Hypermetamorphosis, or heteromorphosis,[1] is a term used mainly in entomology; it refers to a class of variants of holometabolism, that is to say, complete insect metamorphosis. Hypermetamorphosis is exceptional in that some instars, usually larval instars, are functionally and visibly distinct from the rest. The differences between such instars usually reflect transient stages in the life cycle; for instance, one instar might be mobile while it searches for its food supply, while the following instar immediately sheds its locomotory organs and settles down to feed until it is fully grown and ready to change into the reproductive stage, which in turn, does not have the same nutritional requirements as the larvae.