UV-light-induced fluorescence is widely used in the study of coal macerals and palynological samples, but to date has not been described in great detail for plant macrofossils. Here, we report the characteristics of bright UV-light-induced fluorescence of various fossil angiosperm leaf taxa from the Upper Pliocene of Willershausen, Lower Saxony, Germany. The fluorescence is exceptional, since different fluorescence colors ranging from green to yellow to red can be observed and fluorescence properties are found to be related to genera. Using confocal laser scanning microscopy, fluorescence was studied in detail and emission spectra were obtained that allowed to differentiate broad groups of fluorophores. Fluorescence emissions attributed to chlorophyll degradation products demonstrate that fluorescence can be used as an indicator for exceptional chemical preservation of leaf fossils. Comparison with present-day senescing plants suggests that the fluorescence differences in the fossil leaves are mainly caused by taxon-specific degeneration of organic compounds during senescence. The occurrence of various leaf taxa with different fluorescence properties, preserved under identical conditions of fossilization, indicate that diagenesis was not crucial for the differences in leaf fluorescence.

紫外线诱导的荧光已广泛用于煤化学成分和孢粉样品的研究，但迄今为止，尚未对植物大型化石进行详细描述。在这里，我们报告了来自德国下萨克森州Willershausen的上新世的各种化石被子植物叶类群的明亮的紫外线诱导的荧光特征。荧光是特殊的，因为可以观察到从绿色到黄色再到红色的不同荧光颜色，并且发现荧光性质与属有关。使用共聚焦激光扫描显微镜，对荧光进行了详细研究，并获得了可区分宽泛荧光团的发射光谱。归因于叶绿素降解产物的荧光发射表明，荧光可以用作指示叶化石异常化学保存的指标。与当今衰老植物的比较表明，化石叶片中的荧光差异主要是由衰老过程中有机化合物的分类群特异性变性引起的。在相同的化石条件下保存的具有不同荧光特性的各种叶类群的出现，表明成岩作用对于叶荧光的差异不是至关重要的。