![]() In addition to the upper and lower jaw, it preserves the fractured phragmocone, a patch with ink, and a patch with many arm hooks, some of which are still aligned with the respective arm. This specimen (SMNS 67335) was assigned to Hibolithes, the most common species in these strata. The first belemnite jaws revealing some more morphological information come from the Kimmeridgian of Nusplingen, Germany (for stratigraphic and locality details, see Klug et al. Jaws remains were first recognized by Reitner and Urlichs ( 1983), but their specimens only showed black patches near the bases of the arms, which lack morphological detail. Fossilized body parts include, in descending order according to the abundance of their preservation, remains of the phragmocone, arm hooks, remains of the mantle musculature, ink sac, proostracum and jaws. All other body parts are much less commonly preserved and true belemnite soft parts were not described before 1983 (Reitner and Urlichs 1983), after a series of fakes had been erroneously published as first records of belemnite soft parts (Huxley 1864 Wiesenauer 1976 Rietschel 1977 Seilacher and Wiesenauer 1978). In contrast to other hard parts, the low magnesium calcite rostra of belemnites represent abundant fossils in the Jurassic and Cretaceous, sometimes occurring in rock-forming numbers (Doyle and Macdonald 1993 Rita et al. 2016 Donovan & Fuchs 2016 Klug and Tajika 2018 Wani et al. 2010a, b, 2016 Keupp and Mitta 2015 Clements et al. 2002, 2003 Weis and Delsate 2006 Klug and Fuchs 2010 Klug et al. With the ten-armed coleoids, the decabrachians, they share an internal skeleton largely surrounded by a muscular mantle, a large brain compared to other invertebrates, ten arms, chitinous jaws, large lateral eyes, and a predatory mode of life (e.g., Naef 1922 Reitner and Urlichs 1983 Doguzhaeva et al. Belemnites are extinct coleoid cephalopods, i.e., relatives of modern squids, cuttlefishes and octopuses (Fuchs 2006 Kröger et al.
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