About Annularia spinalosa
Annularia spinalosa is an extinct species of ancient horsetail plant and closely related to the ones of today. Apparently these tree-like plants could grow to about 50 meters in height. Annularia is the name given to the leaves of a Calamites tree-like plant. The leaves of this species are small , very thin and long. They can be preserved in a few different colours ranging from yellow, orange and silver.
Age and Distribution
Calamites thrived during the Carboniferous as it is found almost everywhere in the world, during this time the Earth was a lot warmer and experienced almost no seasons (it was mostly a tropical enviroment). So it was ideal for plants. This specimen was found near Osnabrück in Germany. Where an old volcano burst through the crust a long time ago and took many of the top layers with it. After it eroded away it left the Carboniferous exposed. At that time this region was home to a series of lakes and rivers. From time to time a flash flood would occur and take everything with it. That is why the rocks are stuffed with fossils and not (finely) layered. Other flora and fauna that lived at this location were the plants Calamites, Asterophyllites equisetiformis, Neuropteris attenuata and many more. One could also encounter small horseshoe crabs here like the Euproops bifidus and many insects like dragonflies.
About the Equisetales Annularia spinalosa
During the Carboniferous a lot of plants became fossilized and were turned over time into fossil fuels, which we use today. The Osnabrück quarry still gets mined for that same reason, although they do keep certain sections available for research. Earliest found sphenophyllum date back from the late Devonian period. The Calamites was a very succesful plant during Carboniferous but dwindled and became extinct in the late Perm(no specimens from after this time have been found).
Annularia spinalosa belongs to the Calamitaceae which is a subclass of the Equisetales. There are at least 20+ species known and most are from the Carboniferous.