2 GEOLOGICAL Setting
Neither Parker ainsi que al. ( 2005 ) neither Seem mais aussi al. ( 2005 ) attempted a good phylogenetic studies off Roentgen. callenderi according to research by the the brand new skeletal matter. However, one another organizations listed several options that come with brand new hindlimb that were unambiguous synapomorphies out-of Pseudosuchia. Parker et al. ( 2005 ) hypothesized a possible aunt-class relationship with aetosaurs, noting the newest morphological similarities of your squamosal and you will paramedian osteoderms. An equivalent standing is actually suggested by Search mais aussi al. ( 2005 ) centered on unspecified character says of tarsus and also the osteoderms. Brusatte mais aussi al. ( 2010 ) provided Roentgen. callenderi within investigation from early archosaur relationships, coding on authored data and meanings off Parker ainsi que al. http://www.datingranking.net/tr/connexion-inceleme ( 2005 ) and you may Appear mais aussi al. ( 2005 ). You to definitely study retrieved R. callenderi while the sibling taxon into the very early-diverging suchian clade Ornithosuchidae. ( 2011 ) recovered Roentgen. callenderi in a highly-served status just like the brother taxon so you can aetosaurs, an end result supported by more recent education (elizabeth.g., Butler mais aussi al., 2014 ; ; Nesbitt & Butler, 2013 ; Nesbitt et al., 2014 ; Nesbitt mais aussi al., 2020 ; Nesbitt, Stocker, ainsi que al., 2018 ).
That it contribution totally means the brand new osteology of Roentgen. callenderi centered on a minimum of a dozen people (considering femora number) regarding PEFO together with about three really-managed associated partial skeletons obtained anywhere between 2005 and you may 2015, brings osteohistological context, and you may discusses the fresh new taxon’s characteristics to have information early suchian progression.
2.step 1 Stratigraphic condition
It malfunction of Roentgen. callenderi is actually mainly according to material off several localities regarding Chinle Creation of Petrified Tree National Playground (PEFO), Arizona, All of us (Shape step 1; pick Medical Paleontology). Top of the Triassic Chinle Development here constitutes mostly fluvial and you may floodplain strata out-of switching claystones, siltstones, sandstones, and conglomerates (Billingsley, 1985 ; Heckert & Lucas, 2002a ; ). New Chinle Development on the Petrified Forest Federal Playground area conserves well-known traditional assemblages out-of herbs (palynomorphs, actually leaves, wood), invertebrates, and you can vertebrates (age.grams., Ash, 2005 ; Baranyi ainsi que al., 2018 ; A, 1998 ; Irmis, 2005 ; Litwin, Traverse, & Ash, 1991 ; Parker, 2005b , 2006 ; Reichgelt mais aussi al., 2013 ). Very low-dentigerous and you can low-osteoderm specimens out of Roentgen. callenderi from PEFO, and additionally those people revealed right here, have been discovered immediately a lot more than Coated Desert Sandstone step three (sensu Billingsley, 1985 ; Lithodendron Clean Bed sensu Heckert & Lucas, 2002a ) in between part of the Petrified Forest Member (sensu Woody, 2006 ) of one’s higher the main Chinle Development (Heckert & Lucas, 2002a ; Irmis, 2005 ; Padian, 1990 ; Parker, 2005b , 2006 ; Parker et al., 2005 ; Parker & ). Isolated white teeth out of R. callenderi was in fact recovered regarding microvertebrate assemblages from lower in the new Chinle Creation from the PEFO, extending new stratigraphic variety of so it taxon on the Sonsela Member and you may highest Blue Mesa Representative (come across Clinical Paleontology).
The three chief localities you to definitely brought the fresh new specimens out-of R. callenderi revealed here (Data S1) will be Revueltosaurus Quarry (PFV 297), Revueltosaurus Quarry SW (PFV 414), therefore the Providing Website (PFV 231). Those sites can be found given that paleosols for the a loaded fluvial sequence inside the midst of the fresh new Petrified Tree Associate (Atchley mais aussi al., 2013 ; Loughney ainsi que al., 2011 ; Parker mais aussi al., 2005 ; Parker & ). PFV 297 and PFV 414 try separated spatially by 20 meters as they are therefore on 200 yards into the southern part of regarding PFV 231 (Shape 1a). Painted Wilderness Sandstone step 3, hence quickly underlies most of the three localities, is stratigraphically
40–fifty yards over the root of the Petrified Tree Representative (Figure 1b; Parker & ), and represents a layer sandstone placed from the recurrent flow in the an effective large sinuosity lake station (Johns, 1988 ). PFV 297 and you will PFV 414 exists a bit highest from the sequence than just PFV 231 (Parker & ).