The Family Tree of the Pterosauria 19 – The Ornithocheiridae part 3 of 3

In part 1 of the Ornithocheiridae we looked at the base of this large clade of long-winged soaring pterosaurs. In part 2 we looked at ColoborhynchusIstiodactylus and their kin. Here in part 3 look at more derived taxa such as Anhanguera and Liaoningopterus.

The Ornithocheiridae.

Figure 1. The Ornithocheiridae. Click to enlarge and expand.

We’ll Continue with Brasileodactylus
Brasileodactylus araripensis AMNH 24444 (Kellner, 1984; Veldmeijer 2003b) was originally described from just the anterior jaws and later a complete skull and other elements were found. It was derived from a sister to Coloborhynchus  and Haopterus (see part 1), skipping the istiodactylid clade (part 2). Distinct from Coloborhynchus, the skull of Brasileodactylus had no crest. The posterior premaxillary teeth were quite long. So were the matching dentary teeth. The squamosal had a dorsal process that gave the lateral temporal fenestra the appearance of a human ear. The lacrimal protruded into the orbit. The jugal was expanded anteriorly into the antorbital fenestra. The antorbital fenestra was shorter.

Barbosania 
Barbosania gracilirostris (Elgin and Frey 2011) was considered close to Brasileodactylus and was similar in size. The original report stated, “While elements of the cranium appear to suture very early in ontogeny (Kellner and Tomida 2000) all ornithocheiroids recovered from the Romualdo Member of the Santana Formation are considered to be ontogenetically immature based on the lack of fusion in the postcranial skeleton.” Actually this is a phylogenetic signal. As derived lizards, pterosaurs did not follow archosaur fusion patterns.

Ludodactylus.

Figure 2. Click to enlarge. Ludodactylus.

Ludodactylus
Ludodactylus sibbicki SMNK PAL 3828 (Frey, Martill and Buchy 2003) is known from a skull with the unusual combination of a cranial crest and teeth. Distinct from Brasileodactylus, the skull of Ludodactylus was shorter overall with a parietal (cranial) crest with a frontal leading edge. The jugal was not expanded into the antorbital fenestra. The orbit was narrower. The postorbital was more robust. The mandible was more robust and was upturned anteriorly with smaller teeth posteriorly.

Cearadactylus
Cearadactylus atrox 
formerly: SMNK PAL 3828 and CB-PV-F-O93, now: UFRJ MN 7019-V (Leonardi and Borgomanero 1985) Cenomanian, Early Cretaceous, ~90 mya, ~57 cm skull length is known from a skull with an unusual history. Originally it was put together with the premaxilla and anterior dentary switched. Distinct from Brasileodactylus, the skull of Cearadactylus had a wide spoonbill or rosette tip from which erupted giant teeth. The maxillary teeth were tiny. The mandible was deeper, but flatter anteriorly.

Cearadactylus ligabuei CCSRL 12692/12713 (Dalla Vecchia 1993) was similar but had a distinctly shorter rostrum and smaller teeth with an upturned premaxilla. The tip was not a spoonbill, but the middle of the rostrum was narrowed or pinched in dorsal view. The jugal was more gracile.

Liaoningopterus

Figure 3. Click to enlarge. Liaoningopterus

Liaoningopterus
Liaoningopterus gui IVPP V 13291 (Wang and Zhou 2003) Cenomanian, Early Cretaceous, ~90 mya, ~61 cm skull length. Distinct from Cearadactylus, the skull of Liaoningopterus was low anteriorly and very tall posteriorly. A very low crest surmounted the snout tip. Only one premaxillary tooth was enlarged to fang status. It is the largest tooth known for any pterosaur. The anterior dentary was expanded.

Anhanguera

Figure 4. Click to enlarge. Anhanguera.

Anhanguera
Anhanguera piscator IVPP V 13291 (A. bittersdorffi No. 40 Pz-DBAV-UERJ Campos & Kellner, 1985; A. santanae AMNH 22555 Wellnhofer 1985; A. piscator, Kellner and Tomida 2000) Aptian, Early Cretaceous ~110 mya, ~60 cm skull length. Distinct from Liaoningopterus, the skull of Anhaguera had a longer premaxillary crest and smaller teeth. The anterior dentary formed a keel. The squamosal did not rise to form an “ear” shape of the lateral temporal fenestra. The tail was robust and had elongated vertebrae distally. Distinct from Brasileodactylus, manual 4.1 extended to the elbow when folded. Postcranially Anhanguera was most similar to SMNS PAL 1136, but without such a deep sternal complex keel and deep torso. The foot had very short metatarsals and elongated phalanges.

