Hydroperiod and species-sorting influence metacommunity composition of crustaceans in temporary rock pools in India

Most studies on crustacean metacommunity ecology do not consider constituent higher-level taxa separately, despite ecological differences among them. This oversight, coupled with the fact that observed patterns can vary in different regions, prompted our study in the megadiverse, yet understudied, Western Ghats region in India. We studied temporary rock pools on a lateritic outcrop to identify factors influencing species richness, metacommunity structure, and spatial patterns of constituent crustacean groups. We used Spearman's correlation, ordination-based methods, partial Mantel tests, distance-decay patterns, and beta-diversity partitioning to analyse the influence of spatial and ecological factors on distribution of taxa and community composition. Overall crustacean species richness was strongly influenced by hydroperiod; some influence of other parameters such as maximum surface area and depth on species richness of individual taxa was also observed. Hydroperiod had the strongest influence on the community composition, and community dissimilarity increased with environmental and interpool distance. High turnover among the communities and significant influence of environmental factors indicated species-sorting processes were structuring the crustacean metacommunity. The communities of copepods and cladocerans showed higher nestedness while those of ostracods and large branchiopods showed higher turnover. We discuss the metacommunity structure observed at a small spatial scale in relation to the ecology of constituent crustacean groups, habitat, and landscape features.