Changes in life history traits are often considered speciation triggers and can have dramatic effects on the evolutionary history of a lineage. Here, we examine the conse-quences of changes in two life history traits, host-type and phoresy, in the hypermeta-morphic blister beetles, Meloidae. Subfamilies Nemognathinae and Meloinae exhibit a complex life cycle involving multiple metamorphoses and parasitoidism. Most gen-era and tribes are bee- parasitoids, and include phoretic or nonphoretic species, while two tribes feed on grasshopper eggs. These different life strategies are coupled with striking differences in species richness among clades. We generated a mitogenomic phylogeny for Nemognathinae and Meloinae, confirming the monophyly of these two clades, and used the dated phylogeny to explore the association between diver-sification rates and changes in host specificity and phoresy, using state-dependent speciation and extinction (SSE) models that include the effect of hidden traits. To account for the low taxon sampling, we implemented a phylogenetic-taxonomic ap-proach based on birth-death simulations, and used a Bayesian framework to integrate parameter and phylogenetic uncertainty. Results show that the ancestral hypermet-amorphic Meloidae was a nonphoretic bee- parasitoid, and that transitions towards a phoretic bee- parasitoid and grasshopper parasitoidism occurred multiple times. Nonphoretic bee- parasitoid lineages exhibit significantly higher relative extinction and lower diversification rates than phoretic bee-and grasshopper- parasitoids, but no significant differences were found between the latter two strategies. This suggests that Orthopteran host shifts and phoresy contributed jointly to the evolutionary suc-cess of the parasitoid meloidae. We also demonstrate that SSE models can be used to identify hidden traits coevolving with the focal trait in driving a lineage's diversifica-tion dynamics.