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ISSN 1312-9082 Senior editor: Josef Settele The main aim of the series is to attract the attention of both academics and society to model studies in invertebrate ecology and conservation. It is also intended to include in-depth studies supported by detailed data, which nowadays are rarely published as complete works because of their volume, but which are often much more sustainable than many high impact journal papers. Volume 2 Ecological Traits and Genetic Variation in Amazonian Populations of the Neotropical Millipede Poratia obliterata (Kraus, 1960) (Diplopoda: Pyrgodesmidae) (Brazil) by Natalie Bergholz he periodic flood pulse of the Amazon River has been the main controlling factor in the riverine ecosystem for at least two million years. Numerous adaptations, in some cases along with speciation, have evolved in the resident terrestrial invertebrates. Having probably originated from the Andes, the small millipede Poratia obliterata (Kraus, 1960) is currently known as bisexual from all over Amazonia and as parthenogenetic from some European hothouses. Seasonal vertical migration to tree trunks, aggregation and a univoltine life cycle appear to be adaptive traits of individuals living in Central Amazonian inundation forests. Such developed survival strategies can either reflect ecological plasticity or implicate ecological speciation, i.e. ‘biotope-specific races’ or ecotypes. To assess the causal mode of adaptation, ecological studies were combined with genetic analyses. The allozyme data did not support biotope-specific genetic adaptations of P. obliterata in Central Amazonia. Comparing the distribution, biotope range, population subdivision and genetic diversity of different millipedes, the species P. obliterata appears to feature a generalist strategy. The results show low divergence between Amazonian populations of this diverse and widespread species, which seems to cope well with various