Stenocercus varius Boulenger, 1885

Torres-Carvajal, Omar, 2007, A TAXONOMIC REVISION OF SOUTH AMERICAN STENOCERCUS (SQUAMATA: IGUANIA) LIZARDS, Herpetological Monographs 21 (1), pp. 76-178 : 163-164

Stenocercus varius Boulenger

( Fig. 22 )

Stenocercus varius Boulenger, 