Paramacellodus oweni (Hoffstetter 1967; Evans and Chure 1998; Meyer et al. 2021; Late Jurassic; DIN 191514) is a tiny squamate found in the Morrison Formation. Here it nests basal to tiny Retinosaurus and Eichstattisaurus in the lineage of snakes.

Tchingisaurus multivagus (Alifanov 1993. 84.9 to 70.6 Ma) Late Cretaceous was considered a macrocephalosaurid like Macrocephalosaurus by Gauthier et al. 2012, but here nests as a basal gekkonid, not far from the basal skink, Acanthodactylus and the basal snake Ardeosaurus. It was derived from a sister to Eolacerta .

Distinct from Eolacerta, the skull of Gekko was longer and lower, twice as wide as tall. The skull table was flat. The jugal was largely absent except for a sliver beneath the anterior orbit. The jawline was straight. The orbit sas smaller than the postorbital length. The postorbital portion was elongated but the postorbital was considerably reduced. The orbit, upper and lateral temporal fenestrae were confluent with no bars separating them. The postorbital and parietal had a long contact. The parietals were comparatively broad. Vomernasal openings are created by lateral expansion of the vomers to contact the maxilla. The ventral mandible was straight.

Chometokadmon fitzingeri (Costa 1864, Evans, Raia and Barbera 2006; Early Cretaceous) was originally considered a lizard, then an anguimorph (basal to varanids and helodermatids). Here it nests as a basal gekko with very long toes. Apparently the squamosal + quadrate is just a quadrate. Other misidentified bones are shown here.

Alifanov VR 1993. New lizards of the family Macrocephalosauridae (Sauria) from the Upper Cretaceous of Mongolia, critical remarks on the systematics of the Teiidae. Paleontological Journal 27(1):70-90.

Arnold EN and Poinar G 2008. A 100-million-year old gecko with sophisticated adhesive toe pads, preserved in amber from Myanmar (abstract). Zootaxa page one.

Costa OG 1864. Paleontologia del Regno di Napoli, III. Atti dell’Accademia Pontaniana 8, 1e198.

Evans SE and Chure DJ 1998. Paramacellodid lizard skulls from the Jurassic Morrison Formation at Dinosaur National Monument, Utah. Journal of Vertebrate Paleontology. 18 (1): 99–114.

Evans SE, Raia P, Barbera C 2006. The Lower Cretaceous lizard genus Chometokadmon from Italy. Cretaceous Research 27:675-683.

Gauthier JA,Kearney M, Maisano JA, Rieppel O and Behlke ADB 2012. Assembling the Squamate Tree of Life: Perspectives from the Phenotype and the Fossil Record. Bulletin of the Peabody Museum of Natural History 53(1):3–308.

Hoffstetter R 1967. Coup d'oeil sur les Sauriers (=lacertiliens) des couches de Purbeck (Jurassique supérieur d'Angleterre). Coloques Internationaux du Centre National de la Recherche Scientifique 163:349–371.

Meyer D, Brownstein CD and Gauthier J 2021. Computed tomography reveals a Jurassic stem-gekkotan from the Morrison Formation. Journal of Vertebrate Paleontology abstracts.

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