Gekkos and snakes: Not a novel hypothesis

Earlier
here and here we looked at what I thought was a novel nesting for terrestrial and aquatic (sighted) snakes with geckos (and blind snakes nest with Lanthanotus.) Then I ran across several previous cladograms that recovered the same or similar data with regard to snakes and geckos. Here they are (Figs. 1-4). Seems as though geckos and snakes have been flirting with one another in several prior cladograms.

snakes-gekkos-evans-barbadillo

Evans and Barbadillo 1998 nested snakes with geckos, Dibamus and amphisbaenids, but apart from Ardeosaurus and Eichstaettisaurus, which the large reptile tree nested with basal snakes, like Adriosaurus and Pontosaurus. Note the nesting of suprageneric taxa, rather than generic taxa. Note to readers: Try to use species or specimens and let the clades form by themselves without presupposing even the most obvious suprageneric clades. Bavarisaurus, by the way, is not a squamate, but nests outside of the Squamata in the large reptile tree.

snakes-gekkos-caldwell-1999

Caldwell 1999 sort of nested geckos with snakes, but only because that node was unresolved with regard to other clades too.

snakes-gekkos-evans-wang-2005

Evans and Wang 2005 nested geckos + skinks with snakes + amphisbaenids. Here three taxa in blue boxes nest outside of the Squamata in the large reptile tree.

Wu 1996 nested geckos with snakes.

Wu 1996 nested geckos with snakes.

Wu et al. 1996 nested snakes with geckos and Dibamus.

So when did things change?

Caldwell 1999 connected snakes with mosasaurs and resurrected Pythonomorpha.

Figure 5. Conrad 2008 nested snakes with amphisbaenids, which the large reptile tree nested with skinks.

Figure 5. Conrad 2008 nested snakes with amphisbaenids, which the large reptile tree nested with skinks.

Conrad 2008 nested snakes with amphisbaenids.

Figure 6. Gauthier et al 2012 also nested snakes with amphisbaenids. But note how close Adriosaurus and Pontosaurus (nesting with mosasaurs) are to geckos! Click to enlarge.

Figure 6. Gauthier et al 2012 also nested snakes with amphisbaenids. But note how close Adriosaurus and Pontosaurus (nesting with mosasaurs) are to geckos! Click to enlarge.

Gauthier et al. 2012 also nested both blind burrowing and sighted terrestrial/aquatic snakes with amphisbaenids. Here (Fig. 6) it is interesting to note how close Adriosaurus and Pontosaurus nest with Eichstaettisaurus and the geckos.

Jucaraseps is a key taxon that has been largely overlooked. It has the first loose premaxilla in the lineage. Even so, the removal of about five taxa on both sides of Jucaraseps are needed in the large reptile tree to shift terrestrial snakes with blind snakes.

References
Caldwell MW 1999. Squamate phylogeny and the relationships of snakes and mosasauroids. Zoological Journal of the Linnean Society 125:115–147.
Caldwell MW 2006. A new species of Pontosaurus (Squamata, Pythonomorpha) from the Upper Cretaceous of Lebanon and a phylogenetic analysis of Pythonomorpha. Memorie della Società Italiana di Scienze Naturali e del Museo Civico di Storia Naturale di Milano 34:1–42.
Conrad JL 2008. Phylogeny and systematics of Squamata (Reptilia) based on  morphology. Bulletin of the American Museum of Natural History 310:1–182.
Caldwell MW and Palci A 2010. A new species of marine ophidiomorph lizard, Adriosaurus skrbinensis, from the Upper Cretaceous of Slovenia. Journal of Vertebrate Paleontology 30:747-755. doi:10.1080/02724631003762963.
Dal Sasso C and Pinna G 1997. Aphanizocnemus libanensis n. gen. n. sp., a new dolichosaur (Reptilia, Varanoidea) from the Upper Cretaceous of Lebanon. Paleontologia Lombarda 7:1–31.
Evans SE and  Barbadillo LJ 1998. An unusual lizard (Reptilia: Squamata) from the Early Cretaceous of Las Hoyas, Spain. Zoological Journal of the Linnean Society 124: 235–265.
Evans SE and Wang Y 2005. Early Cretaceous lizard Dalinghosaurus from China. Acta Palaeontologica Polonica 50: 725–742.
Gauthier JA 2012. Assembling the squamate tree of life: Perspectives form the phenotype and the fossil record. Bulletin of the Peabody Museum of Natural History 53(1):3-308.
Haas G 1979. On a new snakelike reptile from the Lower Cenomanian of Ein Jabrud, near Jerusalem. Bulletin du Muséum national d’Histoire Naturelle de Paris Ser. 4 (1):51-64.
Kornhuber A 1901. Opetisaurus bucchichi, eine neue fossile Eidechse aus der unteren Kreide von Lesina in Dalmatien. Abhandlungen der geologischen Reichsanstalt Wien 17:1-24.
Lee MSY and Caldwell MW 1998. Anatomy and relationships of Pachyrhachis problematicus, a primitive snake with hindlimbs. Philosophical Transactions of the Royal Society London B 353:1521-1552.
Palci A and Caldwell MW 2007. Vestigial forelimbs and axial elongation in a 95 million-year-old non-snake squamate. Journal of Vertebrate Paleontology 27:1-7. doi:10.1671/0272-4634(2007)27[1:VFAAEI]2.0.CO;2.
Pierce SE and Caldwell MW 2004. Redescription and phylogenetic position of the Adriatic (Upper Cretaceous; Cenomanian) dolichosaur Pontosaurus lesinensis (Kornhuber, 1873). Journal of Vertebrate Paleontology 2:373-386.
Seeley HG 1881. On remains of a small lizard from Neocomian rocks of Comen, near Trieste, preserved in the Geological Museum of the University of Vienna. Quarterly Journal of the Geological Society of London 37:52-56.
Wu, X.-C., D.B. Brinkman DB and Russell AP 1996.Sineoamphisbaena hexatabularis hexatabularis:an amphisbaenian (Diapsida: Squamata) fromthe Upper Cretaceous redbeds at Bayan Mandahu(Inner Mongolia, People’s Republic of China), and comments on the phylogenetic relationships of the Amphisbaenia. Canadian Journal of Earth Sciences 33: 541–577.

wiki/Adriosaurus
wiki/Pachyrhachis
wiki/Aphanizocnemus
wiki/Pontosaurus

 

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