As we have already known before, cockroach is one kind of insects which has brown flat-rounded body. The adults have size of approximately 5 cm. Roach has one head that is hided under the protonum and also wings under the exoskeleton.
As many other animals, cockroach has a life cycle. The reproduction relies on eggs. As other insects, cockroaches has a metamorphosis phase, but it is different from butterfly or other insects which has cocoon phase.
How were the cockroach life cycle?
First phase: Eggs
Three days after mating, female cockroach produces egg cases named ootheca which contains eeggs. In this cockroach life cycle step, each female usually produces between 6 to 14 ootheca in one lifetime. Each ootecha contains approximately 16 to 37 eggs. The ootecha is carried on the tip of the female abdomen for a couple of days, and after that deposits it in a hidden location like cracks, crevices, or debris on the floor shortly before the eggs are ready to hatch.
The eggs themselves have hard and brown shell to protect the embryos and covered with the female’s saliva. A German cockroach can produce 300,000 more roaches in one year, while an American cockroach can produce 800 new roaches per year.
No cocoon, but growing
After two weeks to two months, the eggs hatch. The hatched roaches are named as nymphs. They are white, and turn into brown shortly after birth. Their exoskeletons also harden and they are still wingless. Not like usual metamorphosis, the nymphs grow without cocoon phase.
They shed their skin (molting) multiple times. The German cockroach molts 6 to 7 times in 3 months before developing into an adult. American cockroach needs more than a year to become adult. This period also depends on the environment, diet, and other conditions. Better the environment, faster the growth, and vice versa.
Imago is the adult form of insects which have passed the eggs and nymphs phases. The adult cockroach is also called as imago. In this cockroach life cycle. they have already had brown and hard exoskeleton. They also have wings, both male and female. The adults are vary in size according to the species. American is the biggest, about an inch long.
German has about a half-inch long. After the roaches reach the adult phase, they are ready to reproduce and hatch eggs again. They only need a relatively short lengths of time to repeat the phases. That is why a cockroach infestation prevention must take the fast way to get rid of them.
Watch explanation about roach life cycle through this video :