The early wasp plucks the flower: Disparate extant diversity of sawfly superfamilies (Hymenoptera: 'Symphyta') may reflect asynchronous switching to angiosperm hosts

Research output: Contribution to journalArticle


The insect order Hymenoptera originated during the Permian nearly 300 Mya. Ancestrally herbivorous hymenopteran lineages today make up the paraphyletic suborder 'Symphyta', which encompasses c. 8200 species with very diverse host-plant associations. We use phylogeny-based statistical analyses to explore the drivers of diversity dynamics within the 'Symphyta', with a particular focus on the hypothesis that diversification of herbivorous insects has been driven by the explosive radiation of angiosperms during and after the Cretaceous. Our ancestral-state estimates reveal that the first symphytans fed on gymnosperms, and that shifts onto angiosperms and pteridophytes - and back - have occurred at different time intervals in different groups. Trait-dependent analyses indicate that average net diversification rates do not differ between symphytan lineages feeding on angiosperms, gymnosperms or pteridophytes, but trait-independent models show that the highest diversification rates are found in a few angiosperm-feeding lineages that may have been favoured by the radiations of their host taxa during the Cenozoic. Intriguingly, lineages-through-time plots show signs of an early Cretaceous mass extinction, with a recovery starting first in angiosperm-associated clades. Hence, the oft-invoked assumption of herbivore diversification driven by the rise of flowering plants may overlook a Cretaceous global turnover in insect herbivore communities during the rapid displacement of gymnosperm- and pteridophyte-dominated floras by angiosperms.


  • Tommi Nyman
  • Renske E. Onstein
  • Daniele Silvestro
  • Saskia Wutke
  • Andreas Taeger
  • Niklas Wahlberg
  • Stephan M. Blank
  • Tobias Malm
External organisations
  • Norwegian Institute of Bioeconomy Research (Nibio)
  • University of Eastern Finland
  • University of Gothenburg
  • Swedish Museum of Natural History
  • German Centre for Integrative Biodiversity Research (iDiv)
  • Senckenberg German Entomological Institute
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Ecology


  • diversification rates, flowering plants, insect-plant interactions, macroevolution, mass extinctions
Original languageEnglish
Number of pages19
JournalBiological Journal of the Linnean Society
Publication statusPublished - 2019 Aug 14
Publication categoryResearch