Surrogates of spider diversity, leveraging the conservation of a poorly known group in the Savanna Biome of South Africa

► Generic richness was the most efficient surrogate of spider diversity. ► The two-indicator group, Salticidae and Thomisidae, was the most efficient cross taxon surrogate. ► Woody vegetation and birds (non-overlapping indicator groups) performed poorly. ► Use of morphospecies as surrogates are cautiously supported but not preferred.