The microbial shift during the decomposition of Cambarellus diminutus in lake-water and – sediment under different environmental conditions. The microbial impact on the decomposition of Cambarellus diminutus

During the decomposition of crustaceans, a precipitation of calcite or aragonite crystal clusters precipitate composed out of calcite or aragonite were detected in several taphonomic experiments, up toresulting in the transformation mineralisation of organic tissue (e.g. muscles, digestive gland) into calcite or apatite . This mineralisation process, which might lead to the fossilisation of soft tissue and especially Tthe influence role of bacterial activity in these decay and mineralisation processes is something like an unknown “black box”is not well defined. This study Here, controlled taphonomic experiments were performed to is the first experimental approach that analyses the shifts in bacterial community composition in correlation to the different stages of decay and preservation, using 16S-rRNA amplicon analysisand the decay or preservation patterns in controlled taphonomic experiments with 16S-rRNA amplicon analysis. Precipitated minerals were analysed by µ-CT observation, SEM and Raman spectroscopy. Three dominating genera; , Aeromonas, Clostridium and Acetobacteroides, could bewere identified as the main drivers in the decomposition of crayfish in our freshwater experiments. Proteocatella sphenisci as the only known representative species of the genus Proteocatella, seems to play an important role in mineral precipitation. Using µ-CT measurements and scanning electron microscopy, crystal clusters were detected after three to four days and were identified as calcite by Raman spectroscopy. The presence of the genus Proteocatella was correlated with a stronger mineral precipitation.Precipitated minerals were analysed by µ-CT observation, SEM and Raman spectroscopy.