Charnia is a highly significant fossil because it is the first fossil which was ever described to have come from undoubted Precambrian rocks. Prior to 1958, the Precambrian was thought to be completely devoid of fossils and consequently possibly devoid of macroscopic life.
Source :Wikipedia
Because of their appearance, the organisms were originally thought to be a type of plant, but subsequent analyses suggest that they lived in very deep waters where there would have been insufficient light.
Another hypothesis was that Charnia was a type of 'Sea Pen' - species of which are still alive today - but this idea has now been discounted.
The organisms had no obvious feeding mechanism (gut etc.). How they survived, and to which species they might be related, is currently unknown.
Also see: Chitinozoaplugin-autotooltip__plain plugin-autotooltip_bigChitinozoa
Chitinozoans are bottle-shaped marine microfossils which thrived during the Ordovician, Silurian, and Devonian periods. They often have root-like structures at the base of the 'flask'. They were first described in 1931 by the German micropaleontologist Alfred Eisenack.