Rooting Around the Eutherian Family Tree: the Origin and Relations of the Taeniodonta

Abstract

Placing early groups into the overall phylogeny of eutherian mammals can be challenging, particularly when the group does not have extant members. We investigated the relationships of the Taeniodonta, an extinct group from the Late Cretaceous through Paleogene of North America. This group has a few purported close relatives, including Cimolestes, Procerberus, and Alveugena, that may form a sequence of ancestors and descendants. The leading hypothesis is that Procerberus gave rise to taeniodonts through Alveugena. We test this hypothesis and analyze relations to known stem and crown Eutheria to determine the place of taeniodonts in eutherian phylogeny. Cladistic analyses were performed using previously published characters and datasets, namely a taeniodont/cimolestid specific dataset and a reanalysis of Wible and colleagues (2009), with added taxa for both. Our studies suggest that taeniodonts arose from Cimolestes through Alveugena, that Procerberus is more distantly related to taeniodonts, and that taeniodonts and their relatives are stem eutherians. We diagnose the Taeniodonta based on these analyses. Other Paleogene groups, especially those allied with Cimolestes such as tillodonts and pantolestans, merit further study. Our findings indicate that stem eutherians such as the Taeniodonta, in addition to crown eutherians, continued to diversify during the Paleogene.

Appendices

Appendix 1: Cimolestid Versus Palaeoryctid Analysis- Characters and Matrix from Analysis

Characters

These characters are the same as those used in Rook et al. (2010) and Rook and Hunter (2011). The characters appeared originally either in Schoch (1986) as uncoded lists or in Eberle (1999) coded for Cimolestes, Procerberus formicarum, P. grandis, Alveugena, and Onychodectes only. We cite below the source for each character. All taxa were coded by the senior author for characters modified from Schoch (1986). Similarly, all taxa, other than those listed above, were coded by the senior author for the characters from Eberle (1999). Additive characters are marked below with an asterix (*) and follow Eberle (1999), Rook et al. (2010), and Rook and Hunter (2011) in treating these characters as additive, based on the character states needing to progress through the central state (for instance, “medium”) before being either extreme. Premolars again are numbered assuming an ancestral count of five (e.g., Wible et al. 2009).

• 1. Upper molar protocone size (Schoch 1986) *

  • 0 = small

  • 1 = moderate

  • 2 = large

• 2. Upper molar conule size (Schoch 1986)

  • 0 = small

  • 1 = large

  • 2 = absent

• 3. Placement of conules on upper molars (modified from Eberle 1999)

  • 0 = labial

  • 1 = lingual

• 4. Upper molar paracone size (Schoch 1986) *

  • 0 = small

  • 1 = moderate

  • 2 = large

• 5. Stylar margin on upper molars (Eberle 1999) *

  • 0 = large, inflated stylar lobes; forward-projecting, parastylar lobe extends labially beyond, and often hooks around, metastylar lobe on tooth directly in front of it; stylar lobes appear largest on M2

  • 1 = para- and metastylar lobes relatively smaller than those of Cimolestes and Procerberus formicarum, but still relatively inflated; parastylar lobe is not hook-like, does not project anteriorly, and projects only slightly more labially (if at all) beyond metastylar lobe of tooth directly anterior to it

  • 2 = small, weak, uninflated stylar lobes; stylar shelves very narrow to absent; M2 stylar lobes subequal in size to those of other molars

• 6. Upper molar metacone size (Schoch 1986) *

  • 0 = small

  • 1 = moderate

  • 2 = large

• 7. Lingual cingula on upper molars (Eberle 1999)

  • 0 = present

  • 1 = absent

• 8. Lower molar trigonid height (modified from Eberle 1999) *

  • 0 = trigonid noticeably higher than talonid

  • 1 = trigonid only slightly higher than talonid

  • 2 = trigonid equal in height to talonid

• 9. Lower first molar trigonid width (modified from Eberle 1999)

  • 0 = trigonid wider than talonid

  • 1 = trigonid equal in width to talonid

  • 2 = width variable within taxon

• 10. Lower second molar trigonid width (modified from Eberle 1999)

