Do Praying Mantis Turn Brown When They Die?

Praying mantis appear in various colors, from mild colors like pink to darker shades or brown. Sometimes, external disturbances also lead to changes in body color.

Do Praying Mantis Turn Brown When They Die? Praying mantis turn brown when they die or are close to death due to physiological changes in their bodies. It starts from a few spots or hues and ends with a complete brown body. Molting, camouflage, lack of humidity, disease, infection, and lower temperature can be the reasons for this color change.

It is natural for a mantis to become brown completely because they respond to external changes by altering their behavior or physical appearance.

Why do dying praying mantis turn brown when they die?

Many physical and behavioral changes occur in the praying when it is close to the death phase, like changes in dietary habits, body color, activity rate, etc.

Commonly, the natural body color of most mantis species is green if they are healthy and living an ideal lifestyle. The brown spots begin to appear on their bodies for different reasons.

One of those reasons could be the mantis’s death as their body begins to change the green color when it reaches close to the death phase of their lifecycle.

They are about to die if their bodies turn brown, in addition to a decreased activity rate and lack of desire to eat food.

I learned about this fact when my mantis turned brown, and I took it to the entomologist. He told me that my pet would die shortly and it did not have a long time to live.

Small spots appear on their bodies a few days before death and get bigger over time. Their bodies turn brown entirely when a few hours remain to die.

So, you can estimate the time it can live after the appearance of brownish spots on their bodies. This time duration depends on their health, species, and age.

What other factors make praying mantis turn brown?

Few other things can cause the praying mantis bodies to turn brown other than death.

They show some behavioral changes to tell about the discomfort and other problems.

Lack of humidity

Changes in humidity level or moisture content in the environment affect their body color. Generally, a healthy mantis appears green when it is fully hydrated.

They need around 65% to 80% humidity level and feel dehydrated when the moisture content in the air decreases. Dehydration poses a risk of drying when their exoskeleton becomes hard.

Dried exoskeletons break quickly when they fall off a leaf or twig. In addition, their bodies turn brown in dry conditions to tell that they need water for hydration.

So, you should mist their cages with water or put a bowl of water inside to maintain an ideal humidity level. Their bodies appear green in color when they have access to water.


They can change color due to camouflaging behavior because they blend with the background environment to avoid predators.

It protects these insects as they can hide behind twigs, tree branches, or brown leaves and remain motionless.

It helps prevent the risk of being noticed by predatory organisms when they camouflage behind tree barks or twigs. The predators cannot recognize their bodies until they move away from them.

I noticed this behavior when I saw my mantis changing color to brown after seeing a frog close to its cage. It turned brown and hid behind the small twigs in its cage.


Molting is one of the prominent reasons for the change in body color from white or green to brown. It happens in young nymphs when they undergo molting during development.

However, it is not a sudden change in nymphs and occurs gradually over several days. This physical change relates to their transitioning phase from immature to mature adults.

This brownish hue appears on bodies before the molting stage and indicates it is ready to shed its old skin or exoskeleton. However, it can also occur after the completion of a molting stage.

Disease or infection

Fungal or bacterial infections can occur in praying mantis, which leads to the formation of dark spots on their bodies. These spots can be brown or black in color and disappear after treatment.

However, these insects turn completely brown after dying due to infections. Discoloration relates to diseased conditions when these mantis are sick and suffering from viral infections.

Parasitic infections also affect the immune system, leading to some physiological and behavioral changes. So, it is better to ask for vet help if your pet turns brown.

Adaptation to cold climate

They are cold-blooded insects that cannot tolerate extreme fluctuations in the external environment. They adapt to cold climates by changing their body colors from green to brown.

Moreover, the green-colored mantis absorbs more heat from the external environment to stay warm in cold climates. Darker bodies absorb more heat, so they turn brown to survive.

Are there any brown praying mantis in nature?

Some praying mantis are naturally brown when their genome contains genes for such color are present. Some other natural colors include pink, purple, yellowish, and green.

The naturally brown praying mantis have completely brown bodies or a few hues of this color on their body. Commonly, the ground-living species appear brown, unlike those living in trees.

One common example of such species is the Chinese mantis, which has brown colored spots on their greenish body.

I have a small Carolina mantis that naturally appears dusty brown. However, my friend has a European mantis that also appears in brown with hues of green color.

Moreover, the dead leaf praying mantis has a crispy brown body that resembles a dead or rotting leaf.

The decaying leaves and tree trunks protect from predators as they can easily merge with the background environment due to their color.

Are brown praying mantis harmful?

They are dangerous creatures due to their chewing mouthparts and raptorial forelegs, but they can only cause harm to their prey.

They are not considered harmful to humans due to their small bodies, as they cannot bite hard on the skin. A few mantis species are poisonous, but brown praying mantis are non-venomous.

Moreover, you can feel slight irritation on your hand while handling them without gloves, but their bites do not cause severe pain. They lack venom and cause no toxicity in humans.

My Carolina mantis lacks the potential to break the skin layer whenever I offer my hand to it. It is non-toxic and poses no severe harm to human health.

They eat non-poisonous or non-venomous insects, like flies, crickets, and mosquitoes. Accordingly, they do not have toxins in their bodies and pose no harm.

Furthermore, they will only bite if threatened or provoked by continuous interference, so avoiding picking or touching their bodies is better.

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