Konservat‐Lagerstätten are seen as snapshots of past biodiversity for a given location and time. However, processes leading to the exceptional morphological preservation of fossils in these deposits remain incompletely understood. This results in a deficient assessment of taphonomic biases and limits the robustness/relevance of palaeobiological reconstructions. Here, we report the mineralogical characterization of crustacean fossils preserved within carbonate‐rich concretions from the Jurassic Konservat‐Lagerstätte of La Voulte‐sur‐Rhône (Ardèche, France). The combination of SEM‐EDS, TEM, synchrotron‐based XRF, XRD and XANES allows the mineralogical phases composing these fossils (i.e. fluorapatite, Fe‐sulfides (pyrite, pyrrhotite) and Mg‐calcite) and the surrounding matrix (i.e. Mg‐calcite, clays and detrital silicates) to be identified. Fluorapatite and pyrite (and pyrrhotite) precipitated during decay under anoxic conditions, replacing delicate organic structures and preserving anatomical details. These mineral structures were subsequently consolidated by a Mg‐calcite cement. Of note, histologically similar tissues were replaced by the same mineral phases, confirming that fossilization (in La Voulte) occurred rapidly enough to be influenced by tissue composition. Altogether, the present study shows that exceptional preservation requires fast biodegradation, thereby confirming recent experimental evidence.

中文翻译：

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特殊的保存需要快速的生物降解：来自拉沃洛特河畔罗讷河谷的噻头颅标本（卡洛维安，侏罗纪，法国）

Konservat-Lagerstätten被视为给定位置和时间的过去生物多样性的快照。然而，导致这些矿床中化石异常形态保存的过程仍不完全清楚。这导致对系统语言偏倚的评估不足，并限制了古生物学重建的健壮性/相关性。在这里，我们报告了LaVoulte-sur-Rhône的侏罗纪Konservat-Lagerstätte（法国，阿德什）的富含碳酸盐岩中保存的甲壳类化石的矿物学特征。SEM-EDS，TEM，基于同步加速器的XRF，XRD和XANES的组合允许组成这些化石的矿物学相（即氟磷灰石，硫化铁（黄铁矿，黄铁矿）和镁方解石）和周围的基质（即镁方解石） ，粘土和碎屑硅酸盐）。氟磷灰石和黄铁矿（和黄铁矿）在缺氧条件下的腐烂过程中沉淀，取代了精细的有机结构并保留了解剖结构。这些矿物结构随后通过镁方解石水泥固结。值得注意的是，组织学上相似的组织被相同的矿物质相所替代，这证实了化石（在La Voulte中）发生得足够快，足以受到组织成分的影响。总而言之，本研究表明特殊的保存要求快速的生物降解，从而证实了最近的实验证据。组织学上相似的组织被相同的矿物质相所替代，这证实了化石（在La Voulte中）发生得很快，足以受到组织成分的影响。总而言之，本研究表明特殊的保存要求快速的生物降解，从而证实了最近的实验证据。组织学上相似的组织被相同的矿物质相所替代，这证实了化石（在La Voulte中）发生得很快，足以受到组织成分的影响。总而言之，本研究表明特殊的保存要求快速的生物降解，从而证实了最近的实验证据。