During fieldwork near Lake Bleu, in the El Kala region of northeastern Algeria, we encountered an unfamiliar interaction between the speckled rose chafer beetle (Protaetia morio ) and the two‐tailed pasha butterfly (Charaxes jasius ). Both species are common in the Mediterranean.

Groups of around six to eight beetles were aggregating on branch crotches of a strawberry tree (Arbutus unedo ). These groups were frequently joined by one or two butterflies (https://bit.ly/3eSXHu1). We noticed that the butterflies did not land near single beetles, and from their flight patterns, they seemed to know exactly where the beetles were, as if they were attracted by chemicals.

We observed the butterflies trying to feed on something in the middle of the beetle groups. Because the two species have similar diets (nectar, ripe fruit, and tree sap), our first impression was that the butterflies were consuming tree sap in order to obtain water, amino acids, and minerals. However, we closely examined different branch crotches where the beetles congregated and found no signs of an exudate or wounds. Neither the beetle nor the butterfly has the ability to extract xylem sap by itself. Could the butterfly have been feeding on the excretions of the beetle? Why do the beetle and butterfly target branch crotches? Does this interaction involve a more complicated interspecific chemical communication between the plant and the two insect species? Future field surveys and experiments may shed light on this mystery.

在阿尔及利亚东北部El Kala地区的Bleu湖附近进行野外作业期间，我们遇到了斑点的玫瑰金龟子甲虫（Protaetia morio）和两尾巴夏蝴蝶（Charaxes jasius）之间的陌生相互作用。这两种在地中海地区都很常见。

大约六到八只甲虫聚集在草莓树的树枝c上。这些组经常由一到两只蝴蝶（https://bit.ly/3eSXHu1）加入。我们注意到蝴蝶没有降落在单个甲虫附近，并且从它们的飞行模式来看，它们似乎确切地知道了甲虫在哪里，就好像它们被化学物质吸引了一样。

我们观察到蝴蝶试图以甲虫为生。因为两个物种的饮食相似（花蜜，成熟的水果和树液），所以我们的第一印象是蝴蝶正在消耗树液以获得水，氨基酸和矿物质。但是，我们仔细检查了甲虫聚集的不同分支c，没有发现渗出液或伤口的迹象。甲虫和蝴蝶都没有能力自行提取木质部树液。蝴蝶能以甲虫的排泄物为食吗？为何甲虫和蝴蝶会瞄准branch部？这种相互作用是否涉及植物与两种昆虫物种之间更复杂的种间化学通讯？未来的现场调查和实验可能会阐明这一谜团。