Describer

Sereno, Zhao, Brown and Tan 2007

Time

Cretaceous Early Berriasian Valanginian

Classification

Ornithischia Genasauria Cerapoda Marginocephalia Ceratopia Neoceratopia Psittacosauridae

Diet

Herbivore

Fossilsite

Yixian Formation, Liaoning Province, China

Fall Under

Psittacosaurus

Info

Psittacosaurus (Osborn, 1923) = Protiguanodon (Osborn, 1923)
Psittacosaurus > Psittacosaurus guyangensis (Cheng, 1983)
Psittacosaurus > Psittacosaurus mongoliensis (Osborn, 1923) = Psittacosaurus protiguanodonensis (Young, 1958) > Protiguanodon mongoliensis (Osborn, 1923)
Psittacosaurus > Psittacosaurus osborni (Young, 1931) > Psittacosaurus tingi (Young, 1931)
Psittacosaurus > Psittacosaurus sinensis (Young, 1958) > > Psittacosaurus youngi (Chao, 1962)
Psittacosaurus > Psittacosaurus meileyingensis (Sereno, Chao, Cheng & Rao, 1988)
Psittacosaurus > Psittacosaurus xinjiangensis (Sereno & Chao, 1988)
Psittacosaurus > Psittacosaurus neimongoliensis (Russell & Zhao, 1996)
Psittacosaurus > Psittacosaurus mazongshanensis (Dong & Azuma, 1996)
Psittacosaurus > Psittacosaurus ordosensis (Russell & Zhao, 1996)
Psittacosaurus > Psittacosaurus lujiatunensis (Zhou, Gao, Fox, and Chen, 2006)
Psittacosaurus > Psittacosaurus sibiricus (Averianov, Voronkevich, Leshchinskiy, Fayngertz, 2006)
Psittacosaurus > Psittacosaurus major (Sereno, Zhao, Brown and Tan 2007)
Psittacosaurus> Psittacosaurus gobiensis (Sereno, Zhao & Tan 2010)

Holotype

LH PV1, articulated skull and nearly complete postcranial skeleton. The skull is nearly complete lacking only the right, and most of the left, palpebral, and portions of the right postorbital and squamosal. The postcranial skeleton lacks the left pubis, right radius and portions of the right manus, left tibia and fibula, and portions of the left pes.

Etymology

From the Latin, major, meaning greater.

Diagnosis

Psittacosaurid with a large skull relative to its postcranial skeleton (30% larger than Psittacosaurus mongoliensis and most other species); transversely narrow dorsal skull roof as a result of the narrowest proportions of the nasals and frontals among psittacosaur species; the most prominent dentary flanges of any psittacosaur species with a depth approximately one−third that of the mandibular ramus; ventrolaterally projecting jugal horn; absence (closure) of the external mandibular fenestra as in Psittacosaurus sinensis and Psittacosaurus neimongoliensis; seven sacral vertebrae (one dorsosacral added with rib attachment to the distal end of the preacetabular process), one more than in other psittacosaur species.