The late Kimmeridgian bivalve fauna of Saal an der Donau (Bavaria, southern Germany): the Hippuritida

Five species of Hippuritida (Bivalvia: Euheterodonta) are described from the late Kimmeridgian Kelheim Member (formerly ‘Kelheimer Diceras-Kalk’, Frankenalb Formation, Weissjura Group) of Saal an der Donau, Bavaria, southern Germany. A single diceratid, Valletia auris Favre, 1927, is for the first time recorded from this area. Three species are assigned to the Epidiceratidae. Epidiceras carinatum (Gemmellaro, 1875) [synonym: Diceras bavaricum Boehm, 1881] and Plesiodiceras valfinense (Boehm, 1881) are the two most abundant species. In addition, a bizarre, bicarinate, spiraliform species is described as Saalidiceras syllai gen. et sp. nov. The fifth species, Hypelasma fritzlangi sp. nov. (Requieniidae), is sympatric with P. valfinense at Saal. The new finds document that Late Jurassic rudist faunas were more diversified than previously thought and may comprise widespread as well as potentially endemic taxa.