Pterosauria

Holotype of Alcione elainus. Fig. 6 of: Longrich, N. R., Martill, D. M., & Andres, B. (2018). Late Maastrichtian pterosaurs from North Africa and mass extinction of Pterosauria at the Cretaceous-Paleogene boundary. PLoS biology, 16(3), e2001663. --- Original figure legend: A. elainus FSAC-OB 2, holotype partial skeleton and FSAC-OB 217, metacarpal IV. (A) Holotype right humerus in anterior view, (B) holotype right ulna and radius in anterior view, respectively, (C) holotype sternum in left lateral view, (D) referred metacarpal IV, (E) holotype, distal end of left metacarpal IV and left scapulocoracoid, and (F) holotype right femur in posterior view. Abbreviations: co, coracoid; cr, cristospine; dc, distal condyle; dpc, deltopectoral crest; ect, ectepicondyle; fh, femoral head; gl, glenoid; gt, greater trochanter; hh, humeral head; hum, humerus; mcIV, metacarpal IV, pc, proximal cotyle; pf, pneumatic foramen; rad, radius; scpr, supracondylar process; ste, sternum; uln, ulna.

This diagram illustrates how scientists believe the dinosaur group theropoda shall be classed in a phylogenetic tree, besides Sauropoda and Pterosauria. The main reason of this diagram is to show groups or families which had respiratory system like birds. AS in the diagram is abbreviations for "Airsacs", and ASW means "AirSacs supported by immobile femur and a knee-driven Walk". BL means "Bellow lungs". Airsacs are known in many different theropods, as well as in birds, which most scientists believe are descendants of dinosaurus. Air sacs are found in the primitive Tawa hallae,[1] the abelisaurid Majungasaurus,[2] as well as Allosauroids like Aerosteon.[3] There is also evidence for respiratory systems like penguinss in Deinonychosaurians.[4] The primitive bird Archaeopteryx also had airsacs (Bonde and Christiansen, 2000). It is very likely that Deinonychosaurians had airsacs. We don't know whether Deinonychosauria had a walking/breathing system with immobile thighbones, ASW (like birds) or movable thighbones. However, some people suggsest coeluosaurs had the same type of leg movement as birds ("kneedriven walking").[5] Bellow lungs are lungs like our own, which alternately is filled with air, and thereafter emptied, after which you take a new breath. This type of lungs exist in mammals, most reptiles, and most amphibians (although some frogs get their oxygen through the skin). There is no evidence for airsacs in Ornithischia, so the likely had bellow lungs. References.= ↑ (see the video at http://www.nsf.gov/news/special_reports/tawa/) ↑ (Claessens & O'connor, 2006). ↑ Alcober O.A, Sereno P.C, Larsson H.C.E et.al (2008), "Evidence for Avian Intrathoracic Air Sacs in a New Predatory Dinosaur from Argentina", Public Library of Science Journals. ↑ http://www.stumbleupon.com/su/20q5Z4/news.bbc.co.uk/2/hi/science/nature/7081166.stm ↑ http://www.geol.umd.edu/~tholtz/G104/lectures/104coelur.html.

cast of Quetzalcoatlus northropi humerus 03 - Pterosaurs Flight in the Age of Dinosaurs

cast of Quetzalcoatlus northropi humerus 02 - Pterosaurs Flight in the Age of Dinosaurs

Cast of Quetzalcoatlus northropi humerus 01 - Pterosaurs Flight in the Age of Dinosaurs

Figure 5: Measured and estimated azhdarchid pterosaur neck lengths against approximate wingspans.

Fossil of Quetzalcoatlus, an extinct pterosaur- Took the photo at Senckenberg Museum of Frankfurt

Several members of Pterodactyloidea (top to bottom): Pteranodon, Pterodaustro, the skulls of several pterosaurs (Guidraco, Anhanguera, Tupandactylus, and an unnamed dsungaripterid), Quetzalcoatlus, Aerodactylus, and Coloborhynchus

Several members of Pterodactyloidea (top to bottom): Pteranodon, Pterodaustro, the skulls of several pterosaurs (Guidraco, Anhanguera, Tupandactylus, and an unnamed dsungaripterid), Quetzalcoatlus, Aerodactylus, and Coloborhynchus

Several members of Pterodactyloidea (top to bottom): Pteranodon, Pterodaustro, the skulls of several pterosaurs (Guidraco, Anhanguera, Tupandactylus, and an unnamed dsungaripterid), Quetzalcoatlus, Aerodactylus, and Coloborhynchus

Several members of Pterodactyloidea (top to bottom): Pteranodon, Pterodaustro, the skulls of several pterosaurs (Guidraco, Anhanguera, Tupandactylus, and an unnamed dsungaripterid), Quetzalcoatlus, Aerodactylus, and Coloborhynchus

Several members of Pterodactyloidea (top to bottom): Pteranodon, Pterodaustro, the skulls of several pterosaurs (Guidraco, Anhanguera, Tupandactylus, and an unnamed dsungaripterid), Quetzalcoatlus, Aerodactylus, and Coloborhynchus

Several members of Pterodactyloidea (top to bottom): Pteranodon, Pterodaustro, the skulls of several pterosaurs (Guidraco, Anhanguera, Tupandactylus, and an unnamed dsungaripterid), Quetzalcoatlus, Aerodactylus, and Coloborhynchus

Illustration of the holotype metacarpal of Dermodactylus montanus, a pterosaur from the Jurassic of Wyoming. Reference Colbert EH (1969) A Jurassic Pterosaur from Cuba. American Museum Novitates 2370, 1-26

Tropeognathine pterosaur Siroccopteryx moroccensis Mader andKellner, 1999, LINHM FR016, Kem Kem beds, Morocco, ?Albian–lowerCenomanian. A. Photograph in anterior (A1), left lateral (A2), and dorsal(A3) views. B. Interpretation of the palatal view following Mader andKellner (1999). Photographs courtesy of Megan L. Jacobs. Drawing byRVP based on Mader and Kellner (1999).

Life restoration of Harpactognathus gentryii, a pterosaur from Jurassic USA