Vicariance and ecological dispersal in Papilio subgenus Achillides (Papilionidae) and some other butterflies of Asia and the Southwest Pacific

Author(s): Grehan, John R | Abstract: Biogeographic patterns are reviewed for four widespread Southeast Asia butterfly groups in the superfamily Papilionoidea: Papilio subgenus Achillides Hubner, 1819 (Papilionidae), the birdwing butterflies (Papilionidae tribe Troidini), Genus Polyura Billberg, 1820 (Nymphalidae), and Genus Vanessa Fabricius, 1807 (Nymphalidae). The patterns of allopatry and sympatry are shown to be consistent with the vicariance of widespread ancestors with distributions including parts of Asia and Australasia, followed by secondary range expansion. Aspects of the distributions that are correlated with tectonic structures provide evidence of the age and origin of these butterflies in South-east Asia and Australasia. The transpacific affinities of the Troidini are consistent with a Pacific ancestry linked with former Cretaceous landscapes. The multi-island ranges of many of the butterfly species in Southeast Asia represent examples of metapopulation structure in which groups survive and persist in a region over long periods of time, even where individual islands are ephemeral.