  • 0 = trigonid wider than talonid

  • 1 = trigonid equal in width to talonid

  • 2 = width variable in taxon

• 11. Lower third molar trigonid width (modified from Eberle 1999)

  • 0 = trigonid wider than talonid

  • 1 = trigonid equal in width to talonid

  • 2 = width variable in taxon

• 12. Lower molar paraconids versus metaconids (Schoch 1986)

  • 0 = not equal

  • 1 = subequal

• 13. Molar hypsodonty (modified from Eberle 1999) *

  • 0 = absent

  • 1 = present

  • 2 = hypselodonty

• 14. P4 morphology (modified from Eberle 1999) *

  • 0 = triangular

  • 1 = submolariform

  • 2 = molariform

• 15. P5 morphology (modified from Eberle 1999) *

  • 0 = triangular

  • 1 = submolariform

  • 2 = molariform

• 16. p5 talonid heel (Schoch 1986) *

  • 0 = small

  • 1 = moderate

  • 2 = well developed

• 17. P5 parastyle (modified from Eberle 1999) *

  • 0 = absent

  • 1 = incipient

  • 2 = small

  • 3 = well developed

• 18. P5 stylocone (modified from Eberle 1999) *

  • 0 = absent

  • 1 = incipient

  • 2 = small

  • 3 = well developed

• 19. P5 metastyle (modified from Eberle 1999) *

  • 0 = absent

  • 1 = incipient

  • 2 = small

  • 3 = well developed

• 20. Lower molar paraconids (Schoch 1986) *

  • 0 = small

  • 1 = moderate

  • 2 = large

• 21. P1 (Schoch 1986)

  • 0 = present

  • 1 = absent

• 22. p5 morphology (Schoch 1986) *

  • 0 = nonmolariform

  • 1 = submolariform

  • 2 = molariform

• 23. M1 and M2 mesostyle (Schoch 1986)

  • 0 = absent

  • 1 = small

  • 2 = moderate

  • 3 = well developed

• 24. Premolars set obliquely (Schoch 1986)

  • 0 = no

  • 1 = yes

• 25. Lower canines (Schoch 1986) *

  • 0 = small

  • 1 = moderate

  • 2 = large

• 26. Upper incisor number (Schoch 1986) *

  • 0 = 3

  • 1 = 2

  • 2 = 1

• 27. Lower incisor number (Schoch 1986) *

  • 0 = 3

  • 1 = 2

  • 2 = 1

• 28. p4 morphology (Schoch 1986) *

  • 0 = nonmolariform

  • 1 = submolariform

  • 2 = molariform

• 29. Lower canine root (Schoch 1986) *

  • 0 = shallow

  • 1 = deep

  • 2 = tending towards rootlessness

  • 3 = rootless

• 30. Bilophodont molars (Schoch 1986)

  • 0 = absent

  • 1 = present

• 31. Transverseness of upper molars (Eberle 1999) *

  Relative Transverse Width (RTW) = Maximum Transverse Width/Anteroposterior length

  • 0 = transverse (RTW of M1 > 1.30)

  • 1 = less transverse (1.30 > RTW of M1 > 1.20)

  • 2 = weakly to nontransverse (RTW of M1 < 1.20)

• 32. Development of molar ectoflexus (Eberle 1999) *

  • 0 = pronounced and deep, particularly on M2

  • 1 = small, shallow indentation

  • 2 = virtually absent, resulting in a relatively straight stylar shelf

• 33. Size of M2 relative to M1 (Eberle 1999) *

  • 0 = M2 noticeably larger than M1

  • 1 = M2 shorter but more transverse than M1

  • 2 = M2 subequal in size to, or slightly smaller than, M1

• 34. Upper molar lingual length (modified from Eberle 1999)

  • 0 = not pronounced

  • 1 = pronounced

• 35. Metacrista on upper molars (modified from Eberle 1999) *

  • 0 = well developed

  • 1 = reduced

  • 2 = absent

• 36. Lower molar cingulids (Eberle 1999)

