Zoogeography of the Amiseginae and a Remarkable New Chrysidid Wasp From Chile (Hymenoptera)

Members of the chrysidid subfamily Amiseginae are small, ant- like wasps, with slender mandibles and a long needle-like ovipositor. Although hosts are known for only a few amisegine species, the morphology of the female mandibles, used to open the host egg, and the structure of the ovipositor are remarkably consistent throughout the subfamily, suggesting that all species probably parasitize walk- ing stick eggs. Amisegines occur in most zoogeographic regions. In the Western Hemisphere they are found east of the 100th meridian in North America and as far south as northern Argentina. No amisegines were previously known from Chile. In the Eastern Hemisphere amisegines are not found north of Zimbabwe in Africa, nor in the palearctic except in Japan. This subfamily is widespread in the Oriental and Australian Regions. As with the rest of the Chrysididae (Kimsey and Bohart, 1990), the Amiseginae appear to have evolved in the Northern Hemi- sphere. The oldest fossils are in Eocene amber from the northern USSR (Krombein 1986, Evans 1973), indicating that there were species in the Palearctic Region at one time. Extinction of this group in the continental palearctic may have been due to the Pleis- tocene glaciations. Cladistic analysis of the amisegine genera (Kim- sey and Bohart, 1990) indicates 3 basic lineages, which clearly show continental relationships. The American genera, Amisega, AdeZphe, Anadelphe Duckeia and Nesogyne, are far more closely related to each other than to the Afrotropical or Indoaustralian ones, except