Middle Triassic ammonites from Sonora, México
Middle Triassic ammonites identified as cf. Paracrochordiceras sp. and Paranevadites cf. P. furlongi (Smith) are documented from a 180 m thick interval of sandstone, siltstone and limestone in the lower part of the Antimonio Formation in the Sierra del Álamo Muerto, in northwestern Sonora, Mexico… in order to continue, download the full paper in PDF.