Bagworm moths

Definition

A family (Psychidae) of moths whose larvae construct portable, silken cases reinforced with plant debris, soil, or other materials, carrying them throughout development. Females are typically wingless and remain in the case, while males are winged and disperse to mate. The larval architecture and extreme sexual dimorphism make the group distinctive among Lepidoptera.

Etymology

From the larval habit of constructing bag-like portable cases.

Example

Thyridopteryx ephemeraeformis, the evergreen bagworm, is a North American pest whose larval cases incorporate host-plant needles and can defoliate conifers and broadleaf trees when populations are high.

Synonyms

• Psychidae
• case moths

Related Terms

• Lepidoptera
• larval case
• Sexual dimorphism
• Thyridopteryx ephemeraeformis
• portable shelter

Usage Notes

The common name refers specifically to family Psychidae, not to a single species. "Case moth" is sometimes preferred in regions where "bagworm" causes confusion with unrelated bag-shelter caterpillars (Lepidoptera: Ochrogaster). Larval cases are often mistaken for plant galls or small cones. Identification to species usually requires rearing males or examining larval case architecture and plant association.