A Preliminary Appraisal of the Braconid (Hymenoptera) Fauna of the Krakatau Islands, Indonesia, in 1984-1986, with Comments on the Colonizing Abilities of Parasitoid Modes

One hundred and two species of Braconidae, comprising 15 subfamilies, were collected on the four Krakatau Islands in Sunda Strait, Indonesia, in general surveys made in 1984, 1985 and 1986, about a century after the devastating 1883 eruption. The braconid fauna of Anak Krakatau, which emerged from the submarine caldera of Krakatau in 1930 and suffered a self-devastating eruption in 1952, was distinct from that of the three older islands, whose biota dates from the 1883 eruption. Anak Krakatau's braconid fauna, evidently like that of the older islands between 1908 and 1933, was heavily biased towards koinobiont endoparasitoids of Lepidoptera, mostly of the braconid subfamilies Cheloninae, Microgastrinae and Rogadinae. In contrast, not one koinobiont endoparasitoid of the cyclorrhaphous Diptera, Coleoptera or Hemiptera was collected on Anak Krakatau, although 31 such species were collected on the three older islands. The differences between parasitoid modes that relate to colonizing ability are briefly considered and discussed.