Marocella: Antarctic specimens of an enigmatic Cambrian animal
Remarkably well-preserved specimens of Marocella Geyer, 1986, from the Lower Cambrian Shackleton Limestone of Antarctica show that although affinity with chondrophorine cnidarians is improbable, its rigid caplike shell also is unlike that of any known mollusk. Association with sclerite-bearing taxa cannot be ruled out, but at present the phylogenetic affiliation of the genus remains equivocal.
Evans, K. R. "Marocella: Antarctic specimens of an enigmatic Cambrian animal." Journal of Paleontology (1992): 558-562.
Journal of Paleontology