Permian fauna of the Los Arcos Formation, Municipality of Olinalá, State of Guerrero, Mexico

Abstract

This paper documents the faunal assemblage of the Los Arcos Formation, in the Olinalá region, in northeastern State of Guerrero. A Middle Permian age is assigned based on ammonoids.

The illustrated brachiopods are Orbiculoidea ovalis Cloud, Thamnosia depressa (Cooper), Spiriferellina cristata (Von Schlotheim), Cancrinella rugosa Cloud, Leiorhynchoidea schucherti Cloud, Krotovia sp., Wellerella sp., Hustedia sp., Composita sp., Costiferina sp.; the gastropod Babylonites carinatus Yochelson; the nautiloids Bitaunioceras coahuilensis Miller and Metacoceras sp.; the ammonoids Paraceltites elegans Girty, Waagenoceras dieneri Böse, Pseudogastrioceras roadense (Böse), and Stacheoceras toumanskyae Miller and Furnish; the pelecypod Posidoniella sp.; columnals of the crinoid Preptoprennum rugosum Moore and Jeffords; and the conulariid Paraconularia sp... In order to continue, download full text in PDF.