Variation in rates of decay and disarticulation of Echinodermata; implications for the application of actualistic data

Actualistic laboratory experiments have documented the preservation potential of selected echinoderms and have calibrated rate of decay with weight-loss of chitin in litter bags. The results are integrated with field experiments which quantified decay rate in flowing seawater, intertidal sediments and freshwater mud using identical litter bags. Decay rate of chitin was generally slower in freshwater sediments than in marine muddy environments and open seawater. Sediment-induced variation in decay rate is within an order of magnitude. The duration of decay required to promote fragmentation varied little between the two regular echinoids but differed by an order of magnitude between the holothurians