The Triassic to Recent fossil record of the dinoflagellates is represented overwhelmingly by geologically resistant, organic‐walled, non‐motile resting cysts; such cysts are formed following the sexual phase in the life cycle. Very few confirmed records exist of the motile stage being preserved in the fossil record. This paper reports the occurrence of two very unusual dinoflagellate taphofacies, one developed in bituminous shales and the other in micrites, from the Oligocene fossil Lagerstätte at Sieblos, Hesse, Germany. A new dinoflagellate taxon, Sieblososphaera martini sp. nov. has been identified through analysis of dissociated skeletal elements in the bituminous shales and external moulds and casts in the micrites. The unique preservation of these fossils confirms them not only as primary biogenically silicified motile thecate cells, but also indicates that there was a much greater range of tabulation present within the subfamily Lithoperidiniaceae than has hitherto been recognized.

中文翻译：

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来自德国西伯斯的渐新世化石Lagerstätte的硅质鞭毛鞭毛运动细胞的独特保存

恐龙鞭毛虫的三叠纪至最近的化石记录以具有地质抵抗力，有机壁，不运动的静息囊肿为代表。这种囊肿是在生命周期的性生活阶段之后形成的。在化石记录中保存的能动阶段的确凿记录很少。本文报道了发生在德国黑森州Sieblos的渐新世化石Lagerstätte发生的两种非常不寻常的鞭毛藻类花序，一种在沥青页岩中发育，另一种在微晶岩中发育。一种新的鞭毛藻分类单元，Sieblososphaera martinisp。十一月 通过分析沥青页岩中解离的骨骼元素以及微晶岩中的外部霉菌和铸型，我们已经确定了这一点。这些化石的独特保存不仅证实它们是原生物生物硅化的运动性主题细胞，而且还表明，在远古界豆科中，存在的制表范围比迄今为止公认的范围大得多。