Giant Water Bug Stock Photos

Wild Giant Water Bug

Giant Water Bug is a fascinating species, but it is declining across the country, and we have fewer opportunities to see it up close. Let’s take a look at Giant Water Bug photos from different angles and enlarge them to see the details.

Giant Water Bug is found all over the world, but the one in this article is from Japan, scientifically named Kirkaldyia deyrolli. Kirkaldyia deyrolli is a largest aquatic insect in Japan, with a body length of nearly 7 cm.

Giant Water Bug has been a protected species in Japan since 2020, but hobby keeping is not regulated.

Photo Credit

Photos in this article can be used in various media with credit to @gengo6com. If the article is to be published on the Internet, please link to https://gengo6.com/. For TV media, please let me know in advance which program will be aired and when.

Photos of adult Giant Water Bug

Giant Water Bugs waiting for food
Giant Water Bugs waiting for food
Giant Water Bug Group
Giant Water Bug Group
Giant Water Bugs attacking dojo
Giant Water Bugs attacking dojo
Giant Water Bug eating fish(Loach)
Giant Water Bug eating fish (Loach)

In the photo below, the Giant Water Bug has a white cottony water mold on its proboscis. This is common in captivity, but does not seem to affect them to the point of death.

Giant Water Bug Head
Giant Water Bug Head
Giant Water Bug's forefoot
Giant Water Bug’s forefoot

Most of the world’s Giant Water Bugs belong to Lethocerus. Japanese Giant Water Bug used to be classified as Lethocerus, but due to its large forelegs and long claws, it became independent as Kirkaldyia deyrolli.

Giant Water Bug Claws
Giant Water Bug Claws

Photos of mating and egg laying of Giant Water Bug

The Giant Water Bug is an ambush species and usually does not move much, but during the breeding season, it actively moves to find a mate.

Males of the Giant Water Bug call for females by pumping the surface of the water, leading to mating.

Giant Water Bug mating
Giant Water Bug mating
Giant Water Bug mating
Giant Water Bug mating
Giant Water Bug laying eggs
Giant Water Bug laying eggs

Mating of Giant Water Bug is carried out intermittently during spawning. Males mate many times, getting off and Mating in the Giant Water Bug is intermittent during spawning. The male mates repeatedly while climbing down and up the pole.

A pair of Giant Water Bug laying eggs.
A pair of Giant Water Bug laying eggs.

Giant Water Bug’s genitalia.I don’t know what’s going on.

Giant Water Bug mating
Giant Water Bug mating

Giant Water Bug lays its eggs in bubbles, which disappear some time after spawning. There seems to be another object that attaches the egg mass to the pile.

Egg-laying of Giant Water Bug
Egg-laying of Giant Water Bug

Giant Water Bug forms egg masses and lays its eggs from the top down.

Egg-laying of Giant Water Bug
Egg-laying of Giant Water Bug

In the photo below, one of the eggs is darker than the rest, and it looks like it’s sterile.Not all Giant Water Bug eggs hatch.Sometimes the hatch rate is as low as 50-70%.

Egg-laying of Giant Water Bug
Egg-laying of Giant Water Bug
a male whose Giant Water Bug female leaves and enters the protection of egg masses
a male whose Giant Water Bug female leaves and enters the protection of egg masses

Egg mass destruction by a female Giant Water Bug

The destruction of egg masses by female Giant Water Bugs is a frequent occurrence in captivity. Unless the egg masses (and the males protecting them) are isolated, it is safe to say that they will be destroyed first.

a Giant Water Bug female that attacks egg masses and nourishes them
a Giant Water Bug female that attacks egg masses and nourishes them

The female attacking the egg mass and the males to protect fought and knocked down the struts. After that, the female In the photo below, a female turtle attacking an egg mass and a male protecting it fought and knocked over a post.

The female then sucks the eggs for sustenance, and the male also resists at first, but is often driven away by the larger size of the female.

a Giant Water Bug female that destroys egg masses
a Giant Water Bug female that destroys egg masses

Extra. A chaotic photo of a pair of Giant Water Bug laying eggs and another individual eating a loach.

Giant Water Bug sometimes feed on the water to prevent others from taking their food if the surroundings are noisy.During spawning, the male climbs up and down and makes a lot of noise, so I think this is what happened.

Spawning Giant Water Bug and eating Giant Water Bug
Spawning Giant Water Bug and eating Giant Water Bug

Photos of Giant Water Bug egg masses and their hatching.

