Lineage (NCBI): root » Eukaryota » Opisthokonta » Metazoa » Coelomata » Craniata <chordata> » Euteleostomi » Sauropsida » Coelurosauria » Aves » Charadriiformes » Cepphus » Cepphus carbo
Loxocemidae Look for this name in NCBI Wikipedia Animal Diversity Web
http://palaeo-electronica.org/content/fc-6 Head, 2015
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Minimum age is based on faunal correlation of Medicine Pole Hills fossil localities (Bowman County, North Dakota) with Flagstaff Rim localities (Natrona County, Wyoming), which are overlain by an ash layer (Ash B) that is 40Ar/39Ar dated at 35.41 ± 0.14 Ma (Obradovich et al., 1995). Smith (2011) recalculated the minimum estimate for the Medicine Pole Hills local fauna at 35.2 Ma.
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PTRM 19378 is united with Loxocemidae on the basis of: 1) dorsal head expanded into broad plate; 2) dorsal head lies wholly in saggital plane; 3) well-defined lip present on lateral side of dorsal margin (Smith, 2013).
Smith, K.T. 2013. New constraints on the evolution of the snake clades Ungaliophiinae, Loxocemidae and Colubridae (Serpentes), with comments on the fossil history of Erycine boids in North America. Zoologischer Anzeiger, 252:157-182.
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