Habitat filtering differentially modulates phylogenetic and functional diversity relationships between predatory arthropods

Mechanisms underlying biological diversities at different scales have received significant attention over the last decades. The hypothesis whether local abiotic factors, driving functional and phylogenetic diversities, can differ among taxa of arthropods remains under-investigated. In this study, we compared correlations and drivers of functional (FD) and phylogenetic (PD) diversities between spiders and carabids, two dominant taxa of ground-dwelling arthropods in salt marshes. Both taxa exhibited high correlation between FD and PD; the correlation was even higher in carabids, probably due to their lower species richness.  Analyses highlight that FD and PD were positively linked to taxonomic diversity in both taxa; however, abiotic factors driving the FD and PD differed between spiders and carabid. Salinity particularly drove the taxonomic diversity of carabids, but not that of spiders, suggesting that spiders are phenotypically more plastic and less selected by this factor. Conversely,...