Dorsal Ribs Dorsal and Sacral Vertebrae Prepubes Gastralia
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A FLIGHTLESS PTEROSAUR, JME-Sos2428 Homoeosaurus Jianchangnathus David Peters Huehuecuetzpalli Pterorhynchus A normal pterosaur wing compared to Macrocnemus BES SC111 dorsal and sacral vertebrae Kunpengopterus [email protected] dorsal ribs Macrocnemus T4822 Wukongopterus JME-Sos 2428 in situ — the vestigial wing of Sos 2428. Macrocnemus T2472 Darwinopterus Dinocephalosaurus Scaphognathus crassirostris davidpetersstudio.com Jesairosaurus Scaphognathus SMNS 59395 and where are the wing bones?? Hypuronector Scaphognathus Maxberg Vallesaurus TM 13104 This tiny specimen phylogenetically nests close to Sos 2428. Drepanosaurus St Charles, MO 63303 Gmu10157 Megalancosaurus BSp 1986 XV 132 It shows no sign of wing reduction, Amotosaurus Pterodactylus? micronyx-Pester Langobardisaurus but does have wide gastralia and ribs. Tanytrachelos B St 1936 I 50 n30 Tanystropheus a Cycnorhamphus JME-Sos2428 is a largely complete, crushed, Tanystropheus k and q Moganopterus Cosesaurus Feilongus Sharovipteryx Yixianopterus Solnhofen pterosaur. It was previously Note how small the humerus is. Longisquama MSNM V 3881 (Lateral view below, in situ below far right.) MPUM 6009 Lebanon Ornithocheirid Complete Radius/ulna length estimated. Raeticodactylus JZMP embryo considered another specimen of Ardeadactylus Austriadactylus holotype Haopterus Austriadactylus-SC332466 Boreopterus Dimorphodon macronyx Zhenyuanopterus (formerly Pterodactylus) longicollum (neotype: Preondactylus Arthurdactylus Peteinosaurus Ex3359 Coloborhynchus spielbergi Carniadactylus Criorhynchus SMNS 56603). However, a closer look reveals MCSNB 8950 Ornithocheirid SMNK PAL 3854. IVPP V13758 embryo Nurhachius Mesadactylus Jenson and Padian SMNS 1136 PAL important dierences. Dimorphodon? weintraubi Istiodactylus Dendrorhynchoides Brasileodactylus GLGMV0002 Ludodactylus Flathead anurognathid Guidraco Anurognathus Cearadactylus ligabuei CAG IG 02-81 Cearadactylus atrox The skull is longer than the cervical series in Jeholopterus Liaoningopterus Batrachognathus Anhanguera piscator Eudimorphodon ranzii Ornithocephalus JME-SosSos2428, but not in Ardeadactylus. The prepubes Eudimorphodon cromptonellus Eudimorphodon BSp 1994 n9 SOS4593 Changchengopterus n31 SOS4006 slender cervical ribs are each a centrum length Campylognathoides Paris C4 SMNS 81775 Ningchengopterus Tooth number Campylognathoides zitteli Cz in JME-Sos2428, but they are much shorter in Campylognathoides zitteli C5 Pterodactylus AMNH 1942 n20 Nesodactylus Pterodactylus NHMW 1975 vienna Campylognathoides liasicus C3 Pterodactylus n21 Ardeadactylus. The parasagittally compressed Rhamphorhynchus intermedius n28 Pterodactylus n37 coracoid Rhamphorhynchus BSPG1960 I 470A Pterodactylus FreyTisch Bellubrunnus Pterodactylus antiquus n4 dorsal vertebrae comprise only 40% of the torso m4.4 Qinglongopterus Pterodactylus BM0007 Rhamphorhynchus longicaudus n10 Diopecephalus n58 gastralia Rhamphorhynchus Vienna No6 length in JME-Sos2428, but 66% in the more scapula Rhamphorhynchus n11 BMNH 42736 JME-Sos 2479, known from a skull, phylogenetically nests with Sos2428. Rhamphorhynchus ROM 55352 No12 Rhamphorhynchus longiceps No23 typical pterosaur, Ardeadactylus. Conversely, in Rhamphorhynchus Thermopolis Germanodactylus rhamphastinus carpals Rhamphorhynchus n62 Eosipterus Rhamphorhynchus darkwing JME Germanodactylus JME-Sos2428 the robust sacral series extends Rhamphorhynchus MTM V2008.33.1 Germanodactylus BMM Private m4.3 preaxial carpal Rhamphorhynchus n33 MOZ 3625P Rhamphorhynchus n43 Cuspiscephalus for 60% of the torso, 34% in Ardeadactylus. In Rhamphorhynchus n74 Germanodactylus cristatus n61 JME-Sos2428 Rhamphorhynchus n38 azhdarchide? PAL 