# Psittacosaurus mongoliensis

> The "parrot lizard", a small two-legged early horned dinosaur from the Early Cretaceous of Mongolia with a deep, beaked skull. Its genus is known from hundreds of skeletons, and one specimen kept skin, colour and bristles on its tail.

- Classification: Dinosauria (clade) > Ornithischia (clade) > Ceratopsia (clade) > Psittacosaurus (genus) > Psittacosaurus mongoliensis (species)
- Length: 2 m
- Hip height: 0.5–0.6 m
- Age: 143.1–100.5 million years ago (Early Cretaceous)
- Fossils found in: Öösh Formation (Övörkhangai Province); Mongolia
- Diet: herbivore
- Described: Henry Fairfield Osborn, 1923

Canonical page: https://dinodex.club/dinosaurs/psittacosaurus-mongoliensis
Last updated: 2026-09-27

## Overview

Psittacosaurus mongoliensis lived in the Early Cretaceous in what is now Mongolia. During the American Museum's Central Asiatic Expedition of 1922, the expedition's driver, Wong, found a nearly complete skeleton at Red Mesa, Artsa Bogdo, in the Oshih Basin, and Henry Fairfield Osborn named it in 1923 for its parrot-like beak.

It was one of the earliest ceratopsians, a distant relative of Triceratops without horns or a large frill, with a short, deep skull, a strong beak and small bony cheek bosses. Adults walked on two legs, and the largest P. mongoliensis reached about 2 m.

Psittacosaurus is the most species-rich non-avian dinosaur genus and one of the best known, with growth series from hatchlings to adults. A Chinese Psittacosaurus specimen preserves long bristles on the tail (Mayr et al. 2002) and a countershaded skin pattern suggesting it lived in forests (Vinther et al. 2016).

## Name meaning

"Parrot lizard", from Greek psittakos and sauros, for its beak; mongoliensis for Mongolia (Osborn 1923).

## Sources

1. (2026). Paleobiology Database: Psittacosaurus mongoliensis type collection 48936. The Paleobiology Database (paleobiodb.org), data service 1.2, accessed 2026-09-23. https://paleobiodb.org/data1.2/colls/list.json?coll_id=48936&show=paleoloc,strat,loc,ref,geo&pgm=gplates&vocab=pbdb
2. (2026). Wikipedia: Psittacosaurus. Wikipedia (English), accessed 2026-09-24. https://en.wikipedia.org/wiki/Psittacosaurus
3. Mayr, G., Peters, D. S., Plodowski, G. & Vogel, O. (2002). Bristle-like integumentary structures at the tail of the horned dinosaur Psittacosaurus. Naturwissenschaften 89: 361-365. https://doi.org/10.1007/s00114-002-0339-6
4. Osborn, H. F. (1923). Two Lower Cretaceous dinosaurs of Mongolia. American Museum Novitates 95: 1-10.
5. Paul, G. S. (2016). The Princeton Field Guide to Dinosaurs (2nd edition). Princeton University Press.
6. Vinther, J., Nicholls, R., Lautenschlager, S., Pittman, M., Kaye, T. G., Rayfield, E., Mayr, G. & Cuthill, I. C. (2016). 3D camouflage in an ornithischian dinosaur. Current Biology 26: 2456-2462. https://doi.org/10.1016/j.cub.2016.06.065

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Cite as: "Psittacosaurus mongoliensis". DinoDex. https://dinodex.club/dinosaurs/psittacosaurus-mongoliensis (updated 2026-09-27).