Keywords: Asaphus expansus robustus.JPG en Asaphus expansus robustus Ivantsov 2003; Paleozoic Middle Ordovician Kunda Horizon Darriwilian Stage 468 - 460 MA Lava River Saint Petersburg Russia own Tomleetaiwan 2009-07-04 Asaphus Asaphida fossils Darriwilian fossils Middle Ordovician fossils from Russia |