- © 2014 UW Department of Geology and Geophysics
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 Merrilina praedivergens (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.