Several “aberrant” taxa have been promoted recently.
Vancleavea was postulated (Nesbitt et al. 2009) to be an aberrant archosauriform close to Doswellia, Turfanosuchus, Chanaresuchus and Erythrosuchus. Nested in the large reptile tree it turned out to be a sister to Helveticosaurus, a thalattosaur.
Pterosaurs have been traditionally and most recently postulated (Nesbitt 2011) to be aberrant archosaurs close to parasuchians and dinosaurs. The large reptile tree nested them with fenestrasaurs like Longisquama.
Turtles were postulated to be aberrant archosaurs, sauropterygians and pareiasaurs. The large reptile tree nested them distinct from but closer to pareiasaurs, close to the largely forgotten diadectid, Stephanospondylus.
Diadectes, Chroniosuchus and Limnoscelis (Berman, Reisz and Scott 2010 – who reported, “diadectomorphs comprise a nonamniote sister clade to all amniotes”) were traditionally postulated to be outgroup taxa to the Reptilia . The large reptile tree found they all nested within the Reptilia.
Mesosaurus was postulated (Laurin and Reisz 1995; Modesto 2006, 2010) to be an aberrant basal reptile between synapsids and milllerettids + captorhinids. The large reptile tree nested mesosaurs at the base of the Enaliosauria (plesiosaurs, thalattosaurs and ichthyosaurs), close to Wumengosaurus and Claudiosaurus.
Tanystropheus was considered an aberrant prolacertiform, but here it nests with a new clade of lizards, the Tritosauria, along with an ‘island of misfit toys’ including drepanosaurs, Sharovipteryx, Longisquama and pterosaurs.
Colobomycter was originally considered an aberrant caseid pelycosaur (Vaughn 1958). Later Modesto and Reisz (2008) considered it close to Acleistorhinus. The large reptile tree nested it with basal placodonts.
Choristoderes, like Doswellia and Champsosaurus, were considered aberrant proterochampsids (Dilkes and Sues 2009) and basal lepidosauromorphs respectively. Here they nest together derived from Youngina BPI 2871.
Lotosaurus was considered an aberrrant herbivorous rauisuchid close to the carnivorous Arizonasaurus (Nesbitt 2003). The large reptile tree nested it with Silesaurus and the poposaurids, within the Dinosauria.
Diandongosuchus was considered an aberrant basal poposaurid. Here it nests as a basal parasuchian, not far from Proterochampsa.
Scleromochlus was considered (Benton 1999, Senter 2003) an aberrant sister to pterosaurs (or pterosaurs were aberrant, take your pick because they are wildly different). Here it nests with other basal bipedal crocs.
Effigia and Shuvosaurus were considered (Nesbitt and Norell 2006; Brusatte et al. (2010) aberrant poposaurid rauisuchians that only looked like dinosaurs. The large reptile tree nested it with other poposaurids within the Dinosauria.
Well, basically this is a summary of most of the PterosaurHeresies highlights, all arrived at by applying the misfit taxa to a larger matrix granting more opportunity to nest most parsimoniously. A priori assumptions are fine, if you’re sure of what you have. If not… if you have an aberrant fossil, then test it in the large reptile tree to see what it recovers before making your assumptions. It will save you from having to read a criticism here.
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.
Benton MJ 1999. Scleromochlus taylori and the origin of the pterosaurs. Philosophical Transactions of the Royal Society London, Series B 354 1423-1446. Online pdf
Berman, DS, Reisz RR, Scott D, Henrici AC, Sumida SS and Martens T 2000. Early Permian bipedal reptile. Science 290: 969-972.
Berman DS Reisz RR and Scott D 2010. Redescription of the skull of Limmoscelis paludis Williston (Diadectomorpha: Limnoscelidae) from the Pennsylvanian of Canon del Cobre, northern New Mexico: In: Carboniferous-Permian Transition in Canon del Cobre, Northern New Mexico, edited by Lucas, S. G., Schneider, J. W., and Spielmann, New Mexico Museum of Natural History & Science, Bulletin 49, p. 185-210.
Irmis RB, Nesbitt SJ, Padian K, Smith ND, Turner AH, Woody D and Downs A 2007. A Late Triassic dinosauromorph assemblage from New Mexico and the rise of dinosaurs. Science 317 (5836): 358–361. doi:10.1126/science.1143325. PMID 17641198.
Laurin M and Reisz R 1995. A reevaluation of early amniote phylogeny. Zoological Journal of the Linnean Society, 113: 165–223.
Modesto SP and Reisz RR 2008. New material of Colobomycter pholeter, a small parareptile from the Lower Permian of Oklahoma.
Nesbitt SJ, Irmis RB, Parker WG, Smith ND, Turner AH and Rowe T 2009. Hindlimb osteology and distribution of basal dinosauromorphs from the Late Triassic of North America. Journal of Vertebrate Paleontology 29 (2): 498–516. doi:10.1671/039.029.0218.
Nesbitt SJ 2003. Arizonasaurus and its implications for archosaur divergence. Proceedings of the Royal Society, London B (Suppl.) 270, S234–S237. DOI 10.1098/rsbl.2003.0066
Nesbitt S 2007. The anatomy of Effigia okeeffeae (Archosauria, Suchia), theropod-like convergence, and the distribution of related taxa. Bulletin of the American Museum of Natural History, 302: 84 pp. online pdf
Nesbitt SJ 2011. The early evolution of archosaurs: relationships and the origin of major clades. Bulletin of the American Museum of Natural History 352: 292 pp.
Nesbitt SJ and Norell MA 2006. Extreme convergence in the body plans of an early suchian (Archosauria) and ornithomimid dinosaurs (Theropoda). Proceedings of the Royal Society B 273:1045–1048. online
Nesbitt SJ, Stocker MR, Small BJ and Downs A 2009. The osteology and relationships of Vancleavea campi (Reptilia: Archosauriformes). Zoological Journal of the Linnean Society 157 (4): 814–864. doi:10.1111/j.1096-3642.2009.00530.x.
Parker WG., et al. 2005. The Pseudosuchian Revueltosaurus callenderi and its implications for the diversity of early ornithischian dinosaurs. In Proceedings of the Royal Society London B 272(1566):963–969.
Romer AS and Price LI 1940. Review of the Pelycosauria. Geological Society of America Special Papers 28: 1-538.
Senter P 2003. Taxon Sampling Artifacts and the Phylogenetic Position of Aves. PhD dissertation. Northern Illinois University, 1-279.
Vaughn PP 1958. On a new pelycosaur from the Lower Permian of Oklahoma, and on the origin of the family Caseidae. Journal of Paleontology 32:981–991.