  • 0 = present

  • 1 = absent

• 37. Wear pattern on upper molars and premolars (Eberle 1999)

  • 0 = not pronounced over entire occlusal surface

  • 1 = pronounced over entire occlusal surface

Matrix

Protictis	1102000000010111303101101000100111110
Cimolestes	?10000000000000133300000???0000000000
Acmeodon	0202101000000012???111101??0?00010000
Aaptoryctes	2110001000000011000011000?00000010100
Palaeoryctes	22?20010000001113300?0001?00000010000
Didelphodus	0202000000000011202101001001000000000
Procerberus formicarum	010000000000022?333?0000???0001000100
Procerberus grandis	01001001000?0222333200001??0001000101
Alveugena	0?01110000?000002320000011?0001111101
Schowalteria	????0?11100?1002232000?021?1000001?11
Onychodectes	0101211122011011121200001000002221111
Conoryctella	2202221122201011232201102000201121111
Conoryctes	2202221120001121232011202110100221111
Huerfanodon	02122211200111?2???111302??0102221011
Schochia	1102201?????102?010???01??????02211?1
Wortmania	10-2201000?11002111100012220010211111
Psittacotherium	2212201220001112010001012221210221111
Ectoganus	2212221220211222010002012222312221211
Stylinodon	????2?12111?2222010?02?12122312221?11

Appendix 2: Stem/Crown Analysis- Characters, Matrix, and Full Figure from Analysis

Characters

Dental and cranial characters used from Wible et al. (2007, 2009). As in the original study, there are 408 dental, cranial, and postcranial characters. Characters coded here for Alveugena (A) and Schowalteria (S); all others can be found in Wible et al. (2009).

• 1. Teeth (A, S)

  • 0 = present

  • 1 = absent

• 2. Teeth (A, S)

  • 0 = differentiated into classes (incisors, canines, premolars, and molars) with enamel

  • 1 = simple peg-like without enamel

• 3. Number of postcanine tooth loci (A, S)

  • 0 = eight or more

  • 1 = seven

  • 2 = six

  • 3 = five or less

• 4. Upper diastema (A)

  • 0 = small, between incisors and canine

  • 1 = small, between canine and premolars

  • 2 = enlarged

  • 3 = absent

• 5. Lower diastema behind incisors (S)

  • 0 = absent or small

  • 1 = enlarged

  • Dentition – Incisors

• 6. Incisor shape (A)

  • 0 = root and crown are straight and continuous in length

  • 1 = a continuous curve

• 7. Number of upper incisors (A)

  • 0 = five

  • 1 = four

  • 2 = three

  • 3 = two

  • 4 = one

  • 5 = none

• 8. Number of lower incisors (S)

  • 0 = four

  • 1 = three

  • 2 = two, anterior position

  • 3 = one

  • 4 = none or posterior position(s) only

• 10. Anteriormost upper incisor size (S)

  • 0 = small, subequal to subsequent

  • 1 = enlarged

  • 2 = smaller than subsequent

• 14. Ultimate upper incisor (A, S)

  • 0 = in premaxilla

  • 1 = between maxilla and premaxilla

  • 2 = in maxilla

• 15. Anteriormost lower incisor size (S)

  • 0 = small, subequal to subsequent incisors

  • 1 = greatly enlarged

  • 2 = or tiny, smaller than subsequent

• 17. Procumbent anteriormost lower incisor (S)

  • 0 = absent

  • 1 = present

• 18. Anteriormost lower incisor root (S)

  • 0 = closed

  • 1 = open

• 21. Procumbent posterior lower incisor(s) (S)

  • 0 = absent

  • 1 = present

• 22. Staggered lower incisor (S)

  • 0 = absent

  • 1 = present

  • Dentition – Canine

• 23. Upper canine (A, S)

  • 0 = present, large

  • 1 = present, small

  • 2 = absent

• 24. Number of upper canine roots (A, S)

