Tinea pellionella

Difficult to distinguish from Tinea columbariella, Tinea dubiella, and Tinea svenssoni based on external morphology alone. Genitalia are diagnostic. Larval cases are distinctive: portable, cylindrical, and composed of silk plus incorporated food fibers—unlike the webbing constructed by Tineola bisselliella larvae. Adults lack the golden sheen of Tineola bisselliella and have more patterned forewings.

Primarily indoor environments: dwellings, outbuildings, warehouses, and wool stores. Associated with dark, undisturbed locations. Rarely found outdoors; restricted to temperate and cool Mediterranean climatic zones. In wool storage facilities, larvae occupy loose wool protruding through packaging breaches.

Cosmopolitan distribution, nearly worldwide in temperate regions. Native to Europe; now established across temperate zones globally. Documented from India, Australia, North America, and throughout Europe.

Adults typically encountered during summer and early autumn. In colder buildings, one generation per year with flight period April–October. In warmer buildings, multi-brooded with potential year-round activity. Population peaks in spring and summer in wool storage environments.

Larvae feed on fibrous keratin: wool, fur, feathers, hair. Also consumes detritus, cobwebs, bird nests (particularly domestic pigeon), stored vegetable produce, and wallpaper. Feeding experiments demonstrate larvae can only develop on foodstuffs of animal origin and metabolize cholesterol rather than phytosterols. Woollen materials impregnated with yeast support enhanced larval development.

Egg: Incubation 4–7 days depending on temperature (21.5–32.5°C); temperatures above 32.5°C lethal to eggs. Humidity does not affect incubation period. Larva: Development influenced by temperature and humidity; shortest development at 25°C and 90% relative humidity. Higher humidities shorten larval development regardless of temperature. Larvae construct and carry portable silken cases. Pupa: Pupation occurs within the larval case; pupal period 10.3–18 days depending on temperature (21.5–30°C); humidity has no effect. Adult: Emerges from case; does not feed. Sex ratio approximately 2.6 females:1 male. Three to four generations per year possible under favorable conditions (26°C, 82% RH, yeast-impregnated wool).

Larvae are strongly photophobic, avoiding direct sunlight and confined to dark situations. Damage to materials is significantly greater in continuous darkness than in alternating light and dark conditions. Larvae show no color preference in feeding, though specific dyes (Cloth fast orange G 4%) inhibit growth of newly hatched larvae. Adults fly around dusk, with peak activity in the three hours after sunset; activity increases with temperature. Females rarely fly, typically scurrying by foot. Males are attracted to female pheromones.

Decomposer of keratinous materials in natural settings; serious pest of stored animal products in human environments. Prey for spiders (notably Uloborus geniculatus in Australian wool stores) and parasitoids (Apanteles carpatus).

Economic pest of woollen textiles, carpets, furs, upholstery, and natural fiber products. Control measures parallel those for Tineola bisselliella: physical removal, chemical treatment, and biological control. Has become less common in UK homes with widespread central heating, which creates warmer, drier conditions less favorable to development.

• Tineola bisselliellaWebbing clothes moth constructs silk webbing rather than portable cases; adults have more uniform golden-bronze coloration without distinct forewing spotting; larvae do not carry cases.
• Tinea columbariellaExternally similar adult morphology; requires genitalia examination for definitive separation.
• Tinea dubiellaExternally similar adult morphology; requires genitalia examination for definitive separation.
• Tinea svenssoniExternally similar adult morphology; requires genitalia examination for definitive separation.

The common name "bagworm" is sometimes applied due to the larval case, but this causes confusion with Psychidae (true bagworm moths), which construct different types of portable cases. Association with bird nests has been suggested but not substantiated in large studies.

• pest
• stored product
• keratinophage
• synanthropic
• case-bearing larva

• BugGuide
• Wikipedia
• GBIF taxonomy match
• NCBI Taxonomy
• Catalogue of Life
• In Defense of Clothes Moths, Marvels of Evolution
• Tinea pellionella Archives - Entomology Today
• Itty bitty tiny little flies | Beetles In The Bush
• Studies on the Bionomics of the Case-bearing Clothes Moth, Tinea pellionella (L.)
• Observations on the ecology of the cloths moths Tineola bisselliella (Humm) and Tinea pellionella L in a bulk wool store.
• The genome sequence of the Case-bearing Clothes moth, Tinea pellionella (Linnaeus, 1758).