Saarina
| Saarina | |
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| A fossil of Saarina juliae | |
| Scientific classification | |
| Kingdom: | |
| Phylum: | |
| Family: | Saarinidae Sokolov, 1965
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| Genus: | Saarina Sokolov, 1965
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| Species | |
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Saarina are tube fossils from the Ediacaran (Vendian) and Early Cambrian marine deposites of the European Russia. These fossils are comparable to the dwelling tubes of worms or cnidarians.
Occurrence
Fossils of the type species, S. tenera, were found in a core from the Gatchina No.13 borehole in the Leningrad Region, Russia. The most conspicuous deposits associated with these fossils are referred to as the Lomonosov Fm., Lontova Horizon, and lower Tommotian (=Cambrian Stage 2).
S. kirsanovi fossils were found in core from the Vorob'evo No.1 borehole, Moscow Region and in core from the Malinovka borehole, near Obozersky in the Arkhangelsk Region.
S. juliae was found in core from the Gavrilov-Yam No.5 borehole, Yaroslavl Region. The deposites with S. kirsanovi and S. juliae are referred to the Redkino Horizon, Upper Vendian (Ediacaran), and aged about 558 mya.
Description
Saarina was a tube-dwelling organism of unknown biological affinity, known from its siliciclastic deposits dating to the late Ediacaran (Vendian) and lowest Cambrian of the Russian Platform. It was funnel-shaped, consisting of dense, thinly-walled and annulated, ringlike segments. The fossils are preserved in the substrate as a result of superficial mineralization at early stages of decomposition.
The fossils are typically found in mudstone and preserved in the form of flat pyrite ribbons as a result of superficial pyritization on early stage of organic decomposition.
Saarina tubes were cylindrical in form, conical at the base, consisting of funnel-shaped narrow rings. The wall of the tube was thin, originally organic-walled, not chitinous. The tubes attained widths up to 7 mm.
The species of the Saarina differ mainly in the forms of the funnels:
- S. tenera have a straight conical funnels.
- S. juliae have a conical funnels, curved outward.
- S. kirsanovi have a funnels curved inward.
See also
References
- Gnilovskaya, M. B. (1996). "New saarinids from the Vendian of the Russian Platform". Dokl. Ross. Akad. Nauk. 348: 89–93.