Aseptis binotata

Distinguished from other Aseptis species by its exceptional variability in forewing color and pattern strength. The combination of the large pale postreniform patch (in dark forms), convex antemedial line with light tan fill, and presence of a short black basal dash helps separate it from congeners. The black wedges near the outer margin below the apex and outlined forewing spots are additional diagnostic features. Pale specimens may require careful examination of remaining dark markings.

Adults have a wingspan of 29.5–35 mm. Forewing coloration is highly variable, ranging from brownish, warm dark brown, pale to medium gray brown, yellowish light brown, to reddish brown depending on locality. Dark specimens display a large pale yellowish postreniform patch bisected by the dark postmedial line. The antemedial line is strongly convex laterally and filled with light tan. Black markings include a series of wedges near the outer margin below the apex, outlines of the three forewing spots, and in most specimens a short black basal dash. Pale specimens may appear washed out or have contrasting dark markings. Larvae are green with a white and red lateral stripe.

Occurs from sea level to elevations exceeding 2000 meters. Found in diverse habitats including dense forest and shrub desert, indicating broad ecological tolerance.

Widespread in western North America, west of south-central Alberta, Wyoming, and Nebraska. Along the Pacific Coast, ranges from northern Mexico to south-central British Columbia.

Flight period varies with latitude and elevation. In the south, flight begins in March at low elevations and continues April through July in mountainous areas. In the north, flight begins later and extends into August.

Larvae feed on various broadleaf trees and shrubs. Recorded host plants include big-leaf maple (Acer macrophyllum), ocean spray (Holodiscus discolor), and Ceanothus species. Additional recorded food plants include Oemleria, Symphoricarpos, and Ribes species.

• Acer macrophyllum - larval food plantbig-leaf maple
• Holodiscus discolor - larval food plantocean spray
• Ceanothus - larval food plantmultiple species
• Oemleria - larval food plant
• Symphoricarpos - larval food plant
• Ribes - larval food plant

Complete metamorphosis with egg, larva, pupa, and adult stages. Larval stage is green with a white and red lateral stripe. Specific details on pupation site, number of generations, and overwintering stage are not documented.

Larval herbivore on broadleaf trees and shrubs; contributes to nutrient cycling and serves as prey for parasitoids and predators.

• Other Aseptis speciesAseptis binotata is distinguished by being the most variable in forewing color and pattern within the genus; specific markings (postreniform patch, antemedial line shape, black basal dash) aid separation

• western North America
• variable coloration
• broadleaf feeder
• elevation generalist

• BugGuide
• Wikipedia
• GBIF taxonomy match
• iNaturalist taxon
• NCBI Taxonomy
• Catalogue of Life
• How One Entomologist Puts Communication and Policy Training Into Action in Pesticide Safety Education
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