Enigmatic Margaretia: Putative Alga from Cambrian Utah

Description: The first fossils of multicellular green algae appear in the Cambrian strata of the early Paleozoic Era.. Complete algal fossils, identified as Yuknessia simplex and Margaretia dorus have been found in the Burgess shale of Canada; both genera have been classified as Chlorophytes, a distinct branch of green algae from the Streptophytes that eventually gave rise to the land plants. This taxon has not been well studied.

The assignment as an alga is not totally secure; it also resembles some corals, a position held by C.D. Walcott, the discoverer of the Burgess Shale early last century. Most researchers currently ascribe to the assignment as an alga.

Reference: The Fossils of the Burgess Shale by D. E. Briggs, et al