TABLE 3. Comparison of suborbital fossa development and infraorbital foramen in Plesiotypotherium minus and other mesotheriines (based on Croft et al. 2004).

	Taxon	Specimen	Suborbital fossa	Infraorbital foramen (mm)	M1 size (mm)	Relative size of Infraoribital foramen
	Altitypotherium paucidens	SGOPV 4038	Shallow	10.5 x 5.5	12.5 x 8.6	0.42
	Eutypotherium chico	SGOPV 5157	Shallow	4.0 x 3.5	9.5 x 6.4	0.18
	Eutypotherium lemannnitschei	MLP 12-1701	Shallow	7.5 x 5.4	14.6 x 10.0	0.22
	Eutypotherium superans	MACN 11079	Shallow	5.5 x 4.1	14.1 x 10.0	0.13
	Caraguatypotherium munozi	SGOPV 4004	Shallow	6.5 x 4.9	16.5 x 10.0	0.15
	Typotheriopsis silveyrai	MLP 36-xI-10-2	Deep	6.6 x 5.7	16.9 x 11.4	0.15
	Typotheriopsis sp.	FMNH P14477	Deep	7.5x 6.2	22.5 x 14.5	0.11
	Plesiotypotherium' minus	UF 133803	Deep	4.34 x 4.1	11.0 x 8.4	0.19
	?Pseudotypotherium sp.	MACN 8010	Deep	14.2 x 12.4	23.8 x 11.0	0.53
	?Pseudotypotherium sp.	MACN 1111	Deep	12.2 x 7.7	19.2 x 10.5	0.37
	Mesotherium cristatum	MACN 2036	Absent	3.9 x 3.0	21.8 x 9.8	0.04
	Mesotherium pachygnathum	MACN 1665	Absent?	9.4 x 5.8	24.4 x 11.4	0.15
	Mesotherium ?ugustirostrum	MACN 6040	Absent	5.1 x 3.5	23.6 x 11.1	0.05