It is well known that male Giant Water Bugs are protective of their egg masses, but they don’t stick around all the time. They may be found at the base of a support pole, and climb up when stimulated.

Even though they are aquatic insects, Giant Water Bug are not completely adapted to living in water, and lay their eggs on the water. They lay their eggs on the water, and if the eggs are not watered, they will dry up and not hatch. Water supply by the male or a human is the key to development.

Egg mass of Giant Water Bug
Egg mass of Giant Water Bug

Eggs of Giant Water Bug basically expand every day. A deflated egg is a damaged one.

Egg mass of Giant Water Bug
Egg mass of Giant Water Bug

Eggs of Giant Water Bug are green immediately after spawning, and then brownish streaks appear. These gradations appear because the eggs are laid in order from the top.

Giant Water Bug egg mass immediately after spawning
Giant Water Bug egg mass immediately after spawning
Giant Water Bug that protects egg masses
Giant Water Bug male that protects egg mass
a Giant Water Bug male that protects egg mass

Giant Water Bug larvae do not always hatch in unison, although they are famous for their simultaneous hatching photos.

However, Giant Water Bug larvae do not always hatch at the same time. In captivity, they may hatch in different stages, depending on the lighting conditions. In this case, the hatching rate is often extremely low, such as less than half.

Hatching of Giant Water Bug
Hatching of Giant Water Bug
Hatching of Giant Water Bug
Hatching of Giant Water Bug
Hatched Giant Water Bug larvae
Hatched Giant Water Bug larvae

The hatched Giant Water Bug larvae fall into the water. Yellow one in the photo is just after birth. A few hours later, the striped pattern unique to the first instar larvae emerges.

a newly hatched Giant Water Bug larva
a newly hatched Giant Water Bug larva
Hatched Giant Water Bug larvae
Hatched Giant Water Bug larvae

Photos of Giant Water Bug larvae

The larvae of Giant Water Bug are characterized by a large variation in color and pattern from one stage to the next. In particular, the first instar larvae of Giant Water Bug are striped blackish-brown in color, which differs from the greenish body color of the second instar and later.

Giant Water Bug grows quickly and is capable of feeding on prey more than twice its length immediately after birth. It is also common to see multiple Giant Water Bug larvae attached to a rampaging prey.

Giant Water Bug 1 larva preying on killifish
Giant Water Bug 1 larva preying on killifish
Giant Water Bug 1 Larva
Giant Water Bug 1 Larva

The photo below shows the first instar larva of a turtle attacking a killifish. The belly is swollen.

One of the reasons why the first and second instar larvae are so prone to death is that some of them are born in groups of 50 or more, so they do not get enough food. Giant Water Bug larvae with floppy and thin abdomen are not getting enough food.

Giant Water Bug 1 larva attacking killifish
Giant Water Bug 1 larva attacking killifish
Giant Water Bug larvae with their stomachs swollen with nutrition
Giant Water Bug larvae with their stomachs swollen with nutrition
Giant Water Bug larva eating guppy
Giant Water Bug larva eating guppy
Body disparity between subfamily Lethocerinae larvae and subfamily Belostomatinae larvae
Body disparity between subfamily Lethocerinae larvae and subfamily Belostomatinae larvae
Body disparity between subfamily Lethocerinae larvae and subfamily Belostomatinae larvae
Body disparity between subfamily Lethocerinae larvae and subfamily Belostomatinae larvae

Immediately after molting, Giant Water Bug larvae glow emerald green, but after a while they return to a more subdued color.

Giant Water Bug 2-larva immediately after molting
Giant Water Bug 2-larva immediately after molting
After coloring immediately after the turtle 2 order molting
After coloring immediately after the turtle 2 order molting
Body disparity between Giant Water Bug 1 and 2
Body disparity between Giant Water Bug 1 and 2
Body disparity between Giant Water Bug 1 and 2
Body disparity between Giant Water Bug 1 and 3

Some books say that Giant Water Bug larvae are cannibalistic and should be kept individually, but young larvae can be kept in groups. They frequently overlap each other, and I have the impression that they do not actively cannibalize each other.

In the case of insufficient food, the young larvae simply die, and cannibalism tends to occur when they become about four or five years old.

Overlapping Giant Water Bug 2 larvae
Overlapping Giant Water Bug 2 larvae
Giant Water Bug 2 Larva
Giant Water Bug 2 Larva

The second instar larvae of the Giant Water Bug are gourd-shaped, but when they reach the third instar, their width increases.

