; reniform spot usually outlined with white (or solid white in form “conspicua”); AM line broad, black, and relatively straight, contrasting against paler median area; HW median band reddish-orange or dark pink with deep scallops near anal angle; HW fringe pale orangish, narrow except at the apex. (1)
Similar Species: The Betrothed Underwing (C. innubens) has a paler HW ground color(2). Umber Underwing (C. umbrosa) forewing lacks conspicuous white outline around reniform spot. Aholibah Underwing’s (C. aholibah) HWs are darker, a deep red with a slight purple tint. (1). The reniform spot and HW fringe should differentiate this moth.
Notes: This moth sometimes rests with wings partly open, revealing parts of the HWs two colored bands and two black bands. Identifying features illustrated.
Literature Cited: (1) BugGuide.net, (2) Sargent, T. D. 1976 Legion of the Night. The Underwing Moths, Univ. Mass. Press; Amherst; 222 pp.
🔗Links: Moth Photographers Group, BugGuide.net
