This diagnosis utilizes a variety of character claims which might be found in other Triassic archosauromorph lineages (elizabeth

This diagnosis utilizes a variety of character claims which might be found in other Triassic archosauromorph lineages (elizabeth

six.2.1 Diagnosis the fresh new Genus Revueltosaurus

This new holotypes of Roentgen. callenderi (NMMNH P-4957), “Revueltosaurus” hunti (NMMNH P-29357), as well as the recently attributed variety “Revueltosaurus” (= Pekinosaurus) olseni (YPM 7666; Heckert et al., 2012 ) per happened to be one isolated enamel which was the basis having their specific analysis. Lately, Heckert et al. ( 2012 ) detected the newest genus Revueltosaurus (spanning R. callenderi, Roentgen. hunti, and Roentgen. olseni) using the adopting the blend of character states: size (enamel crowns everything 7 so you can fifteen-mm significant); multiple short denticles (more eight for each carina) which can be counterbalance (sub-perpendicular) into tooth margin; denticles proportionately small and frequently used into enamel because of the real occlusion; insufficient a real cingulum; premaxillary tooth crowns which might be just as much as doubly high as maxillary/dentary tooth crowns and weakly recurved; and you may maxillary/dentary tooth crowns phyllodont (leaf-shaped). grams., Ezcurra, 2016 ). Including, the combination of one’s sized tooth, the number of the brand new denticles, together with direction of denticles convergence with other distantly related taxa (elizabeth.g., Silesaurus opolensis, Dzik, 2003 ; Azendohsaurus madagaskarensis, Flynn ainsi que al., 2010 ). The character “denticles proportionately small and regularly worn toward tooth of the direct occlusion” lacks reliability when it comes to what is actually sensed “small,” as well as the wear trend is hard so you’re able to eliminate various other taxa and you will utilizes a particular age of enamel when you look at the replacement for stage (i.elizabeth., young teeth wouldn’t be diagnosable since there wouldn’t be worn). In addition, its lack of apomorphic profile claims (e.g., lack of cingulum) should not be included in a diagnosis, because they’re symplesiomorphies. In addition, new project regarding enamel reputation centered on just one enamel (e.grams., premaxillary enamel crowns was just as much as two times as extreme since the maxillary/dentary enamel crowns and weakly recurved; maxillary/dentary tooth crowns leaf molded) cannot be determined on the original sort of topic, as well as with additional white teeth regarding same area, merely craniodental question having pearly whites also have the fresh relationship out-of tooth profile and you may tooth position. Ergo, the fresh proposed tooth reputation of the holotype connexion eЕџleЕџme sorunu pearly whites out-of K. hunti and you will P. olseni is believed considering an inferred romantic experience of R. callenderi, that is known out of craniodental situation that have pearly whites (get a hold of more than). In conclusion, the latest genus Revueltosaurus sensu lato cannot be adequately and sustainably identified according to the types of product regarding Roentgen. callenderi, K. hunti, and you may P. olseni and we also thus limitation the brand new genus to one varieties, Roentgen. callenderi. As such, we propose that “R”. hunti keep up with the subjective junior word Krzyzanowskisaurus hunti since erected from the Heckert ( 2005 ) and you can “R”. olseni keep up with the personal senior synonym Pekinosaurus olseni. I subsequent warning the task of any present separated tooth taxa so you can Revueltosaurus.

We do understand that later on, with additional over point, Roentgen. callenderi, Krzyzanowskisaurus hunti, and you may Pekinosaurus olseni may portray good monophyletic genus Revueltosaurus, however, an assignment of all the around three varieties to 1 genus is not already you are able to because renders a the priori presumption regarding dating (see less than) that is synchronous to your original disagreement that Revueltosaurus pearly whites were assignable in order to Ornithischia before everything else. This may provides undesirable streaming consequences to the then macroevolutionary education (e.grams., biogeography and paleocology). Instead, it is very possible these particular taxa may turn aside getting distantly relevant.

six.dos.2 What is Krzyzanowskisaurus hunti?

Heckert ( 2002 ) described “Revueltosaurus” hunti, after allotted to new genus Krzyzanowskisaurus (Heckert, 2005 ), centered on separated white teeth throughout the Los Esteros Member of this new Santa Rosa Development (Dockum Category) when you look at the main The fresh Mexico and Blue Mesa Person in the latest Chinle Formation from inside the eastern Arizona (method of locality out of A beneficial. geoffreyi-look for ), and also also been accepted throughout the all the way down Chinle Creation within the southeastern Utah ( , p. 16). Krzyzanowskisaurus hunti white teeth is actually notable regarding Roentgen. callenderi white teeth of the exposure of good ridge (“cingulum”) toward the base of tooth top, hence connects on carinae that’s usually denticulated (Heckert, 2002 , 2005 ; Irmis, Parker, mais aussi al., 2007 ; Data 14a, b). Originally, Krzyzanowskisaurus is called considering the disparate morphology of your own pearly whites ranging from both forms and the dispute that Krzyzanowskisaurus teeth however had been assignable so you’re able to an ornithischian in place of a beneficial pseudosuchian (Heckert, 2005 ). Irmis, Parker, ainsi que al. ( 2007 ) disagreed to the assignment away from Krzyzanowskisaurus hunti to the Ornithischia mainly based on the equivalent objections explaining the issues of delegating separated pearly whites to ornithischians just like the displayed in the past in addition to design that Heckert ( 2002 , 2005 ) defined as a good “cingulum” was not homologous with the exact same formations for the ornithischian dinosaurs. Furthermore, Irmis, Parker, et al. ( 2007 ) also indexed that a Revueltosaurus-such as for example squamosal, quadrate, and you will osteoderms was in fact as well as bought at the same Washington locality due to the fact Krzyzanowskisaurus hunti white teeth, exactly as had taken place in the method of locality for Roentgen. callenderi (Take a look ainsi que al., 2005 ).

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