Bistonini

Distinguished from Boarmiini by retention of more plesiomorphic traits, including less specialized genitalia and wing venation. The combination of large size plus dense hairiness separates most Bistonini from typical geometrids; however, this resembles some Arctiidae, requiring careful examination of antennae (filiform in Bistonini, often bipectinate in Arctiidae) and wing coupling mechanism. Females of some genera (e.g., Alsophila, Orgyia relatives) may be larviform and flightless.

Large-bodied and conspicuously hairy by geometer moth standards. Wings typically broad with relatively simple patterning. Body pilosity pronounced, creating superficial resemblance to certain Arctiidae (tiger moths). Sexual dimorphism common, with females often flightless or brachypterous in some species.

Primarily associated with temperate and boreal forest ecosystems. Larval hosts are predominantly woody plants. Specific habitat associations vary by genus; some species occupy early successional habitats while others persist in mature woodlands.

Holarctic distribution predominant, with greatest diversity in temperate Eurasia and North America. Some genera extend into subtropical regions. The tribe is notably less diverse in tropical regions compared to related Boarmiini.

Adult activity concentrated in early spring for many species (e.g., Agriopis leucophaearia, Paleacrita vernata), with some extending into late autumn. Phenology closely tied to host plant budburst and senescence patterns.

• Deciduous trees and shrubs - larval food plantBroad range of woody angiosperms; specific associations vary by species
• Conifers - larval food plantSome species utilize gymnosperms

Adults of many species are nocturnal and attracted to light. Females of some genera are flightless, releasing pheromones from elevated substrates to attract males. Larvae are external feeders on foliage, typically solitary.

Larvae function as generalist folivores on woody vegetation, contributing to nutrient cycling in forest ecosystems. Population outbreaks can cause noticeable defoliation of host trees, though typically not at economically damaging levels.

Spring cankerworm (Paleacrita vernata) and fall cankerworm (Alsophila pometaria, related tribe) are occasional nuisance species in urban areas due to larval defoliation of shade trees. Some species (e.g., Biston betularia) have served as classic study organisms in evolutionary biology, though the peppered moth is now placed in a different tribe.

• BoarmiiniClosely related and sometimes merged; distinguished by more derived morphological features and generally smaller, less hairy body form
• Arctiidae (Erebidae: Arctiinae)Convergent resemblance in hairy, large-bodied species; distinguished by wing venation, tympanal organ position, and larval setal characteristics
• EranniniSometimes included within Bistonini; when separated, distinguished by more specialized genitalia and reduced wing pattern elements

• geometridae
• ennominae
• holarctic
• forest moths
• spring emergence
• flightless females

• BugGuide
• Wikipedia