genus of reptiles (fossil)

Pinacosaurus ("plank lizard") is a genus of medium-sized ankylosaur dinosaurs from the Upper Cretaceous of Mongolia and China. It lived about 80–75 million years ago, and was first found in 1923.[1]

Temporal range: Upper Cretaceous, 80–75 mya
P. mephistocephalus
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Clade: Dinosauria
Order: Ornithischia
Clade: Thyreophora
Suborder: Ankylosauria
Family: Ankylosauridae
Subfamily: Ankylosaurinae
Genus: Pinacosaurus
Gilmore 1933
  • P. grangeri Gilmore, 1933 (type)
  • P.? mephistocephalus Godefroit et al., 1999
  • Pinacosaurus ninghsiensis
    Young, 1935
  • Heishansaurus pachycephalus?
    Bohlin, 1953
  • Syrmosaurus viminocaudus
    Maleev, 1952

Pinacosaurus had between two and five additional holes near each nostril, which have not been explained.

The animal was a medium-sized ankylosaur, about five metres long, weighing up to two tonnes. Its body was flat and low-slung but not as heavily built as in some other ankylosaurs.

Its head was protected by bone tiles, hence the name. A smooth beak bit off low-growing plants that were sliced up by rows of small teeth and then swallowed. Food was slowly processed by its enormous hind gut. Neck, back and tail were protected by osteoderms. The animal could also actively defend itself with its tail club.[2]

References change

  1. Gilmore C.W. 1933. Two new dinosaurian reptiles from Mongolia with notes on some fragmentary specimens. American Museum Novitates 679: 1–20.
  2. Hill R.V; Witmer L.W. & Norell M.A. 2003. A new specimen of Pinacosaurus grangeri (Dinosauria: Ornithischia) from the Late Cretaceous of Mongolia: ontogeny and phylogeny of Ankylosaurs. American Museum Novitates 3395: 1–29.