Stenocercus Dumeril and Bibron
Creators: name: Torres-Carvajal, Omar
Publisher: name: Zenodo
Year: 2007
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Squamata
Tropiduridae
Stenocercus

description: Stenocercus Duméril and Bibron
Stenocercus Duméril and Bibron, 1837 (4): 349.
Type species (by monotypy): Stenocercus roseiventris Duméril and Bibron, 1837.
Trachycyclus Duméril and Bibron, 1837 (4): 355. Type species (by monotypy): Trachycyclus marmoratus Duméril and Bibron, 1837.
Proctotretus Duméril and Bibron, 1837 (4): 266. Type species (subsequent designation by Fitzinger, 1843): Proctotretus pectinatus Duméril and Bibron, 1837.
Heterotropis (Trachycyclus) Fitzinger, 1843: 71. Type species (by monotypy): Trachycyclus marmoratus Duméril and Bibron, 1837.
Steironotus (Stenocercus) Fitzinger, 1843:71. Type species (by monotypy): Stenocercus roseiventris Duméril and Bibron, 1837.
Scelotrema Tschudi, 1845:154. Type species: none designated.
Ptygoderus Gray, 1845:216. Type species (by monotypy): Proctotretus pectinatus Duméril and Bibron, 1837.
Ophryoessoides Duméril, in Duméril and Duméril, 1851:66. Type species (by monotypy): Ophryoessoides tricristatus Duméril, in Duméril and Duméril, 1851.
Brachysaurus Hallowell, 1856:232. Type species (by monotypy): Brachysaurus erythrogaster Hallowell, 1856.
Saccodeira Girard, 1857:197. Type species (by monotypy): Saccodeira ornatissima Girard, 1857.
Microphractus Günther, 1859 a:90. Type species (by monotypy): Microphractus humeralis Günther, 1859.
Scartiscus Cope, 1862:182. Type species (by monotypy): Scartiscus caducus Cope, 1862.
Tropidocephalus Müller, 1880:45. Type species (by monotypy): Tropidocephalus azureus Müller, 1880.
Diagnosis.— Stenocercus can be distinguished from other iguanian genera by the following combination of characters (Arnold, 1984; Boulenger, 1885 a; Frost and Etheridge, 1989; Frost, 1992; Frost et al., 2001 b): (1) maxillae do not articulate anteromedially posterior to palatal portion of premaxilla; (2) premaxillary spine not overlapped by nasals; (3) nasal concha fused to roof of nasal chamber; (4) jugal and squamosal not broadly juxtaposed; (5) parietal roof trapezoidal in shape; (6) parietal foramen in frontoparietal suture or absent; (7) supratemporal overlaps lateral aspect of supratemporal process of parietal; (8) nuchal endolymphatic sacs do not penetrate nuchal musculature; (9) labial blade of coronoid poorly developed or absent; (10) anterior surangular foramen dorsal to posteriormost extent of dentary; (11) marginal teeth pleurodont; (12) palatine teeth absent; (13) posterior coracoid fenestra present; (14) anterior process of interclavicle poorly developed or absent; (15) posterior process of interclavicle anterior to contact with sternum long; (16) sternal ribs three; (17) interparietal scale not enlarged; (18) gular scales imbricate posteriorly; (19) gular fold incomplete medially; (20) femoral pores absent; (21) preanal pores absent; (22) hemipenes weakly bilobate, with distinctly divided sulci; (23) hemipenial sheath musculature extensive; (24) hemipenial dorsal accessory muscle absent; (25) colic septa absent.
