Dralarva is a rare pure Bug-type. The most resilient Dralarva will evolve into Imitisalis (also pure Bug) whose chrysalis imitates the shape of a dragon. It bides its time until it evolves into Arthrausta which is based on the concept of Pyrausta, a insect-like dragon. Naturally it is Bug/Dragon.
However more aggressive Dralarva are likely infected. Something sinister happens after it pupates into Parasilis (Bug/Fire). The parasite has melted the previous creature and flies the now empty pupa. It then evolves into Vespinferno (also Bug/Fire) which is based on parasitoid wasps that lay their eggs inside caterpillars.
Both are pseudo-legendaries
by lebibleimaginaredami