Calcified rock-forming marine filamented benthic micro- and macrophytes of Dzhelindia Kolosov, 1970 (Figure 1(а)) and Chaptchaica Kolosov, 1975 (Figure 1(b)) genera, thrived in Neoproterozoic (1000-541 million years ago) Siberia together with cyanobacteria. Their belonging to Rhodophyta is well-grounded. These and other Neoproterozoic rodofits, as well as Epiphyton Bornemann 1886 (Figure 1(c)) and other Early Cambrian (541-513 million years ago) benthic algae, oxygenating floor of epicontinental sea basin, formed conditions, favorable for the animals. In combination with other biotic, and such abiotic factors as: equatorial position and tectonic feature of Siberian platform; volcanism; transgression of the sea; diversity of ecologic niches, these conditions were prerequisites of skeleton and shell acquisition by Early Cambrian animals, and as a consequence, accelerated morphologic evolution, increased diversity of taxons of different groups of animals.
 A. H. Knoll, “Proterozoic and Early Cambrian Protists: Evidence for Accelerating Evolutionary Tempo (Proterozoic/Cambrian/Eukaryotes),”Proceedings of the National Academy of Sciences, Vol. 91, No. 15, 1994, pp. 6743-6750.
 P. N. Kolosov, “Upper Precambrian Organic Remains of the Southern Yakutia,” In: A. K. Bobrov, Ed., Proterozoic and Cambrian Stratigraphy and Paleontology of the East Siberian Platform, Book Publisher, Yakutsk, 1970, pp. 57-70.
 J. L. Kirschvink and A. Yu. Rozanov, “Magnetostratigraphy of Lower Cambrian State from the Siberian Platform: A Paleomagnetic Pole and a Preliminary Polarity Time-Scale,” Geological Magazine, Vol. 121, No. 4, 1984, pp. 189-203.