Upper Coniacian, Santonian, and lowermost Campanian ammonites of the Lipnik-Kije section, central Poland—taxonomy, stratigraphy, and palaeogeographic significance

The ammonites from upper Coniacian through basal Campanian of the Lipnik-Kije section (Lipnik-Kije Basin), southwestern margin of the Holy Cross Mountains, central Poland, are described in the context of its inoceramid bivalve zonation. Nineteen species-level ammonite taxa assigned to twelve genera (Gaudryceras, Saghalinites, Parapusozia, Kitchinites, Nowakites, Eupachydiscus, Protexanites, Texanites, Hyphantoceras, Glyptoxoceras, Neocrioceras, and Scaphites) are recognized. Three ammonite interval zones are distinguished. The upper Coniacian is assigned to the Paratexanites serratomarginatus and Texanites pseudotexanus zones. The lower and middle Santonian interval is assigned to a Kitchinites emscheris– Nowakites savini Zone, which is characterized by a mixed desmoceratid and pachydiscid assemblage. The upper Santonian ammonites belong to long-ranging taxa and assignment to an ammonite zone is not possible. The lower Santonian ammonite assemblages are compared with those from the Münsterland Cretaceous Basin in northern Germany and the Corbières in southern France. The co-occurrence in the Lipnik-Kije section of faunal elements from both the Boreal Realm (Münsterland Cretaceous Basin) and the Tethyan Realm (the Corbières) makes it an important section for correlation of European Santonian successions. The occurrence of Tethyan ammonites, particularly Saghalinites and Nowakites, could perhaps be explained by an incursion of warmer water masses from the Tethyan Realm into the Lipnik-Kije Basin. This suggestion is supported by unpublished oxygen stable isotope investigations of the Lipnik-Kije section which indicate relatively high sea water palaeotemperatures.