Belonging to the order hemiptera or true bugs, bed bugs are household vampires that feast on blood. They undergo a slow metamorphosis through a 5-stage life cycle that begins as an egg hatching into a nymph to end as a mature breeding adult with a nasty bite. 

In this guide, we’ll walk you through what a bed bug is, how to spot them, and their life cycle. 

The common bed bugs are interested in humans and don’t go for animals with fur. They can cover a lot of distance and travel about in personal belongings such as purses, luggage or gym bags. Bed bugs hate heat, so they won’t travel directly on your body, so protecting your belongings is the best way to prevent infestation.

Have you seen apple seeds? Adult bed bugs look quite similar. Depending on their age, they are between 4.5mm and 7mm long and go from white when first hatched to a deep mahogany brown. A closer inspection reveals six legs, an oval-shaped abdomen and two short antennae. 

Being an insect their anatomy is divided into three parts, head, thorax and abdomen. 

Head: Bed bugs have a tiny head and an eye on each side for 180 degree vision. For a nose they have a sharp ‘beak’, the clypeus, used to pierce skin. You may not notice it’s long proboscis since bed bugs keep it tucked under their bodies unless they are feeding. There are also two antennae. 

Thorax: The midsection of a bed bug is called the thorax. Compared to other insect thoaxes, it’s quite tiny. Nearby there are rudimentary ‘wing casings’. There are no wings. 

Abdomen: The abdomen of a bedbug is its most noticeable body part. In fact, it’s usually twice as wide as the thorax and around four times as long. From above, it looks quite rounded, but from the side, it looks flat.Unlike many other similar-looking bugs, their bodies look quite segmented when you view them from above, and that separates them from carpet beetles and spider beetles. Their oval-shaped bodies also help identify them. 

They are wingless, which means they just cannot fly. Many people say that bed bugs can fly because they have wing pads. That’s not true because they do have the vestiges of wings but they are not developed enough to help them fly. 

So, how do they move? 

Well, they crawl, and more interestingly, they are capable of covering up to 4 feet in a minute. 

It may not seem far, but it’s usually enough for them to find a hideout when you try to kill them.

In their lifetime, bed bugs go through three stages including molting twice as an adult. 

Egg: Eggs are tiny and pearl white in color. They are laid in dark spots around your home. They take about 6 to 9 days to hatch. 

Nymph: During the second stage, nymphs or juvenile bed bugs hatch and are around 1.4mm long although some can be up to 4mm. Each nymph passes through five stages, known as instars to become an adult, and it takes about 5-8 days to complete each instar. Nymphs look like adults but they cannot breed. 

Adult: Once hatched, a bedbug takes around 35-40 days to mature. They can be as large as 7mm and at this stage are capable of reproduction. Under ideal circumstances, adults can live up to 10 months, but their lifespan is usually between 3 and 10 months. 

When you talk about getting rid of a bed bug infestation, it’s important to try methods that clear the adults and eggs, as well as all the nymphs. 

Being white, nymphs are harder to spot but they only stay white until they take their first feed. Nymphs have a red lump in their abdomen where they store their blood meal as they slowly digest it. Once it’s completely digested they molt and shed their exoskeleton so they can grow larger. 

As they continue to digest and grow they turn brown. The color change shows they have absorbed the nutrients in the blood. In total, the nymph passes through five sub-stages or instars and with the completion of each, they get browner. Once an adult, they don’t change color again. 

Nymphs molt during instars and will molt five times altogether before they are mature adults. Between each molt, they need a blood meal to survive. Even though nymphs are small and too young to breed, they are still looking for a meal from the instant they hatch.