Pywackia is a contentious Cambrian fossil that has been interpreted as the earliest (total group) Bryozoan, and the only representative of that phylum in the Cambrian period.

[1] Its Bryozoan credentials have been called into question,[2] but the octocoral alternative is equally unconvincing, and there are reasons to suggest a position in the Stenolaemata stem lineage.

[3] Finally, the skeletal microstructure is consistent with a cnidarian affinity, but insufficient to support a close affinity with any modern subgroup.

[4]