Endopterygota

http://tolweb.org/Endopterygota/8243

ndopterygotes are those insects with distinctive larval, pupal, and adult stages. Their name (endo = within, pterygos = wing) refers to the fact that in later immature stages the wing buds are not evident externally, but instead the future wing tissues are entirely internalized; they make their first external appearance in the penultimate (pupal) stage. In contrast, other winged insects (for example, bugs) have external wing buds in instars before the penultimate.

Another name for this group is Holometabola, referring to the "complete metamorphosis" of the species; that is, the dramatic changes between larval, pupal, and adult stages.

Four of the five largest orders of insects belong to this group (Coleoptera, Hymenoptera, Lepidoptera, and Diptera).





http://entomology.ucr.edu/ebeling/ebeling4.html