Permian of Russia In this somewhat dry setting near a lake, there is a group of Araucaria trees and in the middle distance some proto-gymnosperm trees (noeggerathialian). There are also some cycads and equisetums. A pair of Dimedrodons (Synapsids) bask in the sun. In the extreme foreground resting on the growing tip of a horsetail (equisetum) is a caloneurodean (Paleuthygramma tenuicornis, Paleuthygrammatidae) (these grew to 24mm). Below left, resting on a rock there is a small arachnid of the Order: Uraraneida. These spiders had a tail (flagellum). Flying above is another insect Sylvohymen sibericus. (order: Megasecoptera).