Abstract Two species of silver fly, Leucopis argenticollis (Zetterstedt) and Leucopis piniperda (Malloch) (Diptera: Chamaemyiidae), from the Pacific Northwest region of North America have been identified as potential biological control agents of hemlock woolly adelgid (Hemiptera: Adelgidae: Adelges tsugae Annand) in eastern North America.The two predators are collectively synchronized with A. tsugae development.To determine whether adult emergence of the two species of silver fly are also synchronized with one another, we collected adult Leucopis which emerged from A. tsugae-infested western hemlock [Pinaceae: Tsuga heterophylla (Raf.) Sarg.] from four sites in the Pacific Northwest over a 29-d period. Specimens were collected twice daily in the laboratory and identified to species using DNA barcoding. The study found that more adult Leucopis were collected in the evening than the morning. Additionally, the daily emergences of adults over the 29-d sampling period exhibited sinusoidal-like fluctuations of peak abundance of each species, lending evidence to a pattern of temporal partitioning.This pattern could have logistical implications for their use as biological control agents in eastern North America, namely the need to release both species for maximum efficacy in decreasing A. tsugae populations.

中文翻译：

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Leucopis argenticollis 和 Leucopis piniperda（双翅目：Chamaemyiidae），铁杉羊毛 Adelgid（半翅目：Adelgidae）的捕食者之间成虫出现的时间不同步，对生物控制的影响

摘要 来自北美太平洋西北部地区的两种银蝇，银蝇（Leucopis argenticollis (Zetterstedt) 和 Leucopis piniperda (Malloch)（双翅目：Chamaemyiidae）已被鉴定为铁杉毛蝇科（Hemiptera：Adelgidae：Adelges）的潜在生物防治剂。 tsugae Annand) 在北美东部。这两种捕食者共同与 A. tsugae 发育同步。为了确定这两种银蝇的成虫出现是否也同步，我们收集了从 A. tsugae 出现的成虫 Leucopis-在 29 天的时间里，来自太平洋西北部四个地点的受侵染的西部铁杉 [松科：Tsugaheterophylla (Raf.) Sarg.]。实验室每天收集两次样本，并使用 DNA 条形码识别物种。研究发现，在晚上收集到的成虫比早上多。此外，在 29 天采样期内，成虫的每日出现表现出每个物种峰值丰度的正弦状波动，为时间分区模式提供证据。这种模式可能对它们在东部用作生物控制剂具有后勤意义北美，即需要释放这两种物种以在减少 A. tsugae 种群方面发挥最大功效。