Skull,1,Premaxilla: ventral margin aligned anteroposteriorly in lateral view (0); anteroventrally in lateral view (1).
Skull,2,Premaxilla: alary process absent (0); alary process present on posterodorsal process (1).
Dentition,3,"Premaxillary dentition: first tooth relatively small relative to maxillary caniniform (0); subequal to maxillary caniniform (1). In taxa lacking maxillary caniniforms, state 1 applies when the first premaxillary tooth is the largest marginal tooth present."
Skull,4,Maxilla: relatively straight (0); posterior end flexed laterally (1).
Dentition,5,Maxilla: posterior-most tooth positioned at level of posterior margin of orbit (0); positioned more anteriorly (1).
Dentition,6,"Maxillary dentition: tooth stations number 30 teeth or more (0); 18–26 teeth (1); 14–17 teeth (2); 13 or less teeth (3). For multiple-rowed taxa, only those teeth with unobstructed profiles when viewed laterally are considered."
Dentition,7,"Teeth on maxillary dental field: none (0); less than 40 (1); 40 or more (2). Definition modified from Reisz et al. (2011 Reisz, R. R., Liu, J., Li, J. and Müller, J. 2011. A new captorhinid reptile, Gansurhinus qingtoushanensis gen. et sp. nov., from the Permian of China. Naturwissenschaften, 98: 435–441. ) for clarity."
Dentition,8,Maxillary caniniform teeth: present (0); absent (1).
Dentition,9,Number of tooth rows in the upper jaw: one (0); two to four (1); five (2); six or more (3).
Dentition,10,Marginal dentition: ‘cheek’ teeth recurved (0); chisel-shaped (1); bulbous and ogival (2); bulbous at base and conical above (3).
Dentition,11,Maxilla: double row of teeth extend far anteriorly on tooth row absent (0); present (1).
Dentition,12,"Dental tooth wear: absent (0); present, modest (1); present, saddle-shaped (2)."
Skull,13,Lacrimal: suture with jugal small (0); well-developed (1).
Skull,14,Nasolacrimal suture: straight (0); interdigitating (1).
Skull,15,"Snout: broad, equal to or greater than 35% of skull length (0); narrow, equal to or less than 25% of skull length (1)."
Skull,16,Antorbital/cheek region: mainly formed by lacrimal and prefrontal (0); mostly formed by lacrimal due to a strong dorsal expansion of the bone (1).
Skull,17,"Prefrontal: anterior process short and tall, approximately equal to the posterodorsal process in anteroposterior length (0); long and narrow, approximately twice the anteroposterior length of the posterodorsal process (1)."
Skull,18,"Frontal: anterior process short, less than 40% of the frontal sagittal length (0); long, approximately 55% of the frontal sagittal length (1)."
Skull,19,"Jugal: subtemporal process dorsoventrally low, equal to or less than 25% of skull height through orbital midpoint (0); dorsoventrally deep, at least 40% of skull height through orbit (1)."
Skull,20,Jugal: anterior extent reaches beyond anterior orbital margin (0); not (1).
Skull,21,Jugal: postorbital extent shorter than remaining anterior extent (0); equal or longer (1).
Skull,22,"Quadratojugal: anteroposteriorly elongate (0); short, not extending anteriorly beyond midpoint of postorbital margin (1)."
Skull,23,Quadratojugal: acuminate anteriorly (0); square-tipped anteriorly (1).
Skull,24,Quadratojugal: posteriorly straight or decreasing in height (0); expanded dorsally (1).
Skull,25,Quadratojugal: maximum height approximately equal to one-third the height of squamosal or less (0); nearly equal to half of squamosal height (1).
Skull,26,Postorbital cheek: relatively straight (0); moderately expanded laterally (1); greatly expanded laterally (2).
Skull,27,Parietal: does not strongly project between postfrontal and postorbital (0); distinct anterolateral process present that partially separates postfrontal and postorbital (1).
Skull,28,Pineal foramen: positioned at midpoint of interparietal suture (0); anterior to midpoint of interparietal suture (1); posterior to midpoint of interparietal suture (2).
Skull,29,"Sculpturing: skull surface relatively smooth, with only small honeycombing pits or grooves (0); with pits and grooves with notably larger, randomly positioned pits on posterior skull table (1)."
Skull,30,"Supratemporal: obliquely oriented into anteromedial direction, thereby lying within a facet of the parietal (0); positioned mediolaterally at the posterior edge of the parietal (1)."
Skull,31,"Supratemporal: small, slender element (0); large, contributing to skull table (1)."
Skull,32,Supratemporal-postparietal contact: tenuous or absent (0); well developed (1).
Skull,33,"Postparietal: contacts mate fully along height (0); dorsally only, postparietals separated slightly ventrally by supraoccipital (1)."
Skull,34,Postparietal: transversely short with tabular present (0); transversely elongate with tabular absent (1).
Skull,35,"Postparietal: contribution to skull table absent or forms only narrow edge (0); contribution large, forming sculptured posterior portion of skull table (1)."
Skull,36,Skull table occipital margin: embayed bilaterally (0); straight (1); with single median embayment (2).
Dentition,37,Vomer: denticulate (0); edentulous (1).
