Abundant bryozoans occur in the uppermost Gerster Limestone (Permian) in a saddle directly west of the main Medicine Range section of the Gerster Limestone of northeastern Nevada. The stratigraphic position of this shaly limestone is confirmed by the conodont Merrilinapraedivergens (late Wordian), which occurs elsewhere in the uppermost Gerster Limestone. Three new genera and five new species of bryozoans have been discovered in this shaly limestone. Subsequent analyses identified the new genera as Autospinifera n. gen., Utgaardostylus n. gen., and Wyseotrypa n. gen. The new species are Autospinifera rossae n. sp., Utgaardostylus stylata n. sp., Wyseotrypa parallela n. sp., Dyscritella triangulara n. sp., and Dyscritellina laminata n. sp. Other species of bryozoans present were previously described from the Russian Far East, Murdock Mountain Formation of the Leach Mountains of northeastern Nevada, Phosphoria Formation of eastern Idaho, and Gerster Limestone of the Medicine Range section of Nevada. This bryozoan fauna represents a late middle-Permian boreal fauna.
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机译：丰富的苔藓虫出现在内华达州东北部Gerster石灰岩主要Medicine Range部分正西侧的马鞍上最上层的Gerster石灰岩（二叠纪）。这种页岩石灰岩的地层位置由conodont Merrilinapraedivergens（Wordian晚期）证实，它出现在最上层的Gerster石灰岩的其他地方。在这片页岩石灰岩中发现了三个新属和五个新种的苔藓动物。随后的分析将新属确定为Autospinifera n. gen.、Utgaardostylus n. gen.和Wyseotrypa n. gen.。新种为Autospinifera rossae n. sp.、Utgaardostylus stylata n. sp.、Wyseotrypa parallela n. sp.、Dyscritella triangulara n. sp.和Dyscritellina laminata n. sp.。其他种类的苔藓虫以前在俄罗斯远东地区、内华达州东北部利奇山脉的默多克山地层、爱达荷州东部的磷化地层和内华达州梅迪奇山脉部分的格斯特石灰岩中被描述过。这种苔藓动物群代表了二叠纪中期晚期的北方动物群。
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