Taxonomy of commonly fossilised invertebrates

Although the phylogenetic classification of non-vertebrate animals (both extinct and extant) remains a work-in-progress, the following taxonomy attempts to be useful by combining both traditional (old) and new (21st-century) paleozoological terminology.

The paleobiologic systematics which follows is not intended to be all-inclusive or completely comprehensive. For practical reasons and relevancy, the below classification and annotations emphasize invertebrates that (a) are popularly collected as fossils and/or (b) no longer continue alive on this planet. Therefore, as a result, some phyla, classes, and orders of invertebrates are not listed.

If a non-vertebrate animal is mentioned below using its common, or vernacular name, the creature is usually a living, present-day invertebrate. But if a non-vertebrate is cited below by its scientific, taxonomic genus (in italics), then it is typically an extinct invertebrate, known only from the fossil record.

Invertebrate clades that are (a) very important as fossils (for example, ostracods frequently used as index fossils), and/or (b) very abundant as fossils (for example, crinoids easily found in crinoidal limestone), are highlighted with a bracketed exclamation mark [ ! ].

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