Herbivore insects use a variety of search cues during host finding and mate recognition, including visual, gustatory, and olfactory stimuli, leaving multiple traits for evolution to act upon. However, information about differences or similarities in search pattern amongst closely related insect herbivore species is still scarce. Here, we study the production of and the response to pheromone in Galerucella (Coleoptera: Chrysomelidae) to investigate the beetles’ search behaviour. Males of G. pusilla and G. calmariensis, two closely related species, are known to produce the aggregation pheromone dimethylfuran-lactone when feeding on their host plant, whereas no pheromones have been identified in other Galerucella species. We show that dimethylfuran-lactone is produced also by males of G. tenella, a species phylogenetically close to G. pusilla and G. calmariensis, whereas the more distantly related species G. lineola and G. sagittariae were not found to produce the same compound. To investigate the beetles’ behavioural response to dimethylfuran-lactone, the pheromone was synthesized using a partly novel method and tested in olfactometers, showing that G. pusilla, G. calmariensis, and G. tenella were all attracted to the pheromone, whereas G. lineola and G. sagittariae did not respond. This suggests that the production of and the response to pheromone could be linked to the phylogenetic relatedness between the species.

中文翻译：

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化学通讯和寄主搜索Galerucella叶甲虫。

草食性昆虫在寄主发现和配偶识别过程中使用各种搜索线索，包括视觉，味觉和嗅觉刺激，从而留下了多种进化特征。但是，关于紧密相关的昆虫食草动物物种在搜索方式上的差异或相似性的信息仍然很少。在这里，我们研究了Galerucella（鞘翅目：菊科）中信息素的产生和响应，以调查甲虫的搜索行为。G的雄性。已知两个近缘种pusilla和G. Calariensis会以其寄主植物为食而产生聚集信息素二甲基呋喃内酯，而其他Galerucella中未发现信息素种类。我们表明，二甲基呋喃内酯也是由G的雄性产生的。tenella，在系统发育上接近G的物种。pusilla和G ^。谷胱甘肽（Calariariensis），而远缘相关的物种G. lineola和G. sagittariae则未产生相同的化合物。调查甲虫至甲基呋喃内酯行为反应，信息素是使用部分地新颖方法合成和测试olfactometers，可见ģ。pusilla，ģ。calmariensis，和G ^。Tenella都吸引到信息素，而G ^。lineola和G ^。射手座没有回应。这表明信息素的产生和对信息素的反应可能与物种之间的系统发育相关性有关。