The present study is a continuation of previous acarological investigations of tropical rainforests in the course of the International Biological UNESCO Program. In total, 28 new species from Chile, Paraguay, Brazil, Venezuela, Ecuador and Cuba are described and documented. Distribution and taxonomy of studied groups are explained. Keys are provided for known and new species, in total for 106 species. Based on an autapomorphy of the sperm, Ribbon sperm, the Eugamasides and Eviphidides are combined and a new taxon is erect naming Ribbondides n. subcohors. The following 12 groups are investigated: Evimirus Karg, 1963; Parholaspis Berlese, 1918; Africoseius Krantz, 1962; Afrogamasellus Loots & Ryke, 1968 – subgen. Foliogamasellus Karg, 1977; Poropodalius Karg, 2000; Dendrolaelaspis Lindquist, 1975; Rykellus Lee, 1970; Neogamasellevans Loots & Ryke, 1967; Ologamasus Berles, 1888; Hydrogamasellus Hirschmann, 1966; Parasitus Latreille, 1795 – subgen. Bacuterus Karg, 1998; Zygoseius Berlese, 1916. The Podocinidae Berlese, 1916 are revised and 9 groups categorized. Concerning their distribution it is conspicuous that taxa regarded as endemic African groups occur in South America: Africoseius Krantz, 1962, Afrogamasellus Loots & Ryke, 1968 and Rykellus Lee, 1970. Dominant are the Rhodacaroidea Oudemans, 1903. Several subgroups of this group are limited to the Neotropic where they occupy ecological niches which are held by other predatory mite groups, especially by the Parasitidae Oudemans, 1901, in the Holarctic. However, in high altitudes of 2900 to 4200 m above sea level (a.s.l.), Parasitidae were detected. Some groups are distributed worldwide: Pachylaelaps Berlese, 1886, Hypoaspis Canestrini, 1885, Ameroseius Berlese, 1904, Lasioseius Berlese, 1916 and Multidentorhodacarus Shcherbak, 1980. The distribution is analysed by means of the Historical Zoogeographic Method, revealing connections to past geological events. It leads to the following conclusion: Ancestral groups that are distributed worldwide (Hypoaspis, Pachylaelaps, Ameroseius, Lasioseius, Multidentorhodacarus) already existed in the Permian and the Triassic before Pangaea started splitting into today´s continents. Specialized forms with particular pattern of distribution developed at the end of the Jurassic (Africoseius, Rykellus, Afrogamasellus) and during the Cretaceous (Neogamasellevans, Ologamasus, Hydrogamasellus and Parasitus) (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
