ABSTRACT In 2006, a new species of non-calcified dasycladalean alga, Chaetocladus gracilis, from the upper Silurian of Skåne (Scania), southernmost Sweden, was erected. The original description was based on a single incomplete fossil recovered from the abandoned limestone quarry at Bjärsjölagård, a classic geologic locality in Scania. Here we present four additional and, importantly, more complete specimens from this same site and type stratum. This new material largely corroborates the general anatomical features of C. gracilis, but also adds some intricate details, most notably with regards to the external sheet-like phytoleim and organisation of the laterals. Elemental mapping confirmed an expected carbonaceous composition of the fossils, which are embedded in a calcareous mudstone. These additional fossils show that the originally described specimen was not a singular occurrence at this locality. Based on the state of preservation of our algal fossils, we note that the mudstone facies of the Ludlow Bjärsjölagård Limestone Member of the Klinta Formation (Öved-Ramsåsa Group), from which all C. gracilis have been recovered, share characteristics with deposits typically referred to as “algal-Lagerstätten”.

中文翻译：

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重新审视藻类化石：来自瑞典志留纪的新材料

摘要 2006 年，来自瑞典最南端斯科讷（斯堪尼亚）上志留统的非钙化 dasycladalean 藻类新种 Chaetocladus gracilis 被建立起来。最初的描述基于从斯堪尼亚经典地质地区 Bjärsjölagård 废弃的石灰石采石场中回收的一块不完整的化石。在这里，我们展示了来自同一地点和类型地层的四个额外的，重要的是更完整的标本。这种新材料在很大程度上证实了 C. gracilis 的一般解剖特征，但也增加了一些复杂的细节，最显着的是关于外部片状植物油和侧枝的组织。元素测绘证实了化石的预期碳质成分，这些化石嵌入在钙质泥岩中。这些额外的化石表明，最初描述的标本在该地区并不是一个单一的事件。根据我们藻类化石的保存状况，我们注意到 Klinta 组（Öved-Ramsåsa 组）的 Ludlow Bjärsjölagård 石灰岩成员的泥岩相，所有 C. gracilis 都已从中恢复，与通常提到的沉积物具有相同的特征作为“algal-Lagerstätten”。