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Temporary ponds are small‐sized limnic systems that dry periodically. The length of the wet phase defines the hydroregime and determines community assembly in temporary ponds. Zooplankton species have adapted to desiccation by adopting some dormant strategies, such as the formation of resting stages. Hatching from resting stages is a source of recolonization after drought events and the composition of hatching taxa is also influenced by hydroregime. We compared metacommunity structure and composition of the dormant sub‐community (resting stages); the pioneer active sub‐community (fauna present immediately after inundation of ponds); and the cumulative active sub‐community (fauna present at the initial, middle and final phases of hydroperiod) in a set of temporary ponds with semipermanent and seasonal hydroregimes in two areas with mediterranean climate: central Chile and eastern Spain. We aimed to determine the influence of hydroregime and identify whether metacommunity patterns are consistent between regions sharing a mediterranean climate.We selected five semipermanent and five seasonal ponds in each region to sample sediments and active zooplankton sub‐communities. By combining hatching experiments from the sediments with direct counts of active zooplankton from the field samples, we gathered data on both dormant and active sub‐communities to build unweighted bipartite networks of species occurrences in each pond. The obtained networks were analysed to determine seasonal trends in structural features of the metacommunities (diversity, nestedness and modularity) and their relation to hydroregime (semipermanent and seasonal) and geographical location (Chile and Spain).We observed consistent differences in community structure when comparing sub‐communities at different successional stages (dormant, pioneer active and cumulative active) and with different hydroregimes (semipermanent vs. seasonal). Both α‐ and γ‐diversity showed a consistent trend, being highest in cumulative active sub‐communities and lowest in dormant ones, and were consistently higher in seasonal ponds, regardless of the region. In addition, β‐diversity was higher in the pioneer active sub‐community in both regions, with no significant differences between hydroregimes. The species composition of cumulative active sub‐communities were less heterogeneous than that of the pioneer and dormant ones. No consistent patterns were found in modularity and nestedness values across sub‐communities and hydroregimes.In agreement with our hypotheses, we observed a gradual accumulation of taxa as well as community homogenization over time in both regions. Contrary to our expectations, hydroregime did not affect these patterns and, surprisingly, shorter hydroperiods exhibited higher regional diversity. Our results suggest that hydroregime as a single variable does not have a strong explanatory power for metacommunity assembly of temporary ponds. Therefore, a more comprehensive theory is needed to anticipate the effects of the upcoming hydroperiod shortening. [ABSTRACT FROM AUTHOR]

The latitudinal diversity gradient predicts that tropical regions should have higher alpha, beta, and gamma diversity than temperate areas. However, only a few studies have assessed the temporal variability of the different components of diversity across climatic regions. In this study, we compare, using a spatial and temporal approach, the diversity of multiple taxa inhabiting tropical and Mediterranean temporary ponds. We sampled the biological communities of each set of ponds on three occasions during the same hydrological year. Under a spatial framework, we analyzed, alpha, beta, and gamma diversities. With a temporal approach, we compared the coefficients of variation in alpha diversity for each local community, and temporal beta diversity. Differences between regions and sampling periods were tested using generalized linear mixed models. We found higher gamma and alpha diversity in the tropical ponds, as expected given the latitudinal differences between them. However, phytoplankton and microinvertebrates from the Mediterranean region, matched or even exceeded tropical alpha diversity on some occasions. Spatial beta diversity did not differ between regions, and it showed lower values at the middle or the end of the hydroperiod in bacteria, micro‐ and macroinvertebrates and amphibians. Thus, processes homogenizing and heterogenising pond metacommunities must be balanced in both studied regions. Temporal variation in alpha and beta diversity was similar for ponds in both regions, except for macroinvertebrates and amphibians, suggesting differential effects on community variation observable only in animals with longer life‐spans, at our temporal scale of analysis. [ABSTRACT FROM AUTHOR]