Madagascar Hissing Cockroach, Gromphadorhina portentosa

Madagascar Hissing Cockroach

This is a large wingless cockroach from Madagascar (an island off the east coast of Africa), the only place in the world it is found. Living on the forest floor, amongst the dry litter, it feeds on decaying plant matter and fallen fruit, and also smaller insects and animal carcasses. They are therefore part of the "clean-up crew" of the forest.

Because they cannot fly, they are primarily nocturnal to avoid predation. When disturbed, they can produce a sudden loud hissing noise, produced by forcibly expelling air through small holes on either side of their abdomen.

Females are often larger, and males possess large "horns" or bumps behind the head. Males are more aggressive than females, defending their territory and any females in it from intruding males. The horns are used to ram into each other when fighting – larger males usually wins, and winners hiss more than losers.

After mating, a female carries the fertilized egg sack inside her abdomen and releases the nymphs after hatching, which makes it appear as if they're giving birth to live young - a rare behavior among insects. One female can produce 15 to 40 nymphs, which undergo 6 molts before reaching maturity in 7 months. They can live 3 – 5 years.

 

 

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