Shuranoceras
Shuranoceras is a genus in the extinct oncocerid family Karoceratidae that plied the shallow sea floor from the Early Silurian to the Early Devonian. "Shuranoceras" is characterized by a smooth, compressed, slowly enlarging orthoconic shellwith a ventral submarginal siphuncle composed of complex segments. "Shuranoceras" was found in middle Silurian strata in Ferghana, central Asia. Oncocerids (Order Oncocerida) were Nautiloid cephalopods that lived during the early part of the Paleozoic Era. They are closely related to the Nautilids that include the living "Nautilus", but on a different evolutionary branch