''Pywackia'' is a contentious

Cambrian The Cambrian Period ( ; sometimes symbolized Ꞓ) was the first geological period of the Paleozoic Era, and of the Phanerozoic Eon. The Cambrian lasted 53.4 million years from the end of the preceding Ediacaran Period 538.8 million years ag ...

fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

that has been interpreted as the earliest ( total group) Bryozoan, and the only representative of that

phylum In biology, a phylum (; plural: phyla) is a level of classification or taxonomic rank below kingdom and above class. Traditionally, in botany the term division has been used instead of phylum, although the International Code of Nomenclatu ...

in the Cambrian period. Its Bryozoan credentials have been called into question, but the octocoral alternative is equally unconvincing, and there are reasons to suggest a position in the Stenolaemata stem lineage.

References

{{Taxonbar, from=Q20817953 Fossils of Mexico Enigmatic prehistoric animal genera Cambrian invertebrates Cambrian fossil record Fossil taxa described in 2010 Cambrian genus extinctions