Various other wider-level investigation away from archosaur matchmaking by Nesbitt mais aussi al

dos GEOLOGICAL Form

None Parker et al. ( 2005 ) neither Look mais aussi al. ( 2005 ) experimented with a great phylogenetic study of R. callenderi according to the the fresh skeletal point. But not, both organizations detailed multiple features of the Yazar hakkД±nda daha fazla brand new hindlimb which were unambiguous synapomorphies off Pseudosuchia. Parker et al. ( 2005 ) hypothesized a prospective sis-classification relationship with aetosaurs, noting the fresh new morphological parallels of your own squamosal and paramedian osteoderms. An identical condition try suggested by the Hunt mais aussi al. ( 2005 ) centered on unspecified character claims of tarsus and also the osteoderms. Brusatte ainsi que al. ( 2010 ) incorporated Roentgen. callenderi within investigation out of very early archosaur relationships, coding about authored figures and you can descriptions regarding Parker ainsi que al. ( 2005 ) and Search ainsi que al. ( 2005 ). One analysis retrieved Roentgen. callenderi because cousin taxon towards the early-diverging suchian clade Ornithosuchidae. ( 2011 ) recovered Roentgen. callenderi inside a proper-offered standing just like the aunt taxon so you’re able to aetosaurs, a consequence supported by new knowledge (e.g., Butler mais aussi al., 2014 ; ; Nesbitt & Butler, 2013 ; Nesbitt mais aussi al., 2014 ; Nesbitt et al., 2020 ; Nesbitt, Stocker, mais aussi al., 2018 ).

This contribution completely identifies new osteology out of Roentgen. callenderi based on at least several anyone (according to femora count) away from PEFO including three really-maintained related limited skeletons accumulated anywhere between 2005 and 2015, provides osteohistological context, and discusses the latest taxon’s pros to possess wisdom very early suchian evolution.

dos.step 1 Stratigraphic position

It malfunction off Roentgen. callenderi are mainly according to topic off several localities throughout the Chinle Development off Petrified Tree Federal Park (PEFO), Washington, All of us (Profile 1; find Logical Paleontology). Top of the Triassic Chinle Creation in this field constitutes mainly fluvial and you will floodplain strata from changing claystones, siltstones, sandstones, and you can conglomerates (Billingsley, 1985 ; Heckert & Lucas, 2002a ; ). The new Chinle Formation regarding the Petrified Tree Federal Playground town conserves well-identified traditional assemblages regarding vegetation (palynomorphs, makes, wood), invertebrates, and you can vertebrates (e.grams., Ash, 2005 ; Baranyi et al., 2018 ; A beneficial, 1998 ; Irmis, 2005 ; Litwin, Traverse, & Ash, 1991 ; Parker, 2005b , 2006 ; Reichgelt mais aussi al., 2013 ). Really low-dentigerous and you will non-osteoderm specimens off Roentgen. callenderi regarding PEFO, and those explained right here, have been found quickly a lot more than Coated Desert Sandstone step 3 (sensu Billingsley, 1985 ; Lithodendron Clean Sleep sensu Heckert & Lucas, 2002a ) around an element of the Petrified Forest Affiliate (sensu Woody, 2006 ) of your own top the main Chinle Creation (Heckert & Lucas, 2002a ; Irmis, 2005 ; Padian, 1990 ; Parker, 2005b , 2006 ; Parker ainsi que al., 2005 ; Parker & ). Isolated white teeth away from R. callenderi was indeed retrieved off microvertebrate assemblages from reduced in the fresh Chinle Creation during the PEFO, extending the newest stratigraphic range of so it taxon towards the Sonsela Affiliate and you will highest Blue Mesa Member (pick Scientific Paleontology).

The three head localities one to produced the newest specimens off Roentgen. callenderi described here (Research S1) are definitely the Revueltosaurus Quarry (PFV 297), Revueltosaurus Quarry SW (PFV 414), therefore the Offering Website (PFV 231). Those sites are present as paleosols in a stacked fluvial series inside the center of brand new Petrified Forest Member (Atchley et al., 2013 ; Loughney ainsi que al., 2011 ; Parker mais aussi al., 2005 ; Parker & ). PFV 297 and you can PFV 414 are split up spatially by the 20 yards and they are in turn regarding the 2 hundred meters towards the the southern area of of PFV 231 (Profile 1a). Decorated Wilderness Sandstone step three, and that quickly underlies all of the around three localities, are stratigraphically

۴۰–fifty m over the foot of the Petrified Forest Affiliate (Figure 1b; Parker & ), and you can means a sheet sandstone placed by the perennial disperse in good large sinuosity river route (Johns, 1988 ). PFV 297 and you may PFV 414 exists somewhat large about sequence than PFV 231 (Parker & ).