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SUPPLEMENTARY INFORMATION
Large Cretaceous sphenodontian from Patagonia sheds light on lepidosaur
evolution in Gondwana
Sebastián Apesteguía * & Fernando E. Novas †
*Dirección de Cultura de la Provincia de Río Negro, Sarmiento 252, Viedma
(8300), Río Negro, Argentina
†Museo Argentino de Ciencias Naturales "Bernardino Rivadavia", Av. Ángel
Gallardo 470, Buenos Aires (1405), Argentina
Cladistic Analysis. List of 69 characters and data matriz used to analyze the
phylogenetic relationships of Priosphenodon avelasi in figure 2. The list of
characters is modified from the following sources: Rasmussen & Callison (1981);
Benton (1985); Gauthier et al. (1988); Evans (1988); Fraser & Benton (1989); Wu,
(1994); Sues et al. (1994); and Reynoso (1996; 1997; 1998; 2000).
Character list
1. Antorbital length / skull length ratio (Reynoso, 1996, ch.1; Wu, 1994, ch.11, 12;
Sues et al., 1994, ch.11): More or equal than 1/3 (0); between 1/3 and ¼ (1); less
or equal than ¼ (2).
2. Orbit diameter / skull length ratio (Reynoso & Clark, 1998, ch.49): 1/3 or more
(0); less than 1/3 (1).
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3. Supratemporal fenestra / orbit length ratio (Sues et al., 1994, ch.12): Less than
75% (0); more than 75% (1).
4. Supratemporal fenestra / skull length ratio (Reynoso, 1996, ch.2; Wu, 1994,
ch.13): Less than ¼ (0); more than ¼ (1).
5. Lower temporal fenestra / skull length ratio (Reynoso, 1996, ch.3; Wu, 1994,
ch.14): Less or equal than ¼ (0); more than ¼ (1).
6. Maxilla with premaxillary process (Reynoso, 1996, ch.4; Wu, 1994, ch.1; Sues et
al., 1994, ch.2): elongate (0); short or absent (1).
7. Premaxillary posterodorsal process (which excludes the maxilla from the
external naris margin) (Sues et al., 1994, ch.1; Reynoso, 1997, ch.43): absent (0);
present (1).
8. Posterior end of the maxilla (Reynoso, 1996, ch.5; Wu, 1994, ch.2): narrow or
tapers (0); broad dorso-ventrally (1).
9. Lacrimal (Reynoso, 1996, ch.6; Wu, 1994, ch.3; Sues et al., 1994, ch.3):
present (0); absent (1).
10. Jugal dorsal process (Reynoso, 1996, ch.7; Wu, 1994, ch.9): broad and short
(0); narrow and elongate (1).
11. Prefrontal and postfrontal profusely sculptured: absent (0); present (1).
12. Prefrontal - jugal contact (Sues et al., 1994, ch.4; Reynoso, 1997, ch.44):
absent (0); present (1).
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13. Postorbital with marked dorsal ridge and deep ventrolateral concavity: absent
(0); present (1).
14. Frontals (Reynoso, 1996, ch.8; Wu, 1994, ch.4; Sues et al., 1994, ch.5):
separate (0); fused (1).
15. Parietals (Reynoso, 1996, ch.9; Wu, 1994, ch.5; Sues et al., 1994, ch.6):
separate (0); fused (1).
16. Interparietal / interorbital width or intertemporal width of parietals (Reynoso,
1996, ch.10; Wu, 1994, ch.6; Sues et al., 1994, ch.7): broader or greater than
interorbital width (0); narrower or less than interorbital width (1).
17. Parietal crest (Reynoso, 1996, ch.11; Wu, 1994, ch.7; Sues et al., 1994, ch.8):
absent (0); present (1).
18. Posterior edge of parietals (Reynoso, 1996, ch.12; Wu, 1994, ch.8): greatly
incurved (0); slightly incurved (1); convex (2).
19. Parietal foramen, position respect to the anterior border of the supratemporal
fenestra (Reynoso, 1996, ch.13; Wu, 1994, ch.10; Sues et al., 1994, ch.10):
posterior (0); at the same level or anterior (1).
20. Lower temporal bar shape / position (Reynoso, 1996, ch.14; Wu, 1994, ch.17;
Sues et al., 1994, ch.15): aligned with maxilary tooth row (0); bowed (1).
21. Lower temporal bar (Reynoso, 1996, ch.15; Wu, 1994, ch. 18; Sues et al.,
1994, ch.16): incomplete (0); complete (1).
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22. Palatines posterior shape (Reynoso, 1996, ch.16; Wu, 1994, ch.33; Sues et al.,
1994, ch.29): tapers posteriorly (0); relatively wide posteriorly (1).
23. Pterygoid bones anterior contact (Reynoso, 1997, ch.48): absent (0); slight (1);
vast (2).
24. Interpterygoid vacuity posterior opening or relative separation of the pterygoid
posteromedial processes (Reynoso, 1997, ch. 47): widely open (0); as wide as
vacuity (1); almost close (2).
25. Pterygoid central region, between the three ramii (Reynoso, 1996, ch.17; Wu,
1994, ch.34; Sues et al., 1994, ch.30): short (0); elongate (1).
26. Pterygoid (Reynoso, 1996, ch.18; Wu, 1994, ch.35; Sues et al., 1994, ch.32):
entering into margin of suborbital fenestra (0); excluded from margin of suborbital
fenestra(1).
27. Suborbital fenestra (Sues et al., 1994, ch.33; Reynoso, 1997, ch.46): maxilla
entering into suborbital fenestra (0); maxilla excluded (1).
28. Q-Qj foramen size (Reynoso & Clark, 1998, ch. 51): small (0); enlarged (1).
29. Q-Qj foramen position (Reynoso & Clark, 1998, ch. 52): between Q and Qj (0);
in Q (1).
30. Q-Qj conch size and emargination (Reynoso & Clark, 1998, ch. 50; Evans,
1988, ch.K23; Sues et al., 1994, ch.18): pronounced (0); reduced (1).
31. Supratemporal (Sues et al., 1994, ch.9; Reynoso, 1997, ch.45): present (0);
fused or absent (1).
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32. Inferred jaw motion (Reynoso, 1996, ch.19; Wu, 1994, ch.36; Sues et al., 1994,
ch.34): orthal (0); propalineal (1).
33. Degree of propalinality, measured either as palatal tooth row extension or
length in which palatines keep parallel to the maxillae (Reynoso, 1996, ch.35; Wu,
1994, ch.30; Sues et al., 1994, ch.26): small palatal row, parallel line restricted to
the anterior region (0); enlarged, palatines accompanying maxilla half its own
length (1); palatines accompanying maxilla by its complete length, ‘eupropalinality’
(2).
34. Lower jaw, anterior region: toothed (0); edentate (1). This character was not
applied to Zapatadon nor Pamizinsaurus because of its immature ontogenetic
stage.
35. Mandibular symphisis breath (Reynoso, 1996, ch.21; Benton, 1985, ch.Z13,
states 2 and 3 added): slender (0); broad (1); broad with a sharp posteroventral
process (2); broad with a rounded but well defined ventromedial process (3).
36. Jaw symphisis: symphisis vertical, devoid of ventral projections (0); symphisis
anterodorsally projected, with rostral margin forming an angle > 120 degrees with
the ventral margin of dentary (1); symphisis vertical but with several ventral
projections (2).
37. Jaw symphisis, dorsal development: moderately developed (0); well projected
anterodorsally, comparable to a caniniform (1).
38. Mandibular foramen (Reynoso, 1996, ch.22; Benton, 1985, ch.Z15): small (0);
large (1).
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39. Glenoid cavity: smooth surface, lacking an anteroposterior central ridge (0);
elongate and asymmetrical surface, with a strong anteroposterior central ridge (1);
symmetrical facet with a strong anteroposterior central ridge (2).
40. Coronoid process (Reynoso, 1996, ch.24; Wu, 1994, ch.16; Sues et al, 1994,
ch.14; last state added): short, weak or absent, less than half jaw (0); pronounced,
around half jaw (1); high, as tall as jaw (2).
41. Retroarticular process (Reynoso, 1996, ch.25; Wu, 1994, ch.19; and Sues et
al.,1994, ch.17, last state added): pronounced (0); reduced, caudally projected (1),
reduced, dorsally curved (2).
42. Posterior process of dentary (modified from Sues et al., 1994, ch.13): short,
does not reaching glenoid level (0); elongate, reaching glenoid level (1); elongate,
reaching the end of glenoid level (2).
43. Marginal dental implantation (Reynoso, 1996, ch.26; Wu, 1994, ch.21,
modified; Sues et al., 1994, ch.19, modified): pleurodont (0); degree of posterior
acrodonty (1); fully acrodont (2).
44. Tooth replacement (Reynoso, 1996, ch.27; Benton, 1985, ch.Z8): alternate (0);
addition at back of jaw (1).
45. Dentary regionalization with small juvenile teeth (hatchling) in the anterior
region of maxilla and dentary (Reynoso, 1996, ch.30; Benton, 1985, ch.Z7; last two
states added): absent, only pleurodont teeth (0); present, with hatchling pleurodont
teeth (1); present, with hatchling, successional and additional acrodont teeth (2);
absent, only additional acrodont teeth (3).
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46. Anterior caniniform teeth in maxillae and dentaries (Reynoso, 1996, ch.31;
Gauthier et al., 1988, ch.51): absent (0); present (1).
47. Lateral and medial wear facets on marginal teeth (Reynoso, 1996, ch.28; Wu,
1994, ch.27; Sues et al., 1994, ch.23): absent or smooth (0); well established (1).
48. Marginal teeth breath (Reynoso, 1996, ch.29; Fraser & Benton, 1989, ch.27;
one state added): circular shape, equal or lesser to length (0); square-shape,
expanded lateromedially (1); rectangular shape, wider than long (2).
49. Number of premaxillary teeth (Reynoso, 1996, ch.32; Wu, 1994, ch.22,23 and
24 combined; Sues et al., 1994, ch.20): more than seven (0); seven to four (1);
three or less (2).
50. Premaxillary teeth structure (Reynoso, 1996, ch.33; Wu, 1994, ch.25; Sues et
al., 1994, ch.21): discrete (0); chissel-like (1).
51. Maxillary teeth shape (Reynoso, 1996, ch.34; Wu, 1994, ch.26 and 29; Sues et
al., 1994, ch.22, with an added state): simple cones (0); small occasional
posteromedial flanges (1); extensive posteromedial flanges (2).
52. Maxillary teeth with anterolateral flange: absent (0); present (1).
53. Number of palatine tooth rows (Reynoso, 1996, ch.36; Wu, 1994, ch.31; Sues
et al., 1994, ch.27): more than one (0); a single row plus one isolated relictual
tooth (1); a single lateral tooth row (2).
54. Palatine teeth with flanges (Reynoso, 1996, ch.37; Fraser & Benton, 1989,
ch.15): absent (0); present on some (1).
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55. Stabbing palatine (anterior region of the palatine with hypertrophied tooth):
absent (0); present (1).
56. Number of pterygoid tooth rows (Reynoso, 1996, ch.38; Wu, 1994, ch.32; and
Sues et al., 1994, ch.28, modified): three or more rows (0); two rows (1); one row
or absent (2).
57. Mandibular teeth with anterolateral flanges (Reynoso, 1996, ch.39; Wu, 1994,
ch.28; Sues et al., 1994, ch.24): absent (0); present, at least in one tooth (1).
58. Mandibular teeth with anteromedial flanges: absent (0); present (1).
59. Dental ridges in adult additional teeth: absent (0); present (1).
60. 2nd sacral vertebra with posterior process (Reynoso, 1996, ch.40; Gauthier et
al., 1988, ch.88, modified): small (0); prominent (1); absent (2).
61. Ischium posterior border (Reynoso, 1996, ch.41; Evans, 1988, ch.K14; Fraser
& Benton, 1989, ch.4): posterior end uninterrupted (0); tubercle on posterior end
(1); prominent posterior process (2).
62. Humerus respect to the presacral vertebrae length (Reynoso, 1996, ch.42;
Fraser & Benton, 1989, ch.29): 0.2 or less (0); more than 0.2 (1).
63. Tibia respect to the presacral vertebrae length (Reynoso, 1996, ch.42; Fraser &
Benton, 1989, ch.29): 0.25 or less (0); more than 0.25 (1).
64. Femur respect to the presacral vertebrae length (Reynoso, 1996, ch.42; Fraser
& Benton, 1989, ch.29): less than 0.3 (0); equal or larger to 0.3 (1).
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65. Radius length / presacral vertebrae length (Reynoso, 1996, ch.42; Fraser &
Benton, 1989, ch.29): less than 0.15 (0); equal or larger to 0.15 (1).
66. Skull length: lesser than 30 mm (0); 30-90 mm (1); equal or larger than 100 mm
(2).
67. Postzygapophyses, dorsal shape (Reynoso, 2000, ch.53): flat (0); swollen (1).
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Analysis
The data matrix was analyzed cladistically using the NONA (ver. 1.8)
software package (Goloboff, 1993) and formatting and character exploration was
performed in WinClada (Nixon, 1999). Squamata and Diphydontosaurus were
employed as outgroups. A single tree was obtained, with the following values:
L=140; CI=0.63; RI=0.71.
Unambiguous character support for Sphenodontinae and Opisthodontia is
presented below. The first number refers to the character on the list above, and the
derived state is given in brackets.
Sphenodontinae: 30(1), 55(1), 59(0), 60(2)
Opisthodontia: 11(1), 35(3), 39(2), 45(3), 48(1), 52(1), 58(1)
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Data matrix
SQUAMATA
Diphydontosaurus
Brachyrhinodon
Homoeosaurus
Kallimodon
Sapheosaurus
Palaeopleurosaurus
Clevosaurus hudsoni
Pamizinsaurus
Zapatadon
Sphenodon
Cynosphenodon
Opisthias
Toxolophosaurus
Eilenodon
Priosphenodon
0[01][01]0[01]0?00[01]0?00000000000000---0?0-0000000000000000000--0200?010000-0
100000001000010000010010000000101000010101[01]11000100000000??11000000
211111011100?000000110120??????0??1101?10121201021101??1?????0000??
0[01]0000011000?0000[01]111120010???10??1101?11121201021200??21??12111100
01110?011?00?00111111120010???101?1001?20121201021202??210112000001
11?100?1?0???0011111011001???????11001?20?-?-0--21-0????---120???11
011100001000101112000021100110100111-1?101212010212?20021??11000010
2111111111010001000110210110000011200111012120102120110110111000000
??????1???0????????????211???0001-2101?11?2120?02???2???1?1??????00
10-01??01??1??1?1?1?102210?10101?-111??1??2120?0??1?2??2?????????0?
1111100111001001111111221101011121120111112121102110211210021000010
?????????????????????????1?????1??111??1??2121102100????10???????0?
?1???11111?110011?11?1220??????1213111?0112?30112?2?21021111?????1?
???????????????????????????????1?13111?0??2?3012????????11???????1?
??????????1????????????????????1?13??120222?30122?21210?111??????2?
0110011111111001111101220100000121311120222?3012212121021111?????21
References used for Supplementary Information
Aside from references cited in the text, the following bibliography was consulted:
Benton, M.J. Classification and phylogeny of the diapsid reptiles. Zool. Jour.
of the Linn. Soc. 84, 97-164 (1985).
Evans, S. E. The early history and relationships of the Diapsida In The
Phylogeny and Classification of the Tetrapods (Benton, M. J.; ed.). Vol. 1, 221-260
(1988).
Gauthier, J. A., Estes, R., and De Queiroz, K. A phylogenetic analysis of the
Lepidosauromorpha In Phylogenetic Relationships of the Lizard families: Essays
commemorating Charles M. Camp (Estes, R. & Pregill, G., eds.) Stanford
University Press, 15-98 (1988).
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Goloboff, P. A.. NONA (ver 1.8) , computer program and software.
Published by the author, S.M. de Tucumán, Argentina (1993).
Nixon, K. C.. Winclada (BETA) ver. 0.9.9. published by the author, Ithaca,
New York, USA (1999). Both packages available from http: //www.cladistics.org.
Reynoso, V.H. A Middle Jurassic Sphenodon-like sphenodontian
(Diapsida:Lepidosauria) from Huizachal Canyon, Tamaulipas, México. J. Vert.
Paleontol. 16(2), 210-221 (1996).
Reynoso, V.H. & Clark, J.M. A dwarf sphenodontian from the Jurassic La
Boca Formation of Tamaulipas, México. Jour. of Vert. Paleontol. 18(2), 333-339
(1998).
Sues, H. -D.; Shubin, N. H. & Parks, P. A new sphenodontian (Lepidosauria:
Rhynchocephalia) from the McCoy Brook Formation (Lower Jurassic) of Nova
Scotia, Canada. Jour. of Vert. Paleontol. 14, 327-340 (1994).
Wu, X. Late Triassic-Early Jurassic sphenodontians (Clevosaurus) from
China and the Phylogeny of the Sphenodontida In In the Shadow of the Dinosaurs:
Early Mesozoic Tetrapods (Fraser, N.C. and Sues, H.D., eds.). Cambridge
University Press, 38-69 (1994).