Klug Christian, Etter Walter, Hoffmann René, Fuchs Dirk, De Baets Kenneth
Paläontologisches Institut und Museum, Universität Zürich, Karl-Schmid-Strasse 4, Zurich, 8006 Switzerland.
Naturhistorisches Museum Basel, Augustinergasse 2, Basel, 4001 Switzerland.
Swiss J Palaeontol. 2020;139(1):7. doi: 10.1186/s13358-020-00207-7. Epub 2020 Aug 28.
Although belemnite rostra can be quite abundant in Jurassic and Cretaceous strata, the record of belemnite jaws was limited to a few specimens from Germany and Russia. Here, we describe and figure three cephalopod jaws from the Middle Jurassic Opalinus Clay of northern Switzerland. Although flattened, the carbonaceous fossils display enough morphological information to rule out an ammonoid, nautiloid or octobrachian origin of the two larger jaws. Their similarities to belemnite jaws from Germany and Russia conforms with our interpretation of these specimens as belemnite jaws. Based on their rather large size, we tentatively assign these two jaws to the megateuthidid . The third jaw is a rather small upper jaw of an ammonoid. Since is by far the most common ammonite in this unit in northern Switzerland, we tentatively suggest that the upper jaw belongs to this species.
虽然箭石吻部在侏罗纪和白垩纪地层中可能相当丰富，但箭石颚的记录仅限于来自德国和俄罗斯的少数标本。在此，我们描述并展示了来自瑞士北部中侏罗世富硅质泥岩的三个头足类颚。尽管这些碳质化石已被压扁，但仍显示出足够的形态学信息，以排除两个较大颚来自菊石、鹦鹉螺或八腕目的可能性。它们与来自德国和俄罗斯的箭石颚的相似性，使我们将这些标本解释为箭石颚。基于它们相当大的尺寸，我们初步将这两个颚归为巨型柔鱼科。第三个颚是一个相当小的菊石上颚。由于 是瑞士北部该地层中迄今为止最常见的菊石，我们初步认为这个上颚属于该物种。
