Duration of several early eukaryotic fossils without obvious morphological change

Range Trachyhystrichosphaera ~400: Tappania ≥600: Chuaria ⁄ Tawuia ~1000: Valeria >1100 million years
Organism Eukaryotes
Reference Butterfield NJ, Macroevolution and macroecology through deep time, Paleontology, Volume 50, Issue 1 January 2007 Pages 41–55, DOI: 10.1111/j.1475-4983.2006.00613.x link p.44 left column bottom paragraph
Primary Source See link
Comments P.43 right column 2nd paragraph: "Distinctively spinose Trachyhystrichosphaera, for example, ranges for some 400 myr without obvious morphological change, while Tappania persists for at least 600 myr (primary source Butterfield 2005a), Chuaria⁄Tawuia macrofossils for c. 1000 myr (primary sources Kumar 2001, Butterfield 2004), and concentrically sculptured Valeria for over 1100 myr (primary sources Hofmann 1999, Knoll et al. 2006). Not surprisingly, the pre-Ediacaran acritarch record has yet to yield any useful patterns of biostratigraphic zonation (or indeed any biogeographical partitioning, see below)."
Entered by Uri M
ID 113589