Catocala ilia

Cramer, 1776

Ilia Underwing, Beloved Underwing, Wife Underwing

Species Guides

Catocala ilia zoe(Ilia Underwing)

Catocala ilia is a in the Erebidae, first described by Pieter Cramer in 1776. The is notable for its highly variable forewing patterns and strikingly colored hindwings, which are typically concealed at rest. It occurs across eastern North America with a disjunct in the southwestern United States represented by a distinct .

Catocala ilia zoe by (c) Don Loarie, some rights reserved (CC BY), uploaded by Don Loarie. Used under a CC-BY license.

Catocala ilia P1170502a by
xpda. Used under a CC BY-SA 4.0 license.

Erebinae- Catocala ilia (Ilia Underwing) by Kristof Zyskowski & Yulia Bereshpolova. Used under a CC BY 2.0 license.

Pronunciation

How to pronounce Catocala ilia: //ˌkætəˈkeɪlə ˈɪliə//

These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.

Identification

The white-circled spot on the forewing distinguishes Catocala ilia from other Catocala . The hindwing color ranges from pale orange to deep red, with some geographic variation. C. i. zoe in California and Arizona tends toward darker, more reddish hindwings. Forewing patterns are extremely variable and unreliable for identification without the spot character.

Images

Habitat

Deciduous and mixed forests with oak presence; woodlands, forest edges, and suburban areas with mature oak trees. Elevation range extends from lowlands to moderate elevations in mountainous regions.

Distribution

Eastern United States from approximately the Great Plains eastward, north to southern Canada (Manitoba, Saskatchewan, Ontario, Quebec, Maritime provinces). Disjunct western in California and Arizona ( C. i. zoe).

Seasonality

fly from June to September, with peak activity varying by latitude and local climate. In Colorado, has been recorded in late July.

Diet

Larvae feed on oak (Quercus), including black oak, bur oak, red oak, and white oak. feeding habits are not well documented; adults of related Catocala species have been observed feeding on tree sap and rotting fruit.

Host Associations

Quercus - larval plantMultiple oak including black, bur, red, and white oaks

Life Cycle

Complete : , larva, pupa, . Larvae are solitary feeders on oak foliage. occurs in soil or leaf litter. Adults are and attracted to light. stage not explicitly documented in sources.

Behavior

are strongly attracted to artificial light sources. When at rest, forewings are folded over the body, concealing the brightly colored hindwings—an apparent anti- . Adults have been documented visiting stations with fermented fruit mixtures.

Ecological Role

Larval stage functions as a folivore on oak trees, contributing to nutrient cycling. may serve as prey for including bats and owls. The bright hindwing coloration, flashed when disturbed, may startle predators (startle display).

Human Relevance

Subject of citizen science monitoring through National Week events. Occasionally encountered at porch lights. Not an agricultural or forest pest; larval feeding on oaks is not considered damaging at observed densities.

Similar Taxa

Catocala concumbensShares similar size and general underwing ; distinguished by different forewing spot pattern and hindwing coloration
Catocala amestrisOverlapping range in some areas; distinguished by forewing pattern details and hindwing color
Catocala delilahSimilar preferences; distinguished by forewing markings and geographic distribution

More Details

Subspecies

Two recognized: C. i. ilia (eastern North America) and C. i. zoe Behr, 1870 (California, Arizona). The western subspecies shows some differentiation in hindwing coloration.

Etymology

The specific epithet 'ilia' and 'beloved underwing' and 'wife underwing' suggest romantic connotations, though the origin is not explicitly documented in sources.