Giant Water Bug 3-larva immediately after molting
Giant Water Bug 3-larva immediately after molting

Giant Water Bug larvae are larger and more numerous when they reach the third instar stage, so they fill up their rearing containers.

Population of larva of the 3-order Giant Water Bug
Population of larva of the 3-order Giant Water Bug

In the case of the Diving Beetle larva, the body segments grow longer, but in the case of the Giant Water Bug, as it grows, the upper and lower parts of the body become thicker and swell up like a water bottle before finally molting.

In the photo below, the pronotum is already cracked and the Giant Water Bug larva has begun to molt.

Larva of the turtle 4 just before molting
Larva of the turtle 4 just before molting

Key to success in the Giant Water Bug larval molt is the clean exit of the legs. The larvae that become defective due to the leg tips getting caught, for example, almost never survive.

Giant Water Bug 5 larva who is raised to pull out the leg
Giant Water Bug 5 larva who is raised to pull out the leg

Giant Water Bug has sharp claws on its front legs, but as a larva, it has two claws.

Claws of Giant Water Bug larvae
Claws of Giant Water Bug larvae

GGiant Water Bug larvae breathe by storing air in their abdominal cilia. In captivity, there are quite a few individuals that die from respiratory failure. It is also effective to use a filter to reduce the frequency of water changes.

Abdominal cilia of Giant Water Bug larvae
Abdominal cilia of Giant Water Bug larvae

Spiracles of the Giant Water Bug moves to the abdomen as a larva and to the back as an adult. Each black dot near the edge of the abdomen is a pneumatome.

Abdominal cilia of Giant Water Bug larvae
Abdominal cilia of Giant Water Bug larvae
Claws of Giant Water Bug larvae
Claws of Giant Water Bug larvae

Wings of Giant Water Bug do not increase in size with each larval stage, but suddenly and prominently protrude at the fifth stage.

Population of larva of the 5th Giant Water Bug
Population of larva of the 5th Giant Water Bug

Giant Water Bug’s diet consists of extracorporeal digestion, in which digestive juices are injected into the food to dissolve it. The mouth moves freely.

Head of a Giant Water Bug larva
Head of a Giant Water Bug larva
Giant Water Bug 5 larva
Giant Water Bug 5 larva
Giant Water Bug 5 larva
Giant Water Bug 5 larva

The 5-larva of Giant Water Bug changes reddish-brown with the approach of emergence.

Giant Water Bug 5 larva
Giant Water Bug 5 larva

The photo below is a female because it is large and wide.

Giant Water Bug larvae have a different body size when they reach the 5th instar stage, and it is possible to determine male and female.

Giant Water Bug 5 larva
Giant Water Bug 5 larva
Neoteny of Giant Water Bug
Neoteny of Giant Water Bug
Respiration of a Giant Water Bug larva
Respiration of a Giant Water Bug larva

Giant Water Bug hatching photo

It takes about 40 days after hatching for a Giant Water Bug to become an adult.I observed the Giant Water Bug 5th instar larvae hatching! It takes about 20 minutes for neoteny to be born.

The photo below shows a Giant Water Bug 5th instar larva with its back cracked and molting started.

Giant Water Bug larva whose back cracked and emergence began
Giant Water Bug larva whose back cracked and emergence began

The larva shakes its body and pulls out its upper body.

Emerged Giant Water Bug larvae
Emerged Giant Water Bug larvae

Wings grow in parallel with the molt.

a Giant Water Bug that stretches its wings while feathering
a Giant Water Bug that stretches its wings while molting
a Giant Water Bug that stretches its wings while molting
a Giant Water Bug that stretches its wings while molting

Adult Giant Water Bug breathes by storing air between its back and wings. For this purpose, its back is densely covered with fine hairs.

Giant Water Bug's Back
Giant Water Bug’s Back
Neoteny of Giant Water Bug
Neoteny of Giant Water Bug
Female neoteny of Giant Water Bug
Female neoteny of Giant Water Bug

Neoteny is pale in color for a while, but gradually becomes darker. The body remains soft for a few days.

Neoteny of Giant Water Bug
Neoteny of Giant Water Bug
Neoteny of Giant Water Bug
Neoteny of Giant Water Bug
Giant Water Bug Neo-Adult
Giant Water Bug neoteny, female on the left.

コメントはこちらから(個人を特定できる部分は削除します)

Your email address will not be published. Required fields are marked *