Two fossil March flies (Insecta, Diptera, Bibionidae) are recorded from open lake deposits of the middle Miocene Gračanica mine near Bugojno in Bosnia and Herzegovina. These two fossils represent the first insects found in this outcrop. One specimen is described as Plecia sp. indet, the other as Bibio sp. indet. The incomplete preservation does not allow for species descriptions, but the specimens seem not to be conspecific with any known fossil bibionids. The habitus and colouration of the Bibio specimen is very similar to the recent species Bibio hortulanus (Linnaeus). The presence of the genus Plecia is considered to indicate warm climate, while Bibio points more to a temperate climate. But for reliable conclusions on the climate, much more records of bibionid fossils would be needed.

中文翻译：

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始于中新世Gračanica矿（波斯尼亚和黑塞哥维那布戈尼诺）的三月苍蝇（昆虫：双翅目：双足纲）的第一记录

在波斯尼亚和黑塞哥维那布戈尼诺附近的中新世中新世Gračanica矿山的露天湖泊沉积物中记录了两只化石三月的苍蝇（昆虫纲，双翅目，Bibion​​idae）。这两个化石代表了该露头中发现的第一批昆虫。一种标本被描述为Plecia sp。indet，另一个为Bibio sp。indet。保存不完全不允许对物种进行描述，但标本似乎与任何已知的化石重生生物都没有特异性。Bibio标本的习性和颜色与最近的Bibio hortulanus（Linnaeus）物种非常相似。Plecia属的存在表明气候温暖，而Bibio指向温带气候。但是，要想得出可靠的气候结论，还需要更多的双性类化石记录。