The striped cucumber beetle, Acalymma vittatum (Fabricius), is an important pest of cucurbit production in the eastern United States, where most commercial producers rely on insecticides to control this pest species. Biological control provides an alternative to insecticide use, but for A. vittatum, top-down control has not been well developed. In the northeastern United States, two parasitoid species, Celatoria setosa (Coquillett) (Diptera: Tachinidae) and Centistes diabroticae (Gahan) (Hymenoptera: Braconidae) have been reported from A. vittatum, but their distribution is poorly known. To determine whether these parasitoid species are attacking A. vittatum in Pennsylvania and the amount of mortality they provide, we characterized the parasitoid dynamics in two distinct efforts. First, we reared parasitoids from beetles captured at two research farms. Second, we focused on one of these farms and dissected beetles to quantify both parasitoid and parasite species attacking A. vittatum. Both efforts confirmed Cl. setosa and Cn. diabroticae, and parasitism rates varied widely between locations and among years (4-60%). Unexpectedly, our dissections revealed that a potentially undescribed nematode species (Howardula sp.) as the most common parasite in the community. We also discovered gregarine protists. Despite being smaller than females, males were more commonly attacked by parasitic species, but we detected no relationship between the size of beetles and abundance of parasitic species in A. vittatum. This work provides a baseline understanding of the parasitoid and parasite community attacking A. vittatum and advances opportunities for conservation biological control using these natural-enemy species.

中文翻译：

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条纹黄瓜甲虫（鞘翅目：Chrysomelidae）种群中的寄生物、线虫和原生生物

条纹黄瓜甲虫 Acalymma vittatum (Fabricius) 是美国东部葫芦科生产的重要害虫，大多数商业生产者依靠杀虫剂来控制这种害虫种类。生物防治提供了一种替代杀虫剂使用的方法，但对于 A. vittatum，自上而下的防治尚未得到很好的发展。在美国东北部，已从 A. vittatum 报道了两种寄生蜂，Celatoria setosa (Coquillett) (双翅目：Tachinidae) 和 Centistes diabroticae (Gahan)（膜翅目： Braconidae），但它们的分布知之甚少。为了确定这些寄生蜂物种是否正在攻击宾夕法尼亚州的 A. vittatum 以及它们提供的死亡率，我们在两个不同的努力中对寄生蜂动态进行了表征。第一的，我们从两个研究农场捕获的甲虫中饲养了拟寄生物。其次，我们专注于这些农场之一并解剖甲虫，以量化攻击 A. vittatum 的拟寄生物和寄生物物种。这两项努力都证实了 Cl。setosa 和 Cn。diabroticae 和寄生率在不同地点和年份之间差异很大（4-60%）。出乎意料的是，我们的解剖揭示了一种可能未被描述的线虫物种（Howardula sp.）是社区中最常见的寄生虫。我们还发现了群居原生生物。尽管比雌性小，雄性更容易受到寄生物种的攻击，但我们发现甲虫的大小与 A. vittatum 中寄生物种的丰度之间没有关系。这项工作提供了对寄生蜂和寄生蜂群攻击 A.