Systematics of Sphecidae sensu lato : Past, Present, and Future—Quantifying Diversity, Taxonomy, and Phylogeny

Abstract Sphecidae sensu lato (s.l.) currently comprises 13 families and over 10,000 described species. Together with bees, they form the monophyletic superfamily Apoidea. Collectively referred to as spheciformes, digger wasps, and apoid wasps, they are known for provisioning their larvae with hunted arthropods. Uncertainties in their relationships stem from non-monophyly, unsequenced taxa, and limited integration of phylogenetic data with morphological synapomorphies, ecology, and behavior. Continued systematics work across taxonomic levels, particularly intrageneric and within newly recognized families, will bring us closer to understanding the evolutionary history, diversification patterns, and adaptations that have shaped these wasps. In addition to their tree of life, nesting biology and prey specificity is known for only around half of the genera, many of which have assumed diets based on records from a single species. To review the landscape of Sphecidae s.l. systematics, we mined the literature and primarily extracted data from two of the most robust resources: Drs. Richard Bohart and Arnold Menke’s 1976 book, Sphecid Wasps of the World, and Dr. Wojciech Pulawski’s web-based Catalog of Sphecidae. This resulted in quantification of phylogenetic and taxonomic effort, extant and extinct species richness, behavior, and distribution. Our review highlights areas and groups in need of research, biases due to where specimens are held and experts are based, and a detailed foundation for what lies at the next Sphecidae s.l. frontier.