The Moth Life Cycle of Common Clothes and Carpet Moths

Jan 19, 2021

Despite their tiny size and often harmless appearance, carpet and clothes moths can unleash untold levels of chaos in your home. It’s not the adult winged moths themselves but their larvae that are rice-sized gods of cloth destruction. Not only will the larvae chew holes in your expensive wool clothing or antique carpets, but they can leave an unsightly mess behind too.

If you have a moth problem, you need to know their life cycle, so you can target them during the most opportune moment. Here is everything you need to know about the moth life cycle.

What are Carpet and Clothes Moths?

There are a few species of moths that prey on the keratin fibers of clothing and carpets.

Identifying Carpet and Clothes Moths is simplified by looking at their colouring and size, though they are usually classified by whatever they have infested, such as your closet. However, there is no actual difference between carpet and clothes moths. If they are chewing away on your clothes, then the antique rug is also at risk. 

The two species of moth that feed on fabrics—or rather, the keratin present in fabrics—are the webbing moth and case making/case-bearing moth. This is why case making moths and webbing moths will build colonies where keratin rich fibers are present, such as your silks, furs, and wools. Furthermore, because these fabrics can hold moisture, in which moths and their larvae can “drink” from, any food, drink, or sweat stains will make moths gravitate to clothing or carpets. 

What do Webbing Moths Look Like?

Also known as a Common Clothes Moth, the webbing moth (Tineola bisselliella) is golden around the head and has whitish wings. They are more active at night and will become less active the older they get. 

What do Case-Bearing Moths Look Like?

Case-bearing or Case Making Moths (Tinea pellionella) are seen throughout the year. They have mottled black and brown wings with a fringe at the bottom edge. 

What is the Clothes Moth Life Cycle?

Like most moths, clothes and carpet moths have a distinct life cycle. There are four stages of the moth life cycle: eggs, larvae, pupa/cocoon, and adult. Each stage represents a significant step in a moth’s lifespan. Knowing the life of a moth is important when trying to handle an infestation, too. 

1. Egg Stage of Clothes Moths

At the beginning of a moth life cycle, there is the egg. Upon choosing an appropriate nest, adult female webbing moths and case-bearing moths can lay around 40-50 eggs at a time. Sometimes, that number is as high as 100 eggs. These are not laid all at once but over a short span of days. 

It usually takes 4-10 days for moth eggs to hatch, though this depends greatly on humidity and temperature levels. 

2. Larval Stage of Clothes Moths

The next stage is where moths are most destructive. With an insatiable hunger, the newly hatched larvae swarm their food source and gnaw away, gaining nourishment that helps them grow. Imagine finding hundreds of larvae crawling all over your woolen blankets and cashmere sweaters… It’s horrifying.

And as you can imagine, they do not stop until it is time to become a cocoon. However, there is no set time for larvae to decide it’s time to transform. Sometimes, it takes only 2 months. Other times, clothes moth larvae will remain in that stage of life for 30 months—2.5 years. This is why clothing moths can be such a nuisance because they will survive through the cold months while feasting on keratin-rich fabric. 

3. Pupal Stage of Clothes Moths

When temperatures are warm enough, larvae will pupate. Not many people will notice this stage, because the pupae are usually hidden out of sight, in the darkened corners of closets or under radiators. The pupal stage will last up to 50 days, though it is usually between 8-10 days before adult Clothes or Carpet Moths emerge. 

Here’s a fun fact for you: when moths (and butterflies) are undergoing metamorphosis into their adult stage, there are special cells within their bodies that are activated. Those cells break the body down into a heap of gunk that gradually remodels itself. This process is called histolysis. The speed of histolysis is impacted by the environment, which is why moths in warmer climates tend to hatch and mature much more rapidly than those in cooler environments. 

If you suddenly notice moths fluttering about, go look for debris or remnants of their cocoons. You can usually find webbing cases, from which webbing moths get their name. 

4. Adult Stage of Clothes Moths

While adult case-bearing moths and webbing moths are harmless by themselves, their presence within your home should raise some questions. Interestingly, adult moths cannot eat or drink. Their only goal is to find mates and lay their eggs wherever there is enough food. 

Some adult moths live only for a week. Others can live for up to 10 months or up to a whole year. Female moths die after laying their fertilized eggs, while males tend to perish soon after mating. 

What do Moth Eggs Look Like?

Webbing moths and case-bearing moths both lay eggs amid the fabrics the hatchlings will devour. The eggs are very tiny and hard to spot (about 0.5mm), but they look like small white orbs laid in a line or cluster. Depending on the colour of the fabric, you may notice the eggs more easily, especially if hundreds have been laid in one spot. 

What do Moth Larvae Look Like?

Larvae look a little bit like white rice grains wriggling all around. They are only a few millimetres long upon hatching but will soon grow to about 1.0-1.5 cm long. Both webbing moth and case-bearing moth larvae have white or yellow bodies and round brown heads. They may leave behind trails of webbing as they progress towards their pupal stage. 

How Long Do Moths Live?

When you take into account the factors that affect the life cycle of moths, it might seem like they live forever.  

To recap: 

• Egg-laying takes 4-7 days. 
• Eggs hatch in 4-10 days. 
• Larvae eat for 2-3 months in favourable conditions or up to 30 months. 
• Metamorphosis in a cocoon can take between 8-10 days (sometimes up to 50 days). 
• Adults usually mate and lay their eggs within 4-6 days of hatching. 

So, when unaffected by modern technology and heating or the climate, the entire lifespan of a moth is anywhere from ½ a year to 3 years.

Why Learn About the Clothes and Carpet Moths Life Cycle?

Carpet and Clothes Moths are pests that need to be ousted from the household before they cause too much havoc. Understanding the stages of a moth life cycle is an important step in protecting your home from infestation. If you can tackle the problem during the moths’ inactive periods, you will have less to worry about in the future.