Anhanguera (pterosaur)

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search

Anhanguera
Temporal range: Albian
~112 Ma
Anhanguera blittersdorffi.png
A. blittersdorffi holotype skull (MN 4805-V)
Scientific classification e
Kingdom: Animalia
Phylum: Chordata
Order: Pterosauria
Suborder: Pterodactyloidea
Family: Anhangueridae
Genus: Anhanguera
Campos & Kellner 1985
Type species
Anhanguera blittersdorffi
Campos & Kellner 1985
Other species
Synonyms

"Pricesaurus" Martins-Neto, 1986 (nomen nudum)

Anhanguera (meaning "old devil") is a genus of pterodactyloid pterosaur known from the Early Cretaceous (Albian age, 112 Ma) Santana Formation of Brazil. This pterosaur is closely related to Ornithocheirus, and belongs in the family Ornithocheiridae within its own subfamily, Anhanguerinae.[1]

Description[edit]

Life restoration of A. blittersdorffi

Anhanguera was a fish-eating animal with a wingspan of about 4.6 metres (15 ft).[2] Like many other ornithocheirids, Anhanguera had rounded crests at front of its upper and lower jaws, which were filled with angled, conical but curved teeth of various sizes and orientations. Like many of its relatives, the jaws were tapered in width, but expanded into a broad, spoon-shaped rosette at the tip. It is distinguished from its relatives by subtle differences in the crest and teeth: unlike its close relatives Coloborhynchus and Ornithocheirus, the crest on the upper jaw of Anhanguera did not begin at the tip of the snout, but was set farther back on the skull. Like many ornithocheiroids, (most notably the pteranodonts but also in ornithocheirids such as Ludodactylus) Anhanguera had an additional crest protruding from the back of the skull. However, it was reduced to a small, blunt projection in these animals.[3]

Size of A. blittersdorffi compared to a human

A study in 2003 showed that Anhanguera held its head at an angle to the ground due to its inner ear structure, which helped the animal detect its balance.[4] Anhanguera had bony disks in their eye sockets, called sclerotic rings. These disks may have provided support to the pterosaur's eyes. Sclerotic rings are found in some extant species of vertebrates.[citation needed]

Classification[edit]

There are three species of Anhanguera: A. blittersdorfi, the type species; A. piscator; and A. spielbergi. A. blittersdorfi is based on a complete skull from the Romualdo Formation calcareous concretions (Santana Group) of the Ceará and Pernambuco states of Brazil.[1][2][3][5] The species A. piscator, known from a nearly-complete skeleton, was at one point proposed to belong to the genus Coloborhynchus,[6] but has more recently been placed back into Anhanguera by Andres and Myers.[7] Also known from a complete skeleton is A. spielbergi, which was also originally considered a species of Coloborhynchus.[8][9]

Below is a cladogram showing the phylogenetic placement of this genus within Pteranodontia from Andres and Myers (2013).[7]

Ornithocheirae

 Anhangueridae 


Liaoningopterus gui


Anhanguera


"Anhanguera araripensis"




Anhanguera blittersdorffi




Anhanguera piscator



"Anhanguera santanae"






 Ornithocheiridae 


Tropeognathus mesembrinus




Ornithocheirus simus




Coloborhynchus clavirostris



Coloborhynchus wadleighi






Invalid species[edit]

Anhanguerid skeleton AMNH 22555, which was formerly assigned to A. santanae

Various other species have been assigned to Anhanguera, but all of them are either dubious or have been transferred to other genera. A 2017 review found A. araripensis, A. robustus, and A. santanae to be based on non-diagnostic material, and therefore were dubious.[8]

  • ?A. araripensis[9] (Wellnhofer 1985) = Santanadactylus araripensis Wellnhofer 1985 [also classified as Coloborhynchus]
  • ?A. cuvieri (Bowerbanks 1851) = Ornithocheirus cuvieri = Pterodactylus cuvieri Bowerbank 1851 [now classified as Cimoliopterus]
  • ?A. fittoni (Owen 1858) = Pterodactylus fittoni Owen 1858
  • ?A. robustus (Wellnhofer 1987) = Tropeognathus robustus Wellnhofer 1987 [also classified as Coloborhynchus]
  • ?A. ligabuei (Dalla Vecchia 1993) = Cearadactylus ligabuei Dalla Vecchia 1993 [also classified as Coloborhynchus or Cearadactylus]
  • ?A. santanae (Wellnhofer 1985) = Araripesaurus santanae Wellnhofer 1985

Pricesaurus[edit]

Underside of A. blittersdorffi skull

In 1986, Rafael Gioia Martins-Neto reported the find of a pterosaur that he named "Pricesaurus megalodon" in a lecture during the 38th Reunião Anual da Sociedade Brasileira para o Progresso da Ciência at São Paulo. The abstracts of the congress were subsequently published that year in the magazine Ciência e Cultura. The generic name honours Llewellyn Ivor Price. The specific name is derived from Greek μέγας, megas, "large", and ὀδών, odon, "tooth".[10] The species was based on two syntypes that Martins-Neto considered to have originated from a single individual animal, even though he had separately acquired them from commercial fossil dealers in two nodules: specimen CPCA 3592, a 9 centimetres (3.5 in) long point of a snout, and specimen CPCA 3591, an 18 centimetres (7.1 in) long middle part of a skull. Pricesaurus is thus exclusively known from cranial material. Both specimens were probably found in the Romualdo Member of the Araripe Basin and both are part of the collection of the Centro de Pesquisas Paleontológicas da Chapada do Araripe.[10]

