In 2008, a new basal neoceratopsian was discovered in the Tando beds (Albian) of Tando Basin in South Korea. It represents
the first ceratopsian dinosaur in the Korean peninsula and is assigned to Koreaceratops hwaseongensis gen. et sp. nov. Autapomorphies of Koreaceratops include very tall neural spines over five times higher than the associated centra in the distal caudals, and a unique astragalus
divided into two fossae by a prominent craniocaudal ridge on the proximal surface. A phylogenetic analysis indicates that
Koreaceratops is positioned between Archaeoceratops and all more derived neoceratopsians, and the elongation of caudal neural spines was an important derived character in non-ceratopsid
neoceratopsians. The very tall caudal neural spines in Koreaceratops, Montanoceratops, Udanoceratops, Protoceratops, and Bagaceratops appear to be homoplasious, suggesting an independent adaptation, possibly for swimming. Skeletal evidence suggests that obligate
quadrupedalism occurred gradually in neoceratopsians progressing from bipedal through facultative quadrupedalism, to complete
quadrupedalism in Coronosauria.
Keywords Basal neoceratopsian –
Koreaceratops hwaseongensis
– Tando beds – Late Early Cretaceous – Hwaseong City – South Korea
Communicated by Robert Reisz