Beetle?
it's hard shell
That is very hard to tell. You will have to study their genitals (really!) with a microscope. In general males are larger than females.
A beetle is a small round bug with a hard shell. There are several beetles that are black spotted. One example of a black spotted beetle is a lady bug.
it's made of a certain amont of bug shells and hard plastic
No some bugs have exoskeletons thoughNo.Insects rely on their hard shell to provide structure and leverage.
no an exampl of an exoskeleton is a bug because the have no bones but they have a hard outer shell
In a bed?
bed bug
There are several kinds of bugs that are big and brown with a hard shell. However, you are probably thinking of the American cockroach, which is one of the most well known pests.
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Certain types of beetles have a black back with white spots. The eyed click beetle is an example of this type of bug.