Hornung Th. (2009) "Paraspidoceras rupellense" - eine seltene Ammonitenart aus der unteren platynota -Zone (Unterstes Kimmeridgium, Alter Steinbruch Ludwag, Ofr.) // Geologische Blätter für Nordost-Bayern, Bd.59. S.221-248.
Within condensed marls and marly limestones of the basal Kimmeridgian of Southern Germany, intensely sculptured ammonites of the aspidocean subfamily Euaspidoceratinae (Spath 1931) are counted to the rarest ammonite species within this time interval. Regarding to this subfamily, only large-sized specimen with problematic affiliation to the genus »Paraspidoceras« biostratigraphically range within the lower and middle part of the platynota ammonoid zone, (polygyratus- and desmoides-ammonoid subzone; Kimmeridgian 1a1-2). Due to their rareness, the published database of those ammonites is small compared to the plethora of theses published from isochronous ammonoid species: specimens of Northern Bavaria were published exclusively from the Middle Franconian Alb (Gräfenberg- and Hartmannshof quarries, see Schlampp, 1991, 2008). So far, the Northern Franconian Alb still awaits published data of Kimmeridgian »Paraspidoceratids”. A handful specimens of »Paraspidoceras« rupellense derive from the abandoned »old« Ludwag quarry (placed on the very western edge of the Northern Franconian Alb), which became famous during the last decades due to its richness of molluscan fauna. Sized from 2 to 40 cm, the specimens derive from condensed ammonoid-rich marls of well-bedded lagoonal sediments as well as reefdetritus-facies, biostratigraphically encompassing the complete polygyratus ammonoid subzone. In the framework of facies and carbonate sedimentology, one specimen of »Paraspidoceras« rupellense and Simosphinctes (S.) tieringensis (as the presumed microconch partner to »Paraspidoceras«) were additionally described from the basal Kimmerdigian of Gräfenberg and discussed together with the Ludwag specimens.