Martins-Neto provided a diagnosis of four distinctive traits: the breadth of the premaxillae; the closely positioned teeth; the deep premaxillary tooth sockets; and the rounded front of the fenestra nasoantorbitalis. However, in 1988 Alexander Kellner concluded that Pricesaurus was a nomen vanum, primarily because the specimens almost certainly represented different individuals. According to Kellner, the snout was from a larger animal than the middle part of the skull. In addition, the diagnosis did not contain true autapomorphies.[5]

In 2012, a publication by Felipe Lima Pinheiro and colleagues presented the first detailed study of the specimens. It was concluded that the fossils indeed came from different individuals, even though their size was not necessarily incompatible. The snout showed that the fifth and sixth tooth pairs are smaller than the fourth and seventh, making the specimen indistinguishable between Anhanguera blittersdorffi and Anhanguera piscator, which show the same tooth pattern. Both specimens were referred to as Anhanguera sp. Pinheiro et al. also stated that Pricesaurus is a nomen nudum because it was named in an abstract.[11]

See also[edit]

References[edit]

  1. ^ a b Campos, D. de A., and Kellner, A. W. (1985). "Un novo exemplar de Anhanguera blittersdorffi (Reptilia, Pterosauria) da formaçao Santana, Cretaceo Inferior do Nordeste do Brasil." In Congresso Brasileiro de Paleontologia, Rio de Janeiro, Resumos, p. 13.
  2. ^ a b Aureliano, T., Ghilardi, A. M., Duque, R. R., & Barreto, A. M. (2014). ON THE OCCURRENCE OF PTEROSAURIA IN EXU, PERNAMBUCO (LOWER CRETACEOUS ROMUALDO FORMATION, ARARIPE BASIN), NORTHEASTERN BRAZIL. Estudos Geológicos, 24(2), 15-27. Available in: "Archived copy" (PDF). Archived from the original (PDF) on 2016-11-20. Retrieved 2016-08-25. 
  3. ^ a b Kellner, A.W.A. and Tomida, Y. (2000). "Description of a new species of Anhangueridae (Pterodactyloidea) with comments on the pterosaurfauna from the Santana Formation (Aptian–Albian), northeastern Brazil." Tokyo, National Science Museum (National Science Museum Monographs, 17).
  4. ^ Witmer, L.M., Chatterjee, S., Franzosa, J. and Rowe, T. (2003). "Neuroanatomy of flying reptiles and implications for flight, posture and behaviour." Nature, 425(6961): 950-954. doi:10.1038/nature02048
  5. ^ a b Kellner A.W.A. & Campos D.A., 1988, "Sobre um novo pterossauro com crista sagital da Bacia do Araripe, Cretáceo Inferior do Nordeste do Brasil", Anais da Academia Brasileira de Ciências, 60: 460-469
  6. ^ Veldmeijer, A. J. (2003). Preliminary description of a skull and wing of a Brazilian Cretaceous (Santana Formation; Aptian-Albian) pterosaur (Pterodactyloidea) in the collection of the AMNH. PalArch’s Journal of Vertebrate Palaeontology 0, 1-14.
  7. ^ a b Andres, B.; Myers, T. S. (2013). "Lone Star Pterosaurs". Earth and Environmental Science Transactions of the Royal Society of Edinburgh: 1. doi:10.1017/S1755691013000303. 
  8. ^ a b Pinhiero, F.L.; Taissa, Rodrigues (2017). "Anhanguera taxonomy revisited: is our understanding of Santana Group pterosaur diversity biased by poor biological and stratigraphic control?". PeerJ. 5: e3285. doi:10.7717/peerj.3285. 
  9. ^ a b Veldmeijer, A.J. (2003). "Description of Coloborhynchus spielbergi sp. nov. (Pterodactyloidea) from the Albian (Lower Cretaceous) of Brazil." Scripta Geologica, 125: 35-139.
  10. ^ a b Martins Neto, R.G. (1986). Pricesaurus megalodon nov. gen. nov. sp. (Pterosauria, Pterodactyloidea), Cretaceo Inferior, chapada do Araripe (NE-Brasil). Ciência e Cultura 38(7): 756-757 [Portuguese]
  11. ^ Felipe Lima Pinheiro, Cesar Leandro Schultz, Rafael Gioia Martins-Neto† & José Artur Ferreira Gomes de Andrade, 2012, "What is “Pricesaurus megalodon”? Reassessment of an enigmatic pterosaur", Revista Brasileira de Paleontologia, 15(3): 262-272

Further reading[edit]

  • Campos, D. A., and Kellner, A. W. A. (1985). "Panorama of the Flying Reptiles Study in Brazil and South America (Pterosauria/ Pterodactyloidea/ Anhangueridae)." Anais da Academia Brasileira de Ciências, 57(4):141–142 & 453-466.
  • T. Rodrigues and A. W. A. Kellner. (2008). Review of the pterodactyloid pterosaur Coloborhynchus. Zitteliana B 28:219-228.