  • 0 = two

  • 1 = one

• 25. Lower canine (A, S)

  • 0 = present, large

  • 1 = present, small

  • 2 = absent

• 26. Number of lower canine roots (A, S)

  • 0 = two

  • 1 = one

• 27. Procumbent lower canine (A, S)

  • 0 = absent

  • 1 = present

  Dentition – Premolars

• 29. Number of premolars (A, S)

  • 0 = five or more

  • 1 = four

  • 2 = three

  • 3 = two

• 31. Tall, trenchant premolar (A, S)

  • 0 = ultimate premolar

  • 1 = penultimate premolar

  • 2 = absent

• 32. Procumbent first upper premolar (A, S)

  • 0 = absent

  • 1 = present

• 33. First upper premolar roots (A, S)

  • 0 = two

  • 1 = one

  • 2 = three

• 34. Diastema posterior to first upper premolar (S)

  • 0 = absent

  • 1 = present

• 36. Penultimate upper premolar protocone (A)

  • 0 = absent

  • 1 = small lingual bulge

  • 2 = with an enlarged basin

• 37. Penultimate upper premolar metacone (A)

  • 0 = absent

  • 1 = swelling

  • 2 = large

• 38. Penultimate upper premolar parastylar lobe (A, S)

  • 0 = absent or small

  • 1 = well developed

• 39. Penultimate upper premolar roots (A, S)

  • 0 = two

  • 1 = three

  • 2 = one

  • 3 = four

• 40. Ultimate upper premolar protocone (A)

  • 0 = absent or narrow cingulum

  • 1 = shorter than paracone

  • 2 = approaches paracone in height

• 41. Ultimate upper premolar metacone (A)

  • 0 = absent

  • 1 = swelling

  • 2 = large

• 42. Ultimate upper premolar para- and metastylar lobes (A, S)

  • 0 = absent or insignificant

  • 1 = subequal

  • 2 = parastylar lobe larger

  • 3 = metastylar lobe larger

• 43. Ultimate upper premolar precingulum (A)

  • 0 = absent

  • 1 = present

• 44. Ultimate upper premolar postcingulum (A)

  • 0 = absent

  • 1 = present, lower than protocone

  • 2 = present, level with protocone

• 46. Ultimate upper premolar size (occlusal surface) relative to first upper molar (A, S)

  • 0 = smaller or subequal

  • 1 = larger

• 47. First lower premolar orientation (A, S)

  • 0 = in line with jaw axis

  • 1 = oblique

• 48. First lower premolar roots (A, S)

  • 0 = two

  • 1 = one

• 49. Diastema separating first and second lower premolars (A, S)

  • 0 = absent (gap less than one tooth root for whichever is smaller of adjacent teeth)

    1 = present, subequal to one tooth-root diameter or more

• 52. Penultimate lower premolar paraconid (A, S)

  • 0 = indistinctive or absent

  • 1 = present and distinctive

• 53. Penultimate lower premolar metaconids (A, S)

  • 0 = absent

  • 1 = swelling

  • 2 = separate from protoconid

• 54. Penultimate lower premolar talonid cusps (A, S)

  • 0 = one

  • 1 = two

  • 2 = three

• 55. Ultimate lower premolar paraconid (A, S)

  • 0 = indistinctive or absent

  • 1 = distinctive but low

  • 2 = distinctive and high

• 56. Ultimate lower premolar metaconids (A, S)

  • 0 = absent

  • 1 = swelling

  • 2 = large

• 57. Ultimate lower premolar talonid (A, S)

  • 0 = narrower than anterior portion of crown

  • 1 = as wide as anterior portion of crown

• 59. Length of ultimate lower premolar to penultimate (A, S)

  • 0 = longer

  • 1 = equal to or less

• 60. Ultimate lower premolar anterolingual cingulid (S)

  • 0 = absent

  • 1 = present

  Dentition – Molars

• 61. Number of molars (A, S)

  • 0 = four or more

  • 1 = three

  • 2 = two

• 62. Size of molar series (A, S)

