Drifting Spiders or Continents?: Vicariance Biogeography of the Spider Subfamily Laroniinae (Araneae: Gnaphosidae)

<it>Platnick, N. I. (Department of Entomology, The American Museum of Natural History, New York, New York 10024) 1976. Drifting spiders or continents?: vicariance biogeography of the spider subfamily Laroniinae (Araneae: Gnaphosidae). Syst. Zool. 25:101–109</it>.—It is suggested that the role of ballooning as a mechanism of intercontinental dispersal in spiders has been greatly overemphasized, at least for medium-sized and large ground-dwelling species; that most intercontinental distribution patterns in spiders are the result of vicariance in response to changing geography rather than chance dispersal; and that hypotheses based on vicariance, unlike those involving ballooning, are testable (by correlation with known geological events) and have predictive value. An analysis of the vicariance patterns of the genera of the spider subfamily Laroniinae and the species of the genus <it>Callilepis</it> is presented, and is tested by correlation with the geological events involved in the breakup of Pangaea according to current theories of continental drift; this analysis was successfully used to predict the occurrence of <it>Eilica</it> in India before any Asian specimens of that genus were known.