KEY TO THE SPECIES OF STENOCERCUS
1. Scales on posterior surface of thighs granular _ _ _ _ 2
Scales on posterior surface of thighs flat, smooth or keeled, imbricate _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 28
2. Vertebral scales similar in size to adjacent paravertebral scales _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 3
Some or all vertebral scales larger than adjacent paravertebral scales, forming distinct middorsal row _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 13
3. Caudal whorls per autotomic segment two; caudal scales moderately to strongly mucronate _ _ 4
Caudal whorls per autotomic segment three; caudal scales not mucronate _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 6
4. Caudal scales strongly spinose _ _ _ _ _ _ _ _ _ S. eunetopsis
Caudal scales mucronate but not strongly spinose _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 5
5. Scales around midbody 51–66; tail length 59–67% of total length _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. cupreus
Scales around midbody 85–111; tail length 0.53–0.61 of total length _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. empetrus
6. Mite pocket underneath oblique neck fold deep _ _ 7
If present, mite pocket underneath oblique neck fold shallow _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 8
7. Lateral and dorsal nuchals similar in size; venter of adult males generally uniform in color _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. latebrosus
Lateral nuchals less than half the size of dorsal nuchals; venter of adult males with scattered black dots _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. ornatissimus
8. Lateral nuchals similar in size to dorsal nuchals _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. ivitus
Lateral nuchals less than half the size of dorsal nuchals _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 9
9. Dorsal head scales prominently keeled _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. orientalis
Dorsal head scales smooth _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 10
10. Scales around midbody fewer than 40; tail length at least 70% of total length _ _ _ _ _ S. modestus
Scales around midbody more than 40; tail length less than 70% of total length _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 11
11. Oblique neck fold absent; posthumeral mite pocket absent _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. melanopygus
Oblique neck fold present; posthumeral mite pocket present as one or more vertical folds or ridges _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 12
12. Antehumeral fold weakly developed; mite pockets underneath oblique and antehumeral neck folds absent; males with distinct black spots on venter _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. stigmosus
Antehumeral fold strongly developed; distinct mite pockets underneath oblique and antehumeral neck folds; ventral color pattern in males variable, but never with distinct black spots _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. chrysopygus
13. Caudal whorls per autotomic segment two _ _ _ _ _ _ 14
Caudal whorls per autotomic segment three _ _ _ _ 20
14. Dorsal scales on neck and body keeled and imbricate _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 15
Dorsal scales on neck and body granular _ _ _ _ _ _ _ _ _ 17
15. Adult males with black vertical bar anterior to each fore limb, sometimes forming antehumeral collar _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 16
Adult males lack antehumeral collar, scales around midbody 66–96 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. carrioni
16. Scales on flanks granular; scales around midbody 80–110 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. chlorostictus
Scales on flanks keeled and imbricate; scales around midbody 67–82 _ _ _ _ _ _ _ _ S. bolivarensis
17. Lateral nuchal scales less than half the size of dorsal nuchal scales _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. empetrus
Lateral and dorsal nuchal scales similar in size _ _ 18
18. Scales around midbody 79–102 _ _ _ _ _ _ _ _ _ _ S. simonsii
Scales around midbody generally more than 100 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 19
19. Adult males with complete black antehumeral collar followed anteriorly by two black transverse bars on the neck; caudal scales strongly spinose; tail length 47–54% of total length _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. torquatus
Color pattern in adult males not as described above; caudal scales moderately spinose; tail length 57–62% of total length _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. crassicaudatus
20. Antegular folds usually meet ventromedially forming continuous transverse fold_ _ _ _ _ _ _ _ _ 21
If present, antegular folds never meet ventromedially _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 26
21. Adult males with black transverse band on ventral surface of neck and lavender ventral background _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 22
Color pattern in adult males not as described above _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 23
22. Vertebrals fewer than 65 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. imitator
Vertebrals more than 65_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. praeornatus
23. Scales around midbody fewer than 65; scales on temporal region and flanks distinctly keeled and imbricate _ _ _ _ _ _ _ _ _ _ S. haenschi
Scales around midbody more than 65; scales on temporal region and flanks granular, or smooth or slightly keeled and imbricate _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 24
24. Lateral and dorsal nuchal scales granular and similar in size _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. humeralis
Lateral nuchal scales granular, less than half the size of keeled and subimbricate dorsal nuchal scales_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 25
25. Scales around midbody 74–88; black patch on shoulder in some males _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. varius
Scales around midbody 79–104; black patch on shoulder in males absent _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. boettgeri
26. Lateral and dorsal body scales similar in size; generally more than 90 scales around midbody _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. nubicola
Lateral body scales reduced in size, approximately half the size of dorsal scales; generally fewer than 90 scales around midbody _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 27
27. Postfemoral mite pocket deep _ _ _ _ _ _ _ _ _ _ _ S. variabilis
Postfemoral mite pocket absent _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. frittsi
28. Caudal fracture planes present _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 29
Caudal fracture planes absent _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 57
29. Caudal whorls per autotomic segment two _ _ _ _ _ _ 30
Caudal whorls per autotomic segment three or four _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 34
30. Caudal scales strongly spinose; preanals not projected _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 31
Caudal scales not spinose; preanals posteriorly projected, forming denticulate border _ _ _ _ _ 32
31. Vertebral crest conspicuous and continuous; lateral body scales approximately half the size of dorsal scales _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. roseiventris
Vertebral crest low and discontinuous; lateral and dorsal body scales similar in size _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. marmoratus
32. Ventral scales strongly keeled _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. azureus
Ventral scales smooth_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 33
33. Antehumeral fold present; four phalanges in Finger IV _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. pectinatus
