Divergence estimates and new insights into the early evolution of cynipoid wasps (Hymenoptera)

The Cynipoidea, generally known as the gall wasps, possess a broad range of biological attributes, ranging from primary and hyper parasitization, to gall induction and inquillinism. We explore the early phylogenetic branching patterns of the cynipoids, and in the process, estimate non clock-like divergence times for all the major lineages. Recent work on fossil cynipoids has provided calibration points for our analyses. Our results estimate the median age of the branch leading to the root of the Cynipoidea to be 130 million years old, the branch leading to the true gall wasps (Cynipidae) to be 54 million years old, and the branch leading to the entomophagous Figitidae to be 105 million years. Given these dates, and the estimated divergence estimates for the hosts of cynipoid wasps (both plants and other insects), we build on previous hypotheses that the gall wasps are a derived, phytophagous lineage nested within the largely parasitic Cynipoidea, and that major lineages of Figitidae chronologically ‘tracked’ the divergence times of their hosts.