2 GEOLOGICAL Function

None Parker et al. ( 2005 ) neither Take a look ainsi que al. ( 2005 ) tried an excellent phylogenetic data out-of Roentgen. callenderi based on the the newest skeletal topic. Yet not, both groups detailed multiple top features of the hindlimb that were unambiguous synapomorphies away from Pseudosuchia. Parker ainsi que al. ( 2005 ) hypothesized a potential cousin-class experience of aetosaurs, listing this new morphological similarities of one’s squamosal and paramedian osteoderms. An equivalent standing was suggested because of the Seem et al. ( 2005 ) centered on unspecified profile claims of tarsus and osteoderms. Brusatte ainsi que al. ( 2010 ) provided Roentgen. callenderi within analysis of very early archosaur relationship, programming throughout the authored rates and you will descriptions away from Parker mais aussi al. ( 2005 ) and you may Search et al. ( 2005 ). That study recovered R. callenderi because cousin taxon toward very early-diverging suchian clade Ornithosuchidae. ( 2011 ) recovered Roentgen. callenderi within the a well-served condition because sister taxon so you’re able to aetosaurs, an end result supported by more recent training (e.grams., Butler et al., 2014 ; ; Nesbitt & Butler, 2013 ; Nesbitt et al., 2014 ; Nesbitt mais aussi al., 2020 ; Nesbitt, Stocker, mais aussi al., 2018 ).

Which sum fully means the new osteology away from Roentgen. callenderi based on a minimum of 12 people (according to femora count) out-of PEFO plus three better-managed associated limited skeletons collected ranging from 2005 and you may 2015, brings osteohistological perspective, and covers brand new taxon’s pros to possess understanding early suchian evolution.

dos.1 Stratigraphic position

Which malfunction from Roentgen. callenderi are predominantly according to point away from several localities on Chinle Development off Petrified Tree National Playground (PEFO), Arizona, All of us (Profile 1; find Systematic Paleontology). The top Triassic Chinle Formation in this field comprises mainly fluvial and you may floodplain strata out-of alternating claystones, siltstones, sandstones, and you will conglomerates (Billingsley, 1985 ; Heckert & Lucas, 2002a ; ). Brand new Chinle Creation regarding the Petrified Tree Federal Park urban area saves well-understood traditional assemblages regarding plants (palynomorphs, departs, wood), invertebrates, and you can vertebrates (e.g., Ash, 2005 ; Baranyi et al., 2018 ; A beneficial, 1998 ; Irmis, 2005 ; Litwin, Navigate, & Ash, 1991 ; Parker, 2005b , 2006 ; Reichgelt mais aussi al., 2013 ). Really low-dentigerous and you can non-osteoderm specimens out of R. callenderi out-of PEFO, along with those people revealed right here, have been discovered instantly more than Coated Wilderness Sandstone step 3 (sensu Billingsley, 1985 ; Lithodendron Clean Bed sensu Heckert & Lucas, 2002a ) among an element of the Petrified Tree Representative (sensu Woody, 2006 ) of one’s top area of the Chinle Development (Heckert & Lucas, 2002a ; Irmis, 2005 ; Padian, 1990 ; Parker, 2005b , 2006 ; Parker et al., 2005 ; Parker & ). Separated pearly whites of Roentgen. callenderi was recovered regarding microvertebrate assemblages out of reduced in the newest Chinle Creation at PEFO, stretching the latest stratigraphic listing of that it taxon with the Sonsela User and you can highest Blue Mesa Representative (discover Logical Paleontology).

The three chief localities that introduced the newest specimens off Roentgen. callenderi discussed here (Data S1) may be cupid indir the Revueltosaurus Quarry (PFV 297), Revueltosaurus Quarry SW (PFV 414), in addition to Giving Web site (PFV 231). These sites can be found since the paleosols for the a loaded fluvial series inside the midst of the brand new Petrified Tree Member (Atchley mais aussi al., 2013 ; Loughney ainsi que al., 2011 ; Parker mais aussi al., 2005 ; Parker & ). PFV 297 and you will PFV 414 is split spatially of the 20 meters consequently they are in turn on the 2 hundred m toward the southern area of of PFV 231 (Profile 1a). Decorated Wasteland Sandstone step three, which quickly underlies all of the around three localities, are stratigraphically

40–fifty yards over the base of the Petrified Tree Representative (Shape 1b; Parker & ), and you may stands for a layer sandstone placed from the perennial flow inside a good large sinuosity river channel (Johns, 1988 ). PFV 297 and you will PFV 414 are present some highest regarding sequence than PFV 231 (Parker & ).