  • 0 = subequal

  • 1 = posterior increase

  • 2 = posterior decrease

• 63. Molar cusp form (A, S)

  • 0 = sharp, gracile

  • 1 = inflated, robust

  • 2 = crest-like

• 64. Upper molar shape (A, S)

  • 0 = as long as wide, or longer

  • 1 = wider than long (length more than 75 % but less than 99 % of width)

  • 2 = much wider than long (length less than 75 % of width)

• 65. Size (labiolingual width) of upper molar labial stylar shelf at maximum (A, S)

  • 0 = 50 % or more of total transverse width

  • 1 = less than 50 % but more than 25 %

  • 2 = less than 25 %

  • 2 = absent

• 66. Labial extent of parastylar and metastylar lobes (A, S)

  • 0 = parastylar lobe more labial

  • 1 = subequal

  • 2 = metastylar lobe more labial

  • 3 = lobes absent

• 67. M1 parastylar lobe relative to paracone (A, S)

  • 0 = parastylar lobe is anterolabial to paracone

  • 1 = parastylar lobe is anterior to paracone

• 68. Length of parastylar lobe (measured to stylocone or stylocone position) relative to total length on penultimate molar (A, S)

  • 0 = more than 30 %

  • 1 = less than 30 % but more than 20 %

  • 2 = 20 % or less

• 69. Preparastyle (A, S)

  • 0 = absent

  • 1 = present

• 70. Stylar cusp A (A, S)

  • 0 = subequal to larger than B

  • 1 = distinct, but smaller than B

  • 2 = vestigial to absent

• 71. Stylar cusp B relative to paracone (A, S)

  • 0 = smaller but distinctive

  • 1 = vestigial to absent

  • 2 = subequal

• 72. Stylar cusp C, mesostyle (A, S)

  • 0 = absent

  • 1 = present

• 73. Stylar cusp D (A, S)

  • 0 = absent

  • 1 = smaller or subequal to B

  • 2 = larger than B

• 74. Stylar cusp E (A)

  • 0 = directly lingual to D or D-position

  • 1 = distal to D

  • 2 = small to indistinct

• 75. Preparacingulum (A, S)

  • 0 = absent

  • 1 = interrupted between stylar margin and paraconule or paraconule position

  • 2 = continuous

• 76. Deep ectoflexus (A, S)

  • 0 = present only on penultimate molar

  • 1 = on penultimate and preceding molars

  • 2 = strongly reduced or absent

• 77. Metacone size relative to paracone (S)

  • 0 = noticeably smaller

  • 1 = slightly smaller

  • 2 = subequal or larger

  • 3 = absent or merged with paracone.

• 78. Metacone position relative to paracone (A)

  • 0 = labial

  • 1 = approximately at same level

  • 2 = lingual

• 79. Metacone and paracone bases (A)

  • 0 = adjoined

  • 1 = separated

• 80. Preparacrista (A)

  • 0 = strong, from side of paracone to stylocone

  • 1 = weak, from base of paracone, or absent

• 81. Cuspate preparacrista (A)

  • 0 = present

  • 1 = absent

• 82. Centrocrista (A)

  • 0 = straight

  • 1 = V-shaped

  • 2 = absent

• 83. Postmetacrista (A)

  • 0 = prominent, from side of metacone to metastyle

  • 1 = salient

  • 2 = weak, from base of metacone, or absent

• 84. Cuspate postmetacrista (A)

  • 0 = present

  • 1 = absent

• 87. Development of postvallum shear (A, S)

  • 0 = present but only by the first rank: postmetacrista

  • 1 = present, with the addition of a second rank (postprotocrista below postmetacrista) but the second rank does not reach labially below the base of the metacone

  • 2 = present, with second rank extending to metastylar lobe: metacingulum

  • 3 = absent

• 88. Paraconule (A)

  • 0 = weak or absent

  • 1 = prominent, closer to protocone

  • 2 = prominent, midway or closer to paracone

• 89. Metaconule (A)

