Comparative studies of co-occurring species using overlapping resources may help in understanding the mechanisms supporting biotic diversity in species-rich regions, such as the Mediterranean region of Europe. Three Papilionidae butterflies,Archon apollinus,Zerynthia cerisyandZerynthia polyxena, develop onAristolochiaplants and co-occur in Greek Thrace. We used mark–recapture to describe adult demography and dispersal, and searched for eggs and larvae to assess host plants and microhabitat preferences. Adult flight timing followed a sequence from earliestA. apollinus, throughZ. polyxenato lateZ. cerisy; this was more prominent in 2010 (warm early spring) than in 2011 (cold delayed spring). Population densities were highest forA. apollinusand lowest forZ. cerisy, whereas dispersal ability followed a reverse pattern. Adults of all three species crossed distances > 3 km and used all habitat types present. FourAristolochiahost plants were used at the study locality: smallAristolochiapallida, intermediateAristolochiarotundaandAristolochiahirta,and bulky, late-sproutingAristolochiaclematitis. BothA. apollinusandZ. polyxenaused all fourAristolochiaspecies, the former preferringAristolochiarotundaandAristolochiahirta, the latterAristolochiarotundaandAristolochiapallida. Zerynthia cerisydid not use the early-growingAristolochiapallidawhile frequently using the late-growingAristolochiaclematitis. Further parameters affecting oviposition were biotope and canopy closure: earlyA. apollinustolerated shady sites but lateZ. cerisyavoided them. The simultaneous use of several host plants differing in phenology and habitat requirements, combined with rather high dispersal ability, arguably buffers the butterflies’ population dynamics against yearly variation in weather, while allowing efficient occupation of the diverse Mediterranean landscapes. The regional habitat diversity, created during millennia of human activity, is currently threatened by land abandonment, which may diminish the resource base for the studied butterflies. [ABSTRACT FROM PUBLISHER]