In Summary
The Ornithocheiridae is one of the few pterosaur clades without tiny members. Then again, from Yixianopterus at the base to Anhanguera as the most derived taxon, the morphology of this clade did not go through major changes. Trends toward the development and loss of a snout tip crest, more robust forelimbs and more gracile hindlimbs, an increase in the size of the antorbital fenestra in istiodactylids are all apparent. From the wing/leg ratios it seems apparent that this clade spent more time on the wing and less on the ground. Take-off was likely into the wind with a minimum take-off run from locations near steady and constant ocean breezes. A lack of skeletal fusion (sacrals, scapula/coracoid) permeates this clade, with some of the largest specimens lacking fusion. Fusion did affect some members, but the pattern was phylogenetic, not ontogenetic. The warped deltopectoral crest exhibited by some ornithocheirids has linked them to Pteranodon, but the morphology is distinct and the development was by convergence.

As always, I encourage readers to see specimens, make observations and come to your own conclusions. Test. Test. And test again.

Evidence and support in the form of nexus, pdf and jpeg files will be sent to all who request additional data.

References
Campos, D de A and Kellner AW 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.
Dalla Vecchia FM 1993. Cearadactylus? ligabuei, nov. sp., a new Early Cretaceous (Aptian) pterosaur from Chapada do Araripe (Northeastern Brazil)”, Bolletini della Societa Paleontologica Italiano, 32: 401-409.
Elgin RA and Frey E 2011. A new ornithocheirid, Barbosania gracilirostris gen. et sp. nov. (Pterosauria, Pterodactyloidea) from the Santana Formation (Cretaceous) of NE Brazil. Swiss Journal of Palaeontology. DOI 10.1007/s13358-011-0017-4.
Frey E, Martill DM and Buchy M-C 2003. A new crested ornithocheirid from the Lower Cretaceous of northeastern Brazil and the unusual death of an unusual pterosaur: In: Buffetaut, E., and J.-M. Mazin, Eds. Evolution and Palaeobiology of Pterosaurs. – London, Geological Society Special Publication 217: p. 55-63.
Kellner AWA 1984. Ocorrência de uma mandibula de pterosauria (Brasileodactylus araripensis, nov. gen.; nov. sp.) na Formação Santana, Cretáceo da Chapada do Araripe, Ceará-Brasil. Anais XXXIII Cong. Brasil. de Geol, 578–590. Rio de Janeiro
Kellner AWA and Tomida Y 2000. Description of a new species of Anhangueridae (Pterodactyloidea) with comments on the pterosaur fauna from the Santana Formation (Aptian–Albian), Northeastern Brazil. National Science Museum Monographs, 17:1–135.
Leonardi G and Borgomanero G 1985. Cearadactylus atrox nov. gen., nov. sp.: novo Pterosauria (Pterodactyloidea) da Chapada do Araripe, Ceara, Brasil. Resumos dos communicaçoes VIII Congresso bras. de Paleontologia e Stratigrafia, 27: 75–80.
Unwin DM 2002. On the systematic relationships of Cearadactylus atrox, an enigmatic Early Cretaceous pterosaur from the Santana Formation of Brazil. Mitteilungen Museum für Naturkunde Berlin, Geowissenschaftlichen Reihe 5: 1239–263.
Veldmeijer AJ 2003b. Preliminary description of a skull and wing of a Brazilian Cretaceous (Santana Formation; Aptian-Albian) pterosaur (Pterodactyloidea) in the collection of the AMNH. PalArch, series vertebrate palaeontology 1: 1-13.
Veldmeijer AJ, Meijer HJM and SignoreM 2009. Description of Pterosaurian (Pterodactyloidea: Anhangueridae, Brasileodactylus) remains from the Lower Cretaceous of Brazil, DEINSEA 13: 9-40
Vila Nova BC, Kellner AWA, Sayão JM 2010. Short Note on the Phylogenetic Position of Cearadactylus Atrox, and Comments Regarding Its Relationships to Other Pterosaurs. Acta Geoscientica Sinica 31 Supp.1: 73-75.
Wellnhofer P 1985. Neue Pterosaurier aus der Santana-Formation (Apt) der Chapada do Araripe, Brasilien. Paläontographica A 187: 105–182.

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