Definition: Active swimming organisms that live in the water column and are able to move independently of the water mass (adapted from Lincoln et al., 1998).
Definition: A habitat that is in or on a body of water containing low concentrations of dissolved salts and other total dissolved solids (<0.5 grams dissolved salts per litre).
Definition: A specialized form of biogenic tissue in which the extracellular matrix is mineralized, and which functions in mechanical and structural support.
Definition: A specialized form of biogenic tissue in which the extracellular matrix is mineralized, and which functions in mechanical and structural support.
Definition: A specialized form of biogenic tissue in which the extracellular matrix is mineralized, and which functions in mechanical and structural support.
Definition: A specialized form of biogenic tissue in which the extracellular matrix is mineralized, and which functions in mechanical and structural support.
Definition: A specialized form of biogenic tissue in which the extracellular matrix is mineralized, and which functions in mechanical and structural support.
Definition: The number of fossil occurrences in the Paleobiology Database (https://paleobiodb.org) that are identified as belonging to a particular taxon or any of its subtaxa.