Webbing clothes moth

Hodges #

0426

IUCN Red List

not listed

NatureServe

NNA - Not applicable
SNA - Not applicable

Minnesota

not listed

Webbing clothes moth is a small exotic moth. It is native to the Western Palearctic, including Europe, and it has been accidentally introduced elsewhere. It is now cosmopolitan, occurring on every continent except Antarctica. The species is profoundly synanthropic, thriving specifically in human-made environments. Its spread has been facilitated by humans traveling to distant countries, unwittingly transporting the moth, larvae, or eggs in their belongings. It is especially common in large metropolitan areas around major cities, and it is rarely found in rural areas.

Webbing clothes moth is considered a pest, but its numbers are declining, at least in the UK, probably due to the increased use of synthetic fibers. Since it is synanthropic, it can occur anywhere where humans aggregate, store goods, or leave organic debris. This includes not only residential houses, but also textile warehouses and factories, antique shops and auction houses, museums, taxidermy studios, storage units, theaters, and costume shops. They are found in shipping containers and cargo holds, which were historically the primary conduits of their spread. They are a pest in libraries housing older books with casein-based glues and leather bindings. They may occasionally occupy the nests of birds or rodents, but these occurrences are almost exclusively limited to nests found in or on human dwellings.

The larvae feed on wool rugs and blankets, cashmere sweaters, horse-hair stuffed furniture, fur coats, and other materials made of animal-based fibers; on hair, feathers, and dead insects, including insect collections; and on bran, semolina and fine-ground flours, and biscuits. They also feed on dried, processed, or soiled sources of milk protein (casein). This is often in the form of milk spilled on a wool rug or furniture that hasn’t been perfectly cleaned. They spin tunnels or sheets of silken webbing to cover themselves as they feed.

Adults are active year-round since they inhabit primarily climate-controlled environments. They do not feed. Unlike many other moth species, they are averse to light; instead of fluttering around lamps, they prefer to remain in dark, undisturbed areas such as closets, baseboards, or the undersides of heavy furniture. They do not feed and are short-lived. At about room temperature (65° F [18° C], presumably in a controlled laboratory environment), females live up to 21 days and males live up to 37 days.

Adults are ¼″ (6 to 7 mm) in length and have a ½″ to ⅝″ (12 to 16 mm) wingspan. The forewing length is ⅛″ to ⅜″ (4 to 9 mm). The body is long and narrow.

The head is small and rusty yellow, and it is often tinged brown. There is a tuft of reddish-gold hairs on the top of the head. The compound eyes are dark and prominent; those of the male are noticeably larger than those of the female. The mouthparts are reduced and the maxillary palps, if present, are very short. The labial palps are long and curved upward in front of the face.

The thorax and abdomen are pale yellowish brown.

The forewings are long, lance-shaped, and golden buff with a distinctive satiny luster. They are held tent-like over the abdomen when at rest. There is no black spot in the median area, but the discal cell sometimes has a faint brownish dot. The fringe is long and pale. The hindwings are grayish yellow.

The legs are yellowish brown. On each leg, the fourth segment (tibia) has a long spur at the tip.

The larvae are white with a brown head capsule.

Size

Total length: ¼″ (6 to 7 mm)

Forewing length: ⅛″ to ⅜″ (4 to 9 mm)

Wingspan: ½″ to ⅝″ (12 to 16 mm)

Similar Species

Dark-collared tinea (Tinea apicimaculella) thorax is dark brown or black. On the forewing there is a narrow black streak through the central area and a black dot in the median area.

Anywhere humans aggregate, store goods, or leave organic debris.

Season

Year-round

Behavior

The larvae spin tunnels or sheets of silken webbing to cover themselves as they feed.

Adults are averse to light and prefer to remain in dark, undisturbed areas.

Life Cycle

If sufficient food is available, the larvae can mature in as little as 35 days. If not, they may take up to two years to mature.

Adults do not feed and are short-lived.

Larva Food/Hosts

Materials made of animal-based fibers, hair, feathers, dead insects, bran, flour, biscuits, and dried or processed, milk protein (casein).

Adult Food

Adults do not feed.