Centipede diversity
The remarkably low z-value (<0.18) for all centipedes, even lower than reported for vertebrates (Triantis et al. 2008), is probably explained by low degrees of island isolation fitting with the paleogeography of the Aegean, where most of the islands were recently connected either with continental Greece or the Anatolian peninsula. Although Crete became permanently isolated approximately 9 Mya from Anatolia to the east and 5.5 Mya from mainland Greece from the west, the majority of the islands were isolated less than 21 Kya (Perissoratis and Conispoliatis 2003). The absence of endemic centipedes on land-bridge islands confirms our H2, namely that endemism is demoted on land-bridge islands. For native centipedes, higher z-values and R2 values on true islands compared to land-bridge islands support higher levels of native centipede diversity. This counterintuitive trend is most likely a reflection of suitable cryptozoic habitat types on true islands, the change of occurring on these islands increases with island size. All centipedes are predatory soil animals with distinguished dispersal abilities that show ecological preferences to microhabitats such as leaf litter in the upper soil layer, into cavities in the deeper soil layers as well as under stones and barks (Voigtländer 2011). Because of their cryptozoic life-style most centipede species seem to be more insensitive than most angiosperms to geographical changes caused by sea-level rise in the Aegean archipelago. This could justify the less significant role of paleogeography (LGM and median) in the diversity patterns of the centipedes in the Aegean archipelago. One of the most exceptional features of certain centipede species, particularly geophilomorphs, is that they reside on the sea shore between tidemarks (e.g. Pachymerium ferrugineum , Tuoba poseidonis , see Lewis 1981). Thus, periods of high rates of sea-level rise such as following the LGM might have caused fast extinctions in these taxa, leading faster to a new equilibrium. Centipede species richness is therefore mainly determined by present-day geography (Table 1), with area and distance from mainland being the most significant variables for total species richness, meaning that centipedes tend to be faunistically relaxed. However, Kastelorizo, Ro and Stroggyli are supersaturated with centipedes as a result of their connection to Turkey during the LGM. Kastelorizo for example is about 800 times smaller than Crete but hosts 19 species of centipedes – roughly half the richness found in Crete.