Palate,38,"Vomer-pterygoid contact: extensive, at least 50% median border of vomer (0); short, no more than 33% median border of vomer (1)."
Dentition,39,Palatine: denticulate (0); edentulous (1).
Palate,40,"Jugal/ectopterygoid: ectopterygoid present and alary process absent (0); ectopterygoid absent and alary process present, but no higher than the midpoint of the suborbital process of the jugal and distinct from the orbital margin (1); ectopterygoid absent and alary process present and positioned dorsally on the medial surface of the jugal, flush with orbital margin (2)."
Dentition,41,Dentition on palatal ramus of pterygoid: present (0); greatly reduced or absent (1).
Dentition,42,Pterygoid: transverse flange dentition consists of shagreen of denticles (0); at least one row of functional teeth (1); absent (2).
Palate,43,Pterygoid: transverse flange broad-based and distinctly angular in ventral view (0); narrow and tongue-like in ventral view (1).
Palate,44,Suborbital foramen: absent (0); present (1); anteroposteriorly elongate (2).
Palate,45,Parasphenoid: cultriform process extends anteriorly (0); extends slightly dorsally at roughly 15° to the basal plane (1); extends anterodorsally at more than 45° to the basal plane (2).
Dentition,46,Parasphenoid: denticulate (0); edentulous (1).
Palate,47,Parasphenoid: deep ventral groove absent (0); present (1) between cristae ventrolateralis.
Palate,48,"Parasphenoid: posterolateral wing narrow, meets narrow head of stapes (0); wing broad, meets large head of stapes, in an elongate, nearly parasagittal suture (1)."
Skull,49,"Opisthotic: paroccipital process long, extending near to medial edge of squamosal (0); process short, extending only slightly beyond body of opisthotic (1)."
Skull,50,Paroccipital process: broad (0); narrow (1).
Skull,51,Stapes: distal process short (0); elongate (1).
Skull,52,Supraoccipital: slopes anterodorsally (0); aligned vertically or slopes posterodorsally (1).
Skull,53,Supraoccipital: lateral ascending processes account for half or less height of bone (0); lateral ascending processes account two-thirds or more height of the bone (1).
Skull,54,Occipital condyle: at level of quadrate condyles (0); immediately anterior to condyles (1).
Skull,55,Exoccipital: lateral process on dorsal ramus absent (0); present (1).
Dentition,56,"Dentary: teeth isodont (0), caniniform region present anteriorly (1); caniniform tooth present anteriorly with caniniform region absent (2)."
Dentition,57,Dentary: first tooth oriented mainly vertically (0); leans strongly anteriorly (1).
Mandible,58,Mandibular ramus: relatively straight in ventral view (0); sigmoidal in ventral view (1).
Mandible,59,"Mandibular ramus: narrow, 8% or less of total jaw length (0); broad, no less than 14% of total jaw length (1)."
Mandible,60,Mandibular ramus: posterior end rectilinear in lateral view (0); acuminate in lateral view (1).
Mandible,61,Mandibular ramus: lateral shelf absent (0); lateral shelf present below coronoid process (1).
Mandible,62,Coronoid: anterior process short (0); elongate (1).
Mandible,63,"Meckelian foramen: small, anteroposterior length roughly 9% or less of total jaw length (0); large, anteroposterior length greater than or equal to 14% of total jaw length (1)."
Mandible,64,"Coronoid: posterodorsal process slender, forms dorsal-most quarter of lateral wall of adductor fossa (0); posterodorsal process deep, forms dorsal-most third of lateral wall of adductor fossa (1)."
Mandible,65,Retroarticular process: absent (0); present and broader transversely than long (1); present and longer anteroposteriorly than broad (2).
Postcranium,66,"Dorsal neural arches: narrow (0); lateral expansion present (1); exaggerated lateral expansion with swelling present (2). Modified slightly from Reisz et al. (2011 Reisz, R. R., Liu, J., Li, J. and Müller, J. 2011. A new captorhinid reptile, Gansurhinus qingtoushanensis gen. et sp. nov., from the Permian of China. Naturwissenschaften, 98: 435–441. )."
Postcranium,67,Neural spines of dorsal vertebrae: height or shape alternation present (0); absent (1).
Postcranium,68,Anterior dorsal centra: not strongly ventrolaterally constricted (0); strongly ventrolaterally constricted (1).
Postcranium,69,Sacral ribs: first sacral rib larger than second rib (0); both ribs of roughly equal size (1).
Postcranium,70,Ilium: iliac blade expanded dorsally (0); narrow dorsally (1).
Postcranium,71,"Stylo- and zeugopodium: shaft massive and with proximal and distal heads significantly expanded, resulting in an overall stout impression (0); shaft slender and heads only moderately expanded (1)."
Postcranium,72,Humerus: supinator process not parallel to shaft (0); parallel (1); supinator process absent (2).
Postcranium,73,Manus and pes: elements short and broad (0); long and slender (1).
Postcranium,74,Fourth metatarsal: less than half the length of tibia (0); more than half the length of tibia (1).
Postcranium,75,First metacarpal: more than half the length of fourth metacarpal (0); less than half the length of fourth metacarpal (1).