Lancian

The Lancian was a North American faunal stage of the Late Cretaceous.

Terrestrial sedimentary strata from the Judithian to the Lancian are generally regressive throughout the entire sequence, so the preserved changes in fossil communities represent not only phylogenetic changes but ecological zones from the submontane habitats to near-sea level coastal habitats.

By the Lancian, the crested hadrosaurs are no longer the dominant inhabitant of any province of western North America; with the exception of Hypacrosaurus. Lehman records three surviving chasmosaurs, Triceratops, Torosaurus and Nedoceratops, with the possibility of the recently discovered Ojoceratops, Regaliceratops and Bravoceratops. It has recently been suggested that Triceratops and Torosaurus may be synonymous, though this is still up for debate. Saurolophine dinosaurs like Edmontosaurus, Kritosaurus, Saurolophus as well as the recently discovered Augustynolophus were some of the known surviving hadrosaurs. Both lack the elaborate ornamentation of their predecessors, the lambeosaurs. The ankylosaurs had been reduced to down to a few species, ankylosaurs like Anodontosaurus and Ankylosaurus, as well as nodosaurs like Denversaurus, Edmontonia and Glyptodontopelta were the only known survivors. In the south the transition to the Lancian is even more dramatic, which Lehman describes as "the abrupt reemergence of a fauna with a superficially "Jurassic" aspect." These faunas are dominated by Alamosaurus and feature abundant Quetzalcoatlus, Bravoceratops and Ojoceratops in Texas.

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