Classifying vertebrate assemblages preserved in Quaternary tank deposits: Implications for vertebrate taphonomy and paleoecology

• I define a new terminology to classify Quaternary assemblages of tank deposits.
• Classification includes three groups of fossil vertebrate assemblages.
• These terminologies can also be applied to sinkhole, fissure and cave assemblages.
• Direct comparisons and accurate paleoecological interpretations are now possible.

Paleoecological interpretations require detailed taphonomic analyses which can reveal how fossil accumulations are related to the original site of life and death of organisms. In other words, only a taphonomic approach can unveil the quality of a fossil concentration and its potential for paleoecology. A frequent issue in vertebrate taphonomy and paleoecology is the definition of autochthony, parautochthony and allochthony. These terms are widely employed to translate the spatial quality of a fossil assemblage. However, its application in terrestrial vertebrate accumulations, especially in natural tank ones, is quite confused. This work proposes a form of classification of fossil vertebrate accumulations of natural tanks in relation to their proximity to the original place of death of the biocoenoses. The terms “autochthonous”, “parautochthonous” and “allochthonous”, originally defined based on the analysis of marine shelly faunas are reinterpreted in attempt to clarify their application to vertebrate assemblages preserved in natural tank deposits. This classification can also be applied to other trap assemblages, such as fissures, sinkholes and caves.