  • 0 = weak or absent

  • 1 = prominent, closer to protocone

  • 2 = prominent, midway or closer to metacone

• 92. Protocone (A)

  • 0 = lacking

  • 1 = small, without trigon basin

  • 2 = with distinct trigon basin

• 93. Protocone antero-posterior expansion (A)

  • 0 = none, subequal to paracone

  • 1 = expanded, larger than paracone

• 94. Protocone procumbency (A, S)

  • 0 = absent

  • 1 = present

• 95. Degree of labial shift of protocone (distance from protocone apex to lingual border vs. total tooth width, in %) (A)

  • 0 = no labial shift (10 %–20 %)

  • 1 = moderate labial shift (21 %–30 %)

  • 2 = substantial labial shift (≥ 31 %)

• 97. Precingulum (A, S)

  • 0 = absent or weak

  • 1 = present

  • 2 = present, reaching labially passed the paraconule or paraconule position

• 98. Postcingulum (A, S)

  • 0 = absent or weak

  • 1 = present, lingual to metaconule or metaconule position

  • 2 = present, reaching labially passed metaconule or metaconule position

  • 3 = present, extending to labial margin

• 99. Hypocone on postcingulum (A, S)

  • 0 = absent

  • 1 = present, lower than protocone

  • 2 = present, subequal to protocone

• 100. Pre- and postcingulum (A, S)

  • 0 = separated

  • 1 = continuous lingually

• 101. Number of penultimate roots (A)

  • 0 = three

  • 1 = four

  • 2 = more

• 102. Number of roots on ultimate molar (A)

  • 0 = three

  • 1 = two

  • 2 = one

  • 4 = four or more

• 103. Lingual root position on upper molars (A)

  • 0 = supporting paracone

  • 1 = supporting trigon

• 104. Ultimate upper molar width relative to penultimate molar (A)

  • 0 = subequal

  • 1 = smaller

• 105. Metastylar lobe on ultimate molar (A)

  • 0 = absent

  • 1 = present

• 106. Paraconid (A, S)

  • 0 = present

  • 1 = absent

• 107. Paraconid height relative to metaconid (A, S)

  • 0 = shorter

  • 1 = subequal

  • 2 = taller

• 108. Paraconid on lingual margin (A, S)

  • 0 = absent

  • 1 = present

• 111. Trigonid configuration (A)

  • 0 = open, with paraconids anteromedial, paracristid-protocristid angle more than 50°

  • 1 = more acute, with paraconid more posteriorly placed, paracristid-protocristid angle between 36 and 49°

  • 2 = anteroposteriorly compressed, paracristid-protocristid angle 35° or less

• 112. Protoconid height (A, S)

  • 0 = tallest cusp on trigonid

  • 1 = subequal to para- and/or metaconids

  • 2 = smaller than para- and/or metaconid

• 114. Anterior and labial (mesio-buccal) cingular cuspule (f) (A)

  • 0 = present

  • 1 = present with a distinct cingular shelf posteroventrally directed from it

  • 2 = present with shelf continuing along buccal border

  • 3 = absent

• 115. Talonid (A, S)

  • 0 = small heel

  • 1 = multicusped basin

• 117. Trigonid height relative to talonid height (A, S)

  • 0 = twice or more

  • 1 = less than twice

  • 2 = subequal

• 118. Anteroposterior shortening at base of trigonid relative to talonid (A, S)

  • 0 = trigonid long (more than 75 % of tooth length)

  • 1 = some shortening (50-75 % of tooth length)

  • 2 = anteroposterior compression of trigonid (less than 50 % of tooth length)

• 119. Talonid width relative to trigonid (A, S)

  • 0 = very narrow, subequal to base of metaconids

  • 1 = narrower

  • 2 = subequal to wider

• 120. Hypoconulid (A)

  • 0 = absent

  • 1 = in posteromedial position (near the mid-point of transverse talonid width)

  • 2 = lingually placed with slight approximation to entoconid

  • 3 = close approximation to entoconid

• 122. Entoconid (A)

