Exceptional preservation of internal organs in a new fossil species of freshwater shrimp (Caridea: Palaemonoidea) from the Eocene of Messel (Germany)

Researchers have uncovered a new species of extinct freshwater shrimp, Bechleja brevirostris, from the Eocene deposits of Messel Pit in Germany. This rare discovery is notable for its exceptional preservation of soft tissues and internal organs, including the stomach, branchiae (gills), ovary, and mandible—structures never before documented in fossilized shrimp. The species is characterized by a short rostrum with 6-8 dorsal spines and one ventral tooth, along with elongated second pereiopods featuring strong chelae. One additional specimen exhibits slight morphological differences, suggesting it may represent another species. The study also delves into the systematic position of Bechleja brevirostris within the Palaemonoidea superfamily and its implications for reconstructing the paleoenvironment of Lake Messel during the Eocene epoch. This finding enhances our understanding of both the paleobiogeography and ecological dynamics of this UNESCO World Heritage Site.

de Mazancourt, V., Wappler, T., & Wedmann, S. (2022). Exceptional preservation of internal organs in a new fossil species of freshwater shrimp (Caridea: Palaemonoidea) from the Eocene of Messel (Germany). Scientific Reports, 12(1). https://doi.org/10.1038/s41598-022-23125-9