Glossary

A **Lagerstätte** (plural Lagerstätten) is a sedimentary deposit that preserves an exceptionally high amount of paleontological information, either through the sheer abundance of fossils or through the extraordinary quality of their preservation. The concept was formalized in 1970 by German paleontologist Adolf Seilacher, who distinguished two primary categories. **Konzentrat-Lagerstätten** are concentration deposits where large numbers of fossils—typically disarticulated hard parts—accumulate at a single locality through mass mortality events, predator traps, or prolonged accumulation at hydrographic traps. **Konservat-Lagerstätten** are conservation deposits defined by exceptional preservation fidelity, frequently retaining non-biomineralized soft tissues such as integument, musculature, digestive tracts, nervous tissue, and feathers. The genesis of Konservat-Lagerstätten requires a precise confluence of conditions: rapid burial (obrution), anoxic or dysoxic pore-water chemistry, microbial sealing, fine-grained sediment, and specific early diagenetic mineralization pathways. Because this combination of factors is exceedingly rare, fewer than 700 Konservat-Lagerstätten have been documented worldwide. Lagerstätten are of paramount importance to paleobiology because they capture diversity, anatomy, and ecology invisible in the conventional fossil record, including entirely soft-bodied clades, internal organ systems, color patterns, and complete community structures that have fundamentally reshaped understanding of major evolutionary transitions.