  • 0 = absent

  • 1 = smaller than

  • 2 = subequal to larger than hypoconid and/or hypoconulid

• 123. Postcristid (between entoconid and hypoconulid) taller than hypoconulid and nearly transverse (A)

  • 0 = absent

  • 1 = present

• 124. Mesoconid (A)

  • 0 = absent

  • 1 = present

• 125. Hypolophid (A, S)

  • 0 = absent

  • 1 = present

• 126. Labial postcingulid (A)

  • 0 = absent

  • 1 = present

• 127. Ultimate lower molar size relative to penultimate lower molar (S)

  • 0 = subequal or larger

  • 1 = smaller

  Mandible

• 128. Number of mental foramina (A, S)

  • 0 = two or more

  • 1 = one

• 129. Anteriormost mental foramen (A, S)

  • 0 = below incisors (or anteriormost mandible)

  • 1 = below p1

  • 2 = below p2

  • 3 = more posterior

• 130. Posteriormost mental foramen (A, S)

  • 0 = in canine and anterior premolar (premolariform) region (in saddle behind canine eminence of mandible)

  • 1 = below penultimate premolar (under anterior end of functional postcanine row)

  • 2 = below ultimate premolar

  • 3 = at ultimate premolar and first molar junction or more posterior

• 131. Depth of mandibular body (A, S)

  • 0 = slender and long

  • 1 = deep and short

• 132. Space between ultimate molar and coronoid process (S)

  • 0 = absent

  • 1 = present

• 133. Coronoid process height (S)

  • 0 = higher than condyle

  • 1 = even with condyle

• 134. Coronoid process width (S)

  • 0 = broad, roughly two molar lengths

  • 1 = narrow, subequal to or less than one molar length

• 138. Anteroventral extension of masseteric fossa (S)

  • 0 = absent

  • 1 = extending anteriorly onto mandibular body

• 139. Labial mandibular foramen (S)

  • 0 = absent

  • 1 = present

• 152. Mandibular symphysis posterior extent (S)

  • 0 = p1 or more anterior

  • 1 = p2

  • 2 = p4 or more posterior

• 154. “Meckelian” groove (S)

  • 0 = present

  • 1 = absent

• 156. “Coronoid” facet (S)

  • 0 = present

  • 1 = absent

  Skull – Rostrum

• 164. Exit(s) of infraorbital canal (S)

  • 0 = multiple

  • 1 = single

  • 2 = canal absent

• 165. Infraorbital foramen position (S)

  • 0 = dorsal to ultimate premolar

  • 1 = dorsal to penultimate premolar or more anterior

  • 2 = dorsal to first molar or more posterior

  Skull – Zygoma

• 196. Posterior edge of anterior zygomatic root (S)

  • 0 = aligned with last molar

  • 1 = aligned with anterior molars

  • 2 = aligned with premolars

• 198. Jugal (S)

  • 0 = present

  • 1 = absent

• 199. Jugal (S)

  • 0 = contributes to anteroventral orbit and zygoma

  • 1 = contributes to zygoma

• 200. Maxillary-jugal contact bifurcated (S)

  • 0 = absent

  • 1 = present

• 201. Jugal-lacrimal contact (S)

  • 0 = present

  • 1 = absent

• 202. Zygomatic arch (S)

  • 0 = stout

  • 1 = delicate

  • 2 = incomplete

Matrix

Scored characters for Alvuegena and Schowalteria. All others can be found in Wible et al. (2009).

Alveugena

0010?13??????0????????11010?1?201?-100110100?0010---000000?0?100120020010020001001001??322??2101?210000110000?-00-31?0111?20000?0120????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?

Schowalteria

001?0??2?1???01?00??0011010?1?2010-??00??2???0011--000001?011001200200100-00??????????3??????0??1100?????100???1??1?001?????0?10220100???10????????????2?1-1???????11??????????????????????????????1?00002??????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????

Complete Eutherian tree

Fig. 3

External relations among Eutheria from cladistic analysis. Entirety of tree from Fig. 2, showing both crown and stem relationships