Bryozoa of the Murdock Mountain formation (Wordian, Permian), Leach Mountains, northeastern Nevada

A thin limestone tongue in the upper part of the Murdock Mountain Formation of northeastern Nevada contains abundant bryozoans of earliest Wordian age. This bryozoan fauna is close to the Kungurian-Kazanian boundary in Russia. These bryozoans are younger than those found in the Kaibab Formation of southern Nevada and slightly older than those in the Gerster Limestone of northern Nevada. This limestone tongue, herein referred to as the Stenodiscus beds, lies below the Thamnosia beds described by Wardlaw in the Murdock Mountain section of the Leach Mountains. This bryozoan-rich limestone tongue serves as a marker unit for mapping the Murdock Formation in the Leach Mountains.

Nine new species of bryozoans occur in the Stenodiscus beds of the Murdock Mountain Formation: Hinganella felderi, Neoeridotrypella schilti, Stenopora parvaexozona, Stenodiscus murdockensis, Dyscritella acanthostylia, Pseudobatostomella irregularis, Streblotrypa (Streblotrypa) elongata, Morozoviella praecurriensis, and Thamniscus erraticus, Hinganella felderi, Neoeridotrypella schilti, Dyscritella acanthostylia, and Streblotrypa (Streblotrypa) elongata are very similar to species described from Russia.