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Difference between American Roaches and German Roaches

Difference between American Roaches and German Roaches

Cockroaches have been around since prehistoric times, and have been a pest to mankind ever since man gave up his nomadic lifestyle and opted for a settled, sedentary life. Out of the 4600 species of roaches, only 30 species are encountered by humans in daily life. The most prevalent of these 30, are the American cockroach and the German cockroach. Find out what the key differences of these two species are, in this article.
Komal B. Patil
Death by Thirst
Cockroaches can survive for a month without any food, but can only survive for a week without water.

Cockroaches are one of the most adaptable creatures on the planet. They boast of abilities such as being able to withstand very low temperatures, running as fast as 3 miles/hour, and being able to hold their breath under water, for as long as 40 minutes at a time. These capabilities along with a few other qualities have rendered this insect as one of the most prevalent and cumbersome pests to mankind. They are often seen near human settlements, due to the easy availability of food. While their consumption of our food materials is itself a problem, they also leave behind disease causing germs and allergens, wherever they go, leading to major health and safety concerns.
Cockroaches are arthropod insects that can survive almost anywhere. This is due to the fact that they can feed on almost everything, ranging from paper to soap. Also, their compact size and fast speed allow them to hide and live in tiny cracks and crevices. The most widely seen roach infestations are of American and German roaches. These two hardy species can be seen scuttling across many a kitchen counters, and the best way to be rid of their presence is by identifying the exact species and implementing appropriate extermination tools.
Comparison Chart
American Roach German Roach
Scientific Classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Blattodea
Family: Blattidae
Genus: Periplaneta
Species: P. americana
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Blattodea
Family: Blattellidae
Genus: Blattella
Species: B. germanica
Physical Description
They are amber colored, with a reddish-brown hue. They show the presence of a yellow plate on the back on their head that bears a mark shaped as a horizontal eight, and can grow up to 3 inches in length. They are brownish in color, and show the presence of two vertical dark stripes on the back of their head. They can grow up to a length of 0.5 - 1 inch.

They consume leaves, wood fragments, fungi, algae, smaller insects, and crumbs and scraps of human food.

They feed on almost anything, including things like toothpaste, paper, soap, leather, etc. They also scavenge on any human food that is left untended.
They prefer warm and damp outdoor habitats, with the presence of mulch. They are often found in sewers and drain pipes. They prefer a warm and slightly damp indoor environment, and are often observed in kitchens and bathrooms.

Females lay eggs within protective shells, called ootheca, in a warm and damp environment. These shells resemble capsules, and carry about 16-20 eggs at a time. In a single laying, a female will lay 9-10 of these oothecae. Once the eggs mature, the new off-springs, called nymphs, hatch from the shell. These nymphs undergo several instar stages before fully maturing into an adult. Every instar stage is marked by the occurrence of ecdysis (molting). This process may take 5-7 months to complete. In a year, a female produces up to 150 off-springs. They are the fastest reproducing species. The female produces 3-6 oothecae, with each shell containing around 35 eggs. The eggs mature in the shells, inside the mothers body till 1-2 days before hatching. On expulsion of the ootheca from the females abdomen, the nymphs hatch within 48 hours. Once hatched, they too undergo ecdysis and instar stages. It takes almost 3 months for the nymphs to mature into adults.

Their droppings are often confused with those of mice, but mice droppings show the presence of hair. The droppings of these roaches are small and blunt-ended. They also show the presence of ridges on the sides. Their droppings are small, dark, and appear like pepper flakes. They also leave fecal stains, in the form of smears or spots, on any surface that comes in contact with it.

Rising populations, lead to the production of a musty odor. They also produce a musty smell.

Ability to Fly
They can fly with ease.

They can barely fly, and are seen gliding, at best.
1 to 2 years. 0.5 to 1 year.
To prevent a cockroach infestation in one's home, it is advisable to keep all kitchen surfaces clean. The containers used to store food products must be clean and tightly sealed. All cracks and holes in the walls should be promptly sealed. Also, the garbage should be regularly and appropriately disposed off. In case these methods fail, and an infestation still occurs, one must consult and hire a professional pest exterminator to help get rid of these cockroaches.