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The millipede fauna of Eurasia (with North Africa + Macaronesia, but without New Guinea) includes over 4,000 described species from about 750 genera, 87 families and all 16 orders. The basic patterns of distribution of Recent millipedes in Eurasia show the group's propensity to dwelling in the most ancient forest biomes, i.e. subtropical, broadleaved, and tropical forests. However, toward the north (the taiga and, especially, the tundra belts) and centre (the steppe and, especially, the desert belts), a number of marked trends are observable, parallelling the increase in climatic rigor, viz., a gradually decreasing general taxonomic and life-form diversity, reduced body size, mesophily, proportions both of primitive taxa and certain morphotypes, etc. In contrast, some other parameters, such as the geographic range, shares of juloid morphotype representatives, of phylogenetically advanced, xerophilic, parthenogenetic and periodomorphotic forms, tend to grow. The trophecological integrity of Diplopoda as a primarily forest floor-dwelling group coupled with the present-day distribution patterns, former zoogeographical connections and Eurasia's well-documented palaeogeography and palaeobotany provide a sound causal basis for reconstructing millipede faunogeneses. Such a reconstruction is attempted as well as a crude regionalization of the millipede fauna of Eurasia, in which four main faunal nuclei are distinguished. Whereas the evolution of the Oriental nucleus since the early Cenozoic seems to have been relatively smooth and stable, that of the Holarctic nucleus has been highly dramatic to catastrophic. The latter's oldest, still perceivable derivatives, viz., the ancient Mediterranean and the Japanese Manchurian nuclei, are now fully isolated and are mainly composed of broadleaved forest refugia of the Turgai type, with their accompanying millipede faunas likewise restricted to several montane areas at the southern periphery of the Palaearctic. Finally, due to Europe's particular history during the Plio-Pleistocene, a fully migratory European millipede nucleus has been developed, which is expressed at the species level and declines gradually toward the Ural Mountains together with the entire belt of broadleaved forests.