Table 2. Morphological comparisons.

Morphological comparisons of selected traits among Pattonimus gen. nov. and other related oryzomyines.

	Pattonimus	Nephelomys1	Mindomys2	Tanyuromys3
Dorsal hindfeet condition	Naked-looking	Scarcely covered by short hairs	Densely covered by short hairs	Scarcely covered by short hairs
Rostrum	Moderate	Long	Moderate	Short
Zygomatic notch	Shallow	Well defined	Indistinct	Shallow
Lacrimal	Small	Medium	Medium	Small
Interorbit	Anteriorly convergent, with sharp margins	“hourglass,” with rounded margins	Anteriorly convergent, with beaded margins	Anteriorly convergent, with sharp margins
Antorbital bridge	Broad	Narrow	Broad	Narrow
Molars relative size	Medium	Small	Large	Large
Incisive foramen relative size	Medium	Small	Medium	Medium
Incisive foramen maxillary septum	Narrow	Narrow	Narrow	Broad
Palate	Short	Long	Short	Short
Posterolateral palatal pits	Scarce	Numerous	Scarce	Scarce
Basioccipital	Long	Long	Short	Short
Zygomatic plate upper border	Not patent	Patent	Not patent	Not patent
Squamosal fenestra	Small	Well-developed	Absent	Absent
Lacerate foramen	Scarcely ossified	Scarcely ossified	Scarcely ossified	Well-ossified
Alisphenoid strut	Present	Unilaterally present	Absent	Absent
Squamosal ridge	Absent	Present	Barely present	Present
Sphenofrontal foramen	Covered by alar fissure	Not covered by alar fissure	Covered by alar fissure	Absent
Molar design	Incipiently laminate	Not laminated, bulbous	Not laminated, bulbous	Not laminated, bulbous
Enamel borders lophs and lophids	Straight	Straight	Straight	Crenulate
M1 procingulum	Compressed without flexus	Broad with flexus	Broad without flexus	Broad with flexus and fossete
M1–M2 anteroloph	Small or absent	Patent	Patent	Patent
M3 size relative M2	M3 ≪ M2	M3 < M2	M3 < M2	M3 < M2
M3 shape	Subtriangular, compressed	Not compressed	Not compressed	Not compressed
M1 procingulum	Compressed, without flexid	Broad, with flexid	Broad, with fossetid	Broad, with fossetid
M1 anterior murid	Absent	Present	Present	Present
Mesolophids M1–M2	Absent	Present	Present	Present
Angular process	Medium	Medium	Short and broad	Short and broad
Number of ribs	12	12	?	12 or 13

Notes:

¹Character states are those of Nephelomys albigularis; other species currently classified under the genus may possess different attributes.

²Character states are those of Mindomys hammondi.

³Character states are those of Tanyuromys thomasleei; other species currently classified under the genus may possess different attributes.