Wavy Cryptozoan rosemontensis Ordovician Stromatolites

Coming from the Lower Ordovician Oneota Formation, it is some 495 million years old, from a time that Prokaryotic life forms no longer had exclusive use of earth's shorelines. Concomitantly, the earths coastal habitats had markedly reduced stromatolite reafs, compared with the Proterozoic.

By this time in geological history, microbial communities consisted of complex consortia of both prokaryotic and eukaryotic forms with diverse metabolic needs, and competition for resources and differing motility among them made for an intriguing microcosm of interacting life, some autotrophic, some chemotrophic and some heterotrophic.

This particular specimen has been cut horzontally thus revealing wavy laminae. Note how the fine hand polishing reveals the stromatolitic growth history in a beautiful form.