Berriasella jacobi is an extinct species of ammonite from the late Jurassic and early Cretaceous. Because of its unique stratigraphic position, it is used...

boundary has often been placed as the first appearance of the ammonite Strambergella jacobi, formerly placed in the genus Berriasella, but its use as a stratigraphic...

alpina. Some authors regard B. jacobi as instead belonging to the genus Strambergella. Berriasella, named by Uhlig, 1905, is known from the late Upper Jurassic...

boundary has often been placed as the first appearance of the ammonite Strambergella jacobi, formerly placed in the genus Berriasella, but its use as a stratigraphic...