Caterpillars of the Alcon blue butterfly Phengaris alcon are initially endophytic and feed inside the flowerheads of Gentiana plants, but complete their development as social parasites in the nests of Myrmica ants, where they are fed by workers. Its specific and complicated ecological requirements make P. alcon a very local, threatened species, sensitive to environmental changes. We investigated an isolated and previously unknown population in an area of high nature value—the Białowieża Forest (NE Poland). Using the mark–release–recapture method we estimated the seasonal number of adults at 1460 individuals, and their density (850/ha) was the highest among all populations using G. pneumonanthe studied so far. The site is also unique due to the presence of the specific parasitoid Ichneumon cf. eumerus, and parasitoids are considered the ultimate indicators of the biodiversity of Phengaris systems. Since 75.5% of P. alcon pupae were infested we could estimate the seasonal population of adult wasps at about 4500 individuals. The high abundance of both P. alcon and its parasitoid may be explained by favorable habitat characteristics, i.e., the strong presence of host plants and the high density of nests of Myrmica scabrinodis, which is the only local host ant of the butterfly.

中文翻译：

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独特地区中的独特种群：Białowieża森林中的爱尔康蓝蝴蝶及其特定的寄生虫

Alcon蓝蝴蝶Phengaris alcon的毛毛虫最初是内生的，以Gentiana植物的花冠为食，但在Myrmica蚂蚁巢中作为社交寄生虫完成了它们的发育，并由工人喂养。由于其特殊而复杂的生态要求，使爱尔康假单胞菌成为非常局部的，受威胁的物种，对环境变化敏感。我们调查了自然价值较高的地区Białowieża森林（波兰东北部）中一个孤立的且先前未知的种群。使用标记-释放-捕获方法，我们估计了成年人的季节性数量为1460个，其密度（850 / ha）在使用肺气单胞菌的所有人群中最高。到目前为止研究。由于存在特定的寄生性寄生虫Ichneumon cf ，因此该位点也是独特的。Eumrus和寄生虫被认为是Phengaris系统生物多样性的最终指标。由于有75.5％的爱尔康假单胞菌受到侵染，我们可以估计成年黄蜂的季节性种群约为4500人。P. alcon和其寄生虫的丰度都可以通过有利的栖息地特征来解释，即寄主植物的强烈存在和Myrmica scabrinodis巢的高密度，这是蝴蝶的唯一地方寄主。