Which of the following is not a characteristic of insects within class Insecta?

Insects belonging to class Insecta are characterized by having a distinct body structure that typically includes an exoskeleton, which is a hard outer covering that provides protection and support. They also possess three main body divisions: the head, thorax, and abdomen. Additionally, insects are defined by having six legs, which are an essential feature distinguishing them from other arthropods, such as arachnids.

The identification of eight legs as a characteristic of insects is inaccurate since insects have only six legs. This feature helps to differentiate insects from arachnids like spiders, which do have eight legs. Therefore, the option identifying eight legs does not align with the defining characteristics of insects within the class Insecta, making it the incorrect choice in this context.