Longhorn beetles are commonly moved among continents within wood packaging materials used in trades. Visual inspections carried out at points of entry often fail to detect exotic longhorn beetles as infested materials may have little or no sign of colonization. Black-colored traps baited with pheromones and host volatiles are thus used to improve chances of detection. Here we tested whether existing surveillance protocols for longhorn beetles can be further improved using trap colors different than black. Baited traps of eight different colors (i.e., grey, yellow, green, red, blue, brown, purple and black) were deployed in a randomized complete block design at 16 sites in northern Italy in 2019. A total of 6,001 individuals from 56 longhorn beetle species were trapped. In general, yellow and blue traps caught a significantly higher number of longhorn beetle species than black traps. In addition, trap color significantly affected species richness and abundance at the subfamily and species level, with mixed response mostly linked to the habit of visiting flowers for food. Flower-visiting longhorn beetles mainly exhibited clear preference for flower-related colors, i.e., yellow, green and blue, whereas non-flower-visiting species were more attracted by dark and long-wavelength-dominated colors, like red and brown. Our results clearly indicate that generic surveillance programs should not rely exclusively on black traps and that the use of more trap colors can strongly improve the chance of detecting native and exotic longhorn beetles potentially moved with trades.

长角甲虫通常在各行各业使用的木质包装材料中在各大洲之间移动。在入口处进行的目视检查通常无法检测到异国长角甲虫，因为被感染的材料可能几乎没有定植的迹象。因此，诱集有信息素和宿主挥发物的黑色诱集装置可用于提高检测机会。在这里，我们测试了使用不同于黑色的陷阱颜色是否可以进一步改善针对长角甲虫的现有监视协议。八种不同颜色（即灰色，黄色，绿色，红色，蓝色，棕色，紫色和黑色）的诱饵陷阱于2019年在意大利北部的16个地点进行了随机完整块设计。来自56个长角牛的6,001个人甲虫被困住了。一般来说，黄色和蓝色陷阱捕获的长角甲虫种类明显多于黑色陷阱。此外，陷阱颜色在亚科和物种水平上显着影响物种的丰富度和丰度，而不同的反应大多与拜访花卉作为食物的习惯有关。访花长角甲虫主要表现出明显的与花朵相关的颜色，即黄色，绿色和蓝色，而不访花的甲虫则更受深色和长波长为主的颜色（如红色和棕色）的吸引。我们的结果清楚地表明，通用监视程序不应该仅依赖于黑色陷阱，而使用更多的陷阱颜色可以极大地提高检测可能因交易而移动的本地和外来长角甲虫的机会。陷阱颜色在亚科和物种水平上显着影响了物种的丰富度和丰度，而不同的响应大多与拜访花卉作为食物的习惯有关。访花长角甲虫主要表现出明显的与花朵相关的颜色，即黄色，绿色和蓝色，而不访花的甲虫则更受深色和长波长为主的颜色（如红色和棕色）的吸引。我们的结果清楚地表明，通用监视程序不应该仅依赖于黑色陷阱，并且使用更多的陷阱颜色可以大大提高检测到可能随行业转移的本地和外来长角甲虫的机会。陷阱颜色在亚科和物种水平上显着影响了物种的丰富度和丰度，而不同的响应大多与拜访花卉作为食物的习惯有关。访花长角甲虫主要表现出明显的与花朵相关的颜色，即黄色，绿色和蓝色，而不访花的甲虫则更受深色和长波长为主的颜色（如红色和棕色）的吸引。我们的结果清楚地表明，通用监视程序不应仅依赖于黑陷阱，并且使用更多的陷阱颜色可以极大地提高检测可能随贸易而移动的本地和外来长角甲虫的机会。访花长角甲虫主要表现出明显的与花朵相关的颜色，即黄色，绿色和蓝色，而不访花的甲虫则更受深色和长波长为主的颜色（如红色和棕色）的吸引。我们的结果清楚地表明，通用监视程序不应该仅依赖于黑色陷阱，并且使用更多的陷阱颜色可以大大提高检测到可能随行业转移的本地和外来长角甲虫的机会。访花长角甲虫主要表现出明显的与花朵相关的颜色，即黄色，绿色和蓝色，而不访花的甲虫则更受深色和长波长为主的颜色（如红色和棕色）的吸引。我们的结果清楚地表明，通用监视程序不应该仅依赖于黑色陷阱，并且使用更多的陷阱颜色可以大大提高检测到可能随行业转移的本地和外来长角甲虫的机会。