Reznik, S. Y. (2011). Host plant population density and distribution pattern as factors limiting geographic distribution of the ragweed leaf beetle Zygogramma suturalis F.(Coleoptera, Chrysomelidae). Entomological Review, 91(3), 292-300.

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Field sampling conducted in 2005–2007 in Voronezh and Rostov provinces and in Stavropol and Krasnodar territories (south-west of European Russia) suggested that the climatic effect on geographic distribution of the ragweed leaf beetle, Zygogramma suturalis is mediated by the abundance of its host plant, Ambrosia artemisiifolia. At the periphery of the common ragweed invasion area Z. suturalis was absent or its population density was below the detection threshold. A pivotal role was played by the sufficient percentage of small but relatively stable plots with high ragweed population density, rather than by the mean rate of the ragweed infestation. Inside the geographic range of the ragweed leaf beetle all relatively stable habitats were infested by A. artemisiifolia and in more than half of plots inspected, common ragweed percent cover was higher than 5%. In regions where such infestation was recorded on less than 20% of the plots studied, Z. suturalis was absent, most likely due to its low ability for long-range search for a host plant.