3830 Rhamphorhynchus n75 pteroid Phobetor JME-Sos2428 the dorsal ribs, sternal ribs and Rhamphorhynchus n52 Dsungaripterus Sordes (no. 57 in the Dorygnathus Donau Noripterus gastralia are relatively twice the lengths of those Dorygnathus SMNS 58127 Nemicolopterus Cacibuteryx Shenzhoupterus Wellnhofer 1970 catalog) mc4 Dorygnathus SMNS 50164 Sinopterus found in Ardeadactylus. The pectoral girdle is TM 10341 Tapejara sternal complex Beipiaopterus Huaxipterus Huanhepterus Tupandactylus gracile in JME-Sos2428, with a scapula and a Mesadactylus Smith Tupuxura longicristatus m4.2 CM 11 426 n44 Thalassodromeus Dublin cast Tupuxura Goshura coracoid half the width of those same elements m4.1 B St 1911 I 31 n42 Germanodactylus Karlsuhe SOS2428 Prejanopterus in Ardeadactylus. The forelimb (wing) elements Ardeadactylus SOS 2179 Elanodactylus humerus Jidapterus No13 Chaoyangopterus LPM-R00076 Eopteranodon are likewise less than half the length and width (SMNS-56603, no. 58 in the Microtuban Aurorazhdarcho Chaoyangopterus holotype Eoazhdarcho Wellnhofer 1970 catalog) Zhejiangopterus Muzquizopteryx of those in Ardeadactylus. The wing nger Quetzalcoatlus Nyctosaurus FHSMVP21 radius/ulna Fenghuangopterus Nyctosaurus FMNH25026 Dorygnathus SMNS 55886 Nyctosaurus UNSM93000 (manual digit 4) is further reduced relative to the partly exposed Dorygnathus Up R 156 Nyctosaurus KJ1 Sericipterus Nyctosaurus KJ2 Dorygnathus purdoni Pteranodon YPM 1179 Angustinaripterus rest of the wing. When folded the unreduced Pteranodon FHSM 2183 St/E1I Pteranodon UUPI R197 MBR 3530.1 n40 rst wing phalanx extends back to the carpus. Ctenochasma elegans private Pteranodon YPM 1177 AMNH 5147 Pteranodon KUVP 2212 skull Gnathosaurus Pteranodon YPM 2594 However, the second wing phalanx is half that Examples of Digital Graphic Segregation in which a complex “roadkill” fossil parts Ctenochasma elegans n45 Pteranodon Jenkins skull Gegepterus Pteranodon CMC VP7203 Gladocephaloideus Pteranodon FHSM 2851 length. The third phalanx is half the second and are color and layer segregated to aid in identication and reconstruction. Ctenochasma n65 B Pteranodon NMC41 358 Propterodaustro Pteranodon KUVP 27821 Pterodaustro Pteranodon FHSM VP339 the fourth is less than half the third. Thus, when Pterodactylus Pterodaustro embryo folded, the distal tip of the reduced wing nger Jianchangnathus and descendants extends just to the elbow. By comparison, in BSPG 1911 I 31 CM 11426 (no. 42 in the (no. 44 in the Ardeadactylus the elbow meets the middle of Wellnhofer 1970 catalog) Wellnhofer 1970 catalog) the second wing phalanx and the two distal phalanges nearly double that length. In JME-Sos2428 the free ngers, digits 1-3, are not Here the vestigial wing bones reduced. Matching the elongated sacrum in have been segregated from JME-Sos2428, the hyperelongated ilium the other very similar rib and extends for 60% of the torso length. However, pectoral elements after they the much smaller pubis, prepubis, ichium and all have been identied. femur are similar in size to those same elements in Ardeadactylus. In JME-Sos2428 the distal tibia and pes are not preserved. When reconstructed, JME-Sos2428 has a relatively CM 11426 BSPG 1911 I 31 JME-Sos 2428 vestigial wing longer and wider torso than any other known (no. 44 in the (no. 42 in the Another possible pterosaur. It also has a reduced wing, half the length Wellnhofer 1970 catalog) Wellnhofer 1970 catalog) ightless pterosaur? and half the chord of the wing of Ardeadactylus when scaled to the same torso length. Such a reduced wing and such an enlarged torso make the prospect of ight rather doubtful by comparison. Moreover, with such morphological dierences, JME-Sos2428 is clearly a distinct genus. JME-Sos = Jura Museum Solnhofen-Sammlung; Eichstatt, Germany.