Sachs, S. & Hornung, J. J. (2015) Marine tetrapods from the Middle Jurassic (Aalenian and Bajocian) of Bielefeld (northwest Germany). Berichte Naturwissenschaftlicher Verein für Bielefeld und Umgegend 53: 52-73.
—Hitherto unpublished marine tetrapod remains from the Upper Aalenian (Ludwigienton-Formation) and Upper Bajocian (Parkinsonienton-Formation) of Bielefeld-Bethel are described. Both stratigraphic intervals contain remains of thalattosuchians, ichthyosaurians and plesiosaurians, which indicate the persistence of faunal assemblages similar to those from distal basinal settings of the Lower Jurassic into the Middle Jurassic. This is of special importance since marine tetrapod remains are generally rare in the Aalenian and Bajocian of Central Europe. The strata containing both assemblages were deposited under transgessive to highstand systems tract conditions.
