Location: Systematic Entomology LaboratoryTitle: Leaf beetles are ant-nest beetles: the curious life of the juvenile stages of case-bearers (Coleoptera, Chrysomelidae, Cryptocephalinae) Author
Submitted to: ZooKeys
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/10/2015
Publication Date: 12/17/2015
Citation: Agrain, F.A., Buffington, M.L., Chaboo, C.S., Chamorro, M.L., Scholler, M.S. 2015. Leaf beetles are ant-nest beetles: the curious life of the juvenile stages of case-bearers (Coleoptera, Chrysomelidae, Cryptocephalinae). ZooKeys. 547:133-164. Interpretive Summary: Leaf beetles and ants and wasps are among the most important insects for U.S. agriculture. Many leaf beetles are serious pests, feeding on crops and destroying valuable plants, particularly in the larval stages; others are important biological control agents that can be used to control unwanted weeds. This works synthesizes our knowledge about the relationship between ants, parasitoid wasps, and beetles with discussion on the evolution of this interesting behavior and interdependency of these various insect groups. This contribution should stimulate future research on ant loving beetles, their parasitoid wasps. This publication will be useful to biological control workers, taxonomists, ecologists, conservation biologists, coleopterists, morphologists and those interested in plant-feeding beetles.
Technical Abstract: Although some species of Cryptocephalinae (Coleoptera: Chrysomelidae) have been documented with ants (Hymenoptera: Formicidae) for almost 200 years, information on this association is fragmentary. This contribution synthesizes scattered literature to determine the patterns in ant host use. Some degree of myrmecophily is documented for 34 species in 14 of the 127 recognized genera of Cryptocephalinae, this represents ~14 % of the genera, and 0.6 % of the species diversity of the subfamily. At the generic level myrmecophily is more common in the tribe Clytrini (19%) than within Cryptocephalini (11%). No records were found to suggest ant associations for the cryptocephaline Fulcidacini or the closely-related Lamprosomatinae. Analysis of the available records revealed several noteworthy biogeographical ecological, and evolutionary patterns of leaf beetle-ant associations. Myrmecophilous cryptocephalines select formicine and myrmecines ant hosts. These two ant lineages are sister-groups with their root-node dated about 77–82 mya. In the New World tropics, the relatively recent radiation of ants from moist forests to more xeric ecosystems might have propelled this association of cryptocephalines and ant nests. Literature records suggest that the defensive behavioral profile or chemical profile (or both) of these ants has been exploited by cryptocephalines. The literature synthesis also revealed specialized predators, especially parasitoid Hymenoptera, that exploit cryptocephaline beetles inside the ant nests. We estimate the origin of cryptocephaline myrmecophily to the upper Cretaceous or later based on the minimum age of a fossil larva dated to 45 mya, although uncertainty exist, mainly due to incongruence of current studies on the origin of Chrysomelidae and angiosperm-associated lineages as cryptocephalines. Living with ants offers multiple advantages that might have aided the colonization of some cryptocephaline species in xeric environments.