Noripterus

Noripterus
Temporal range: Early Cretaceous
Artist's impression, with Dsungaripterus weii (top)
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Pterosauria
Suborder: Pterodactyloidea
Superfamily: Dsungaripteroidea
Family: Dsungaripteridae
Genus: Noripterus
Young, 1973
Species
  • N. complicidens Young, 1973
Synonyms
  • Phobetor Bakhurina, 1982

Noripterus (meaning "lake wing" from Mongolian nuur, "lake" and Greek pteron, "wing") is a genus of dsungaripterid pterodactyloid pterosaur from Lower Cretaceous-age Lianmuqin Formation in the Junggar Basin of Xinjiang, China. It was first named by Yang Zhongjian (also known as C.C. Young in older sources) in 1973. Additional fossil remains have been recovered from Tsagaantsav Svita, Mongolia.

Contents

Description

The first, holotype specimen of Noripterus (IVPP V.4062, type locality IVPP 64045) preserved the front part of the skull and lower jaws, vertebrae, and partial limbs and pelvis. Noripterus was quite similar to the contemporaneous Dsungaripterus, though it was estimated to be a third shorter. It has long narrow neck vertebrae and, like Dsungaripterus, a crest and no teeth in the front of the lower jaw. The teeth that are present are well-developed and spaced fairly far apart. The sharp snout is straight and not pointed upwards as with Dsungaripterus.[1]

Classification

Because of its similarity to Dsungaripterus, Noripterus has been assigned to the family Dsungaripteridae.[2]

The genus Phobetor, named after the Greek god of nightmares, was in 1982 originally described by Natasha Bakhurina as a species of Dsungaripterus (D. parvus), based on a single lower leg bone, PIN 3953. The discovery of more remains later, among which an almost complete skull, GIN 100/31, was reason for Bakhurina to name D. parvus in 1986 as a separate genus, and the species name became Phobetor parvus. However, the genus name Phobetor was already being used as a junior synonym of a species of sculpin, namely, the arctic staghorn sculpin, Gymnocanthus tricuspis (synonym "Phobetor tricuspis" Krøyer, 1844) and thus unavailable. In 2009, Lü and colleagues re-examined much of the known dsungaripterid fossil material, and found that "Phobetor" was indistinguishable from Noripterus, causing them to refer to it as a junior synonym.[3]

Assigning the "Phobetor" material to Noripterus increases the known size of the latter as it indicates a maximum wingspan of four metres.[4]

Paleobiology and ecology

Dsungaripterids like Noripterus are interpreted as adapted for feeding on fish and shellfish, with long narrow toothless beak tips for probing for and picking up suitable prey, and robust teeth farther back for cracking shells. The skulls of these animals are more robust than those of other pterosaurs, as well as their limbs and vertebrae.[5]

Noripterus lived in the same time and place as the larger Dsungaripterus, in formations that indicate the presence of extensive inland lake systems. Because Noripterus had a more lightly built skull with weaker, more slender teeth than its larger contemporary, it is likely that the two pterosaurs occupied separate ecological niches, with Dsungaripterus hunting in the shallow parts of lakes and eating hard-shelled animals, while Noripterus fed on fish from deeper regions of the lakes.[3]

References

  1. ^ Yang, Zhongjian (1973). "Reports of Paleontological Expedition to Sinkiang (II): Pterosaurian Fauna from Wuerho, Sinkiang" (in Chinese). Memoirs of the Institute of Vertebrate Paleontology and Paleoanthropology Academia Sinica 11: 18–35. 
  2. ^ Unwin, David M. (2003) "On the phylogeny and evolutionary history of pterosaurs", in Evolution and Palaeobiology of Pterosaurs, 139-190.
  3. ^ a b Lü, J., Azuma, Y., Dong, Z., Barsbold, R., Kobayashi, Y., and Lee, Y.-N. (2009), "New material of dsungaripterid pterosaurs (Pterosauria: Pterodactyloidea) from western Mongolia and its palaeoecological implications." Geological Magazine, 146(5): 690-700.
  4. ^ D.M. Unwin & N.N. Bakhurina (2003), "Pterosaurs from Russia, Middle Asia and Mongolia", p. 426 In: Michael J. Benton e.a. (ed.), The Age of Dinosaurs in Russia and Mongolia, Cambridge University Press
  5. ^ Unwin, David M. (2006). The Pterosaurs: From Deep Time. New York: Pi Press. p. 273. ISBN ISBN 0-13-146308-X.