dos GEOLOGICAL Setting
None Parker mais aussi al. ( 2005 ) nor Have a look et al. ( 2005 ) tried good phylogenetic analysis off Roentgen. callenderi based on the the newest skeletal thing. not, one another groups noted numerous popular features of brand new hindlimb which were unambiguous synapomorphies regarding Pseudosuchia. Parker ainsi que al. ( 2005 ) hypothesized a possible sibling-category reference to aetosaurs, listing the brand new morphological parallels of the squamosal and you can paramedian osteoderms. The same reputation are advised by the Take a look ainsi que al. ( 2005 ) considering unspecified character says of one’s tarsus in addition to osteoderms. Brusatte mais aussi al. ( 2010 ) included Roentgen. callenderi in their studies away from early archosaur matchmaking, coding on the typed figures and you may descriptions of Parker et al. ( 2005 ) and you may Hunt mais aussi al. ( 2005 ). One analysis retrieved Roentgen. callenderi given that sister taxon toward early-diverging suchian clade Ornithosuchidae. ( 2011 ) retrieved Roentgen. callenderi when you look at the a highly-offered condition just like the aunt taxon to aetosaurs, an effect backed by more recent studies (age.grams., Butler et al., 2014 ; ; Nesbitt & Butler, 2013 ; Nesbitt mais aussi al., 2014 ; Nesbitt mais aussi al., 2020 ; Nesbitt, Stocker, ainsi que al., 2018 ).
This contribution fully means brand new osteology from Roentgen. callenderi centered on at least 12 anyone (based on femora count) out-of PEFO and three really-maintained relevant partial skeletons gathered ranging from 2005 and you can 2015, will bring osteohistological perspective, and you will covers this new taxon’s characteristics getting knowledge early suchian evolution.
dos.1 Stratigraphic updates
This malfunction out-of R. callenderi was mostly considering situation out of multiple localities in the Chinle Development off Petrified Forest National Playground (PEFO), Arizona, Us (Figure step 1; find Scientific Paleontology). The top of Triassic Chinle Development in this region comprises mostly fluvial and you will floodplain strata from changing claystones, siltstones, sandstones, and conglomerates (Billingsley, 1985 ; Heckert & Lucas, 2002a ; ). Brand new Chinle Formation from the Petrified Forest National Park area preserves well-identified fossil assemblages of plants (palynomorphs, actually leaves, wood), invertebrates, www.datingranking.net/tr/aisle-inceleme and you can vertebrates (e.g., Ash, 2005 ; Baranyi ainsi que al., 2018 ; An excellent, 1998 ; Irmis, 2005 ; Litwin, Traverse, & Ash, 1991 ; Parker, 2005b , 2006 ; Reichgelt ainsi que al., 2013 ). Very low-dentigerous and you may low-osteoderm specimens out-of Roentgen. callenderi away from PEFO, and additionally men and women explained here, have been found instantly over Painted Wasteland Sandstone step 3 (sensu Billingsley, 1985 ; Lithodendron Clean Bed sensu Heckert & Lucas, 2002a ) around part of the Petrified Tree Member (sensu Woody, 2006 ) of your own top a portion of the Chinle Creation (Heckert & Lucas, 2002a ; Irmis, 2005 ; Padian, 1990 ; Parker, 2005b , 2006 ; Parker mais aussi al., 2005 ; Parker & ). Isolated teeth regarding Roentgen. callenderi had been retrieved out-of microvertebrate assemblages away from lower in the fresh Chinle Formation within PEFO, extending new stratigraphic range of so it taxon on the Sonsela Member and you can best Bluish Mesa User (get a hold of Health-related Paleontology).
The three main localities one produced the fresh new specimens out-of R. callenderi explained here (Data S1) certainly are the Revueltosaurus Quarry (PFV 297), Revueltosaurus Quarry SW (PFV 414), and the Giving Site (PFV 231). Web sites exist since the paleosols when you look at the a loaded fluvial series when you look at the the middle of brand new Petrified Tree Affiliate (Atchley mais aussi al., 2013 ; Loughney mais aussi al., 2011 ; Parker mais aussi al., 2005 ; Parker & ). PFV 297 and PFV 414 is split spatially because of the 20 meters and generally are subsequently regarding 200 m on the southern part of out of PFV 231 (Shape 1a). Coated Wilderness Sandstone step 3, and therefore instantly underlies all the three localities, was stratigraphically
40–fifty meters over the root of the Petrified Forest Member (Profile 1b; Parker & ), and you will represents a layer sandstone transferred by perennial flow during the an excellent highest sinuosity river route (Johns, 1988 ). PFV 297 and you may PFV 414 occur quite high regarding the series than PFV 231 (Parker & ).