Beetles of the family Lycidae have long been known to be chemically protected. We present evidence that North American species of the lycid genera Calopteron and Lycus are rejected by thrushes, wolf spiders, and orb-weaving spiders, and that they contain a systemic compound that could account, at least in part, for this unacceptability. This compound, a novel acetylenic acid that we named lycidic acid, proved actively deterrent in feeding tests with wolf spiders and coccinellid beetles.Species of Lycus commonly figure as models of mimetic associations. Among their mimics are species of the cerambycid beetle genus Elytroleptus, remarkable because they prey upon the model lycids. We postulated that by doing so Elytroleptus might incorporate the lycidic acid from their prey for their own defense. However, judging from analytical data, the beetles practice no such sequestration, explaining why they remain relatively palatable (in tests with wolf spiders) even after having fed on lycids. Chemical analyses also showed the lycids to contain pyrazines, such as were already known from other Lycidae, potent odorants that could serve in an aposematic capacity to forestall predatory attacks.

中文翻译：

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Lycid 甲虫和以它们为食的拟天牛甲虫的防御化学。

长期以来，人们都知道 Lycidae 科的甲虫受到化学保护。我们提供的证据表明，北美的 lycid 属 Calopteron 和 Lycus 物种被画眉、狼蛛和圆蛛拒绝，并且它们含有一种全身性化合物，至少可以部分解释这种不可接受性。这种化合物是一种我们命名为lycidic acid 的新型炔酸，在狼蛛和瓢虫的喂养测试中证明具有积极的威慑作用。 Lycus 物种通常被视为模拟关联的模型。它们的模仿物包括天牛甲虫属 Elytroleptus 的物种，这很了不起，因为它们捕食模型 lycids。我们推测，通过这样做，Elytroleptus 可能会从它们的猎物中吸收水杨酸以进行自我防御。但从分析数据来看，甲虫没有进行这种隔离，这解释了为什么即使在以枸橼酸为食后它们仍然相对可口（在狼蛛的测试中）。化学分析还表明，这些荔枝中含有吡嗪，就像其他荔枝科中已知的一样，这是一种有效的气味剂，可以起到阻止掠食性攻击的净化能力。