Antehumeral fold absent; five phalanges in Finger IV _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. doellojuradoi
34. Caudal whorls per autotomic segment three _ _ _ _ 35
Caudal whorls per autotomic segment four _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. formosus
35. Nostrils lateral to canthal ridge _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 36
Nostrils medial to canthal ridge_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 40
36. Postfemoral mite pocket present _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 37
Postfemoral mite pocket absent_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 38
37. Postfemoral pocket deep; tail in adult males slightly compressed _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. aculeatus
Postfemoral pocket shallow; tail in adult males strongly compressed laterally _ _ _ S. angulifer
38. Posthumeral mite pocket covered by axillary flap; scales on dorsal aspect of thigh not projected _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 39
Posthumeral mite pocket not covered by axillary flap; dorsal aspect of thigh with one row of enlarged, projecting scales _ _ _ _ S. fimbriatus
39. Two projecting angulate temporals; vertebral crest strongly projected _ _ _ _ _ _ _ _ _ _ _ _ _ S. prionotus
Angulate temporals not projected; vertebral crest less projected_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. caducus
40. Longitudinal row of enlarged supraoculars occupying most of the supraocular region _ _ _ _ _ _ _ _ 41
Longitudinal row of enlarged supraoculars occupying most of the supraocular region absent _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 46
41. Postfemoral mite pocket present _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 42
Postfemoral mite pocket absent _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 45
42. Two or three dorsally-projected angulate temporals; one canthal _ _ _ _ _ _ _ _ _ _ _ _ _ S. huancabambae
Angulate temporals not projected; two canthals 43
43. Dorsal head scales smooth; ventral scales smooth and imbricate _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. puyango
Dorsal head scales keeled; ventral scales keeled and imbricate _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 44
44. Adult males with black blotch on ventral surface of neck; vertebral crest in males conspicuous but not strongly projected _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. limitaris
Adult males lack black blotch on ventral surface of neck; vertebral crest in males strongly projected _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. santander
45. Dorsal head scales keeled or wrinkled; ventral scales distinctly keeled in juveniles and adults _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. erythrogaster
Dorsal head scales smooth; ventral scales slightly keeled in juveniles, smooth in adults _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. iridescens
46. Postfemoral mite pocket absent _ _ _ _ _ S. apurimacus
Postfemoral mite pocket distinct, with vertical or posteroventrally oriented slitlike opening _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 47
47. Antehumeral fold present_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 48
Antehumeral fold absent _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 51
48. Oblique neck fold present_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. ochoai
Oblique neck fold absent _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 49
49. Posthumeral mite pocket shallow; males with black patches on ventral surface of thighs; maximum SVL approximately 80 mm in males and 65 mm in females _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. nigromaculatus
Posthumeral mite pocket deep; males without black patches on ventral surface of thighs; maximum SVL more than 80 mm in males and more than 65 mm in females _ _ _ _ _ _ 50
50. Posterodorsal head scales juxtaposed, protuberant, and wrinkled or multicarinate; black gular patch in adult males; parietal eye not visible through interparietal cornea _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. percultus
Posterodorsal head scales subimbricate with a central keel; gular region in adult males not black; parietal eye usually visible through interparietal cornea _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. ornatus
51. Posthumeral mite pocket deep with narrow opening; ventral aspect of hind limbs in adult males covered by black patch _ _ _ _ _ _ _ _ _ _ S. rhodomelas
Posthumeral mite pocket absent or shallow with wide opening; ventral aspect of hind limbs in adult males not covered by black patch _ _ 52
52. Posthumeral mite pocket absent _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 53
Posthumeral mite pocket shallow with wide opening _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 54
53. Ventral scales weakly keeled; tail in adult males strongly compressed; scales around midbody generally fewer than 60 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. trachycephalus
Ventral scales smooth; tail in adult males weakly compressed; scales around midbody more than 60 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. lache
54. Scales around midbody generally more than 60 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. guentheri
Scales around midbody generally fewer than 60 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 55
55. Black transverse band on ventral surface of neck in adult males generally present; venter extensively covered with black in some males _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. festae
Black transverse band on ventral surface of neck in adult males absent; longitudinal black midventral stripe usually present in adult males; venter not extensively covered with black _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 56
56. Black midventral stripe in most adult males; black blotches on gular region of juveniles and females _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. chota
Black midventral stripe in adult males absent; black blotches on gular region of juveniles and females absent _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. angel
57. Posthumeral and postfemoral mite pockets present _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. scapularis
Posthumeral and postfemoral mite pockets absent _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 58
58. Posterior supraciliaries enlarged, projected; head pyramidal in shape _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 59
Posterior supraciliaries not enlarged, not projected; head not pyramidal in shape _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. sinesaccus
59. Tail length 53–63% of total length _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 60
Tail length 44–52% of total length _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 61
60. Posterior supraciliaries distinctly pointed; two enlarged scales above tympanum; tibia about as long as thigh; scales around midbody more than 40 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. dumerilii
Posterior supraciliaries blunt; scales above tympanum not enlarged; tibia shorter than thigh; scales around midbody fewer than 40 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. tricristatus
61. Tail length at least 50% of total length; vertebral, paravertebral and lateral crests inconspicuous _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. quinarius
Tail length less than 50% of total length; vertebral, paravertebral, and lateral crests prominent _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ S. squarrosus
description: Published as part of Torres-Carvajal, Omar, 2007, A TAXONOMIC REVISION OF SOUTH AMERICAN STENOCERCUS (SQUAMATA: IGUANIA) LIZARDS, pp. 76-178 in Herpetological Monographs 21 (1) on pages 79-166, DOI: 10.1655/06-001.1, http://zenodo.org/record/14384794