Какова степень их описанности? 
"Gnilovskaya (1998) published a description of the new genus Parmia, increasing the diversity of worm-like forms inhabiting the ocean during the Late Riphean, significantly older than the Ediacara faunas. More than 80 specimens of Parmia were recovered from a borehole core drilled in southern Timan, on the northeastern Russian Platform. With a maximum length up to 60 mm and a body width up to 2.5 mm, these organisms have regular segmentation (7-11 segments per millimeter of body length). Parmia is interpreted as a probable predecessor of annelid worms. All geological and paleontological evidence (including the associated microfossil assemblage) indicates Parmia lived about 1 billion years ago (Gnilovskaya et al., 2000). Although the exact age of Sinosabellidites
(зверь из Китая, представитель т.н. хуайнаньской биоты (см. напр. К.Еськов - История земли и жизни на ней) - Ю.) and Parmia is yet to be determined with certainly, these metazoan fossils are without doubt decidently older than the Ediacara-type metazoans known from the late Neoproterozoic."
Fedonkin M.A. et al. 2007. The rise of animals: evolution and diversification of the kingdom animalia.
http://books.google.ru/books?id=KsFFIrJ8IxEC&pgСсылки:
Gnilovskaya, M. B., 1998: The oldest annelidomorphs from the Upper Riphean of Timan. Doklady Akademii Nauk, vol. 359, p. 369-372. (In Russian and English)
Gnilovskaya, MB., Becker, Yu. R., Weiss. A. F., Olovyanishnikov Vs. G. and Raaben, M. E., 2000: Pre-Ediacaran fauna of Timan (Upper Riphean annelidomorphs). Stratigraphy. Geological Correlation, vol. 8, no. 4, p. 11-39.
Fedonkin M.A., 2003: The origin of the Metazoa in the light of the Proterozoic fossil record. Paleontological Research, vol. 7, no. 1, pp. 9-41.
