''Biltnerites'' is a genus of

ammonite Ammonoids are a group of extinct marine mollusc animals in the subclass Ammonoidea of the class Cephalopoda. These molluscs, commonly referred to as ammonites, are more closely related to living coleoids (i.e., octopuses, squid and cuttlefish) ...

s (''

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'') from the lower Triassic included in the ceratitacean family Tirolitidae of the order Ceratitida, characterized by a flat, evolute shell with moderately compressed, rounded whorls. The spinose stage characteristic of the Tirolitidae is absent, but the outer whorl does have indistinct ribs that cross the venter. ''Biltnerites'' has been found in

Lower Triassic The Early Triassic is the first of three epochs of the Triassic Period of the geologic timescale. It spans the time between Ma and Ma (million years ago). Rocks from this epoch are collectively known as the Lower Triassic Series, which is a un ...

sediments is S.E. Europe

References

Treatise on Invertebrate Paleontology The ''Treatise on Invertebrate Paleontology'' (or ''TIP'') published by the Geological Society of America and the University of Kansas Press, is a definitive multi-authored work of some 50 volumes, written by more than 300 paleontologists, and co ...

, Part L; Ch. Mesozoic Ammonoidea. Geological Soc of America and U Kansas Press, R.C Moore (ed) Ceratitoidea Ceratitida genera Triassic ammonites Ammonites of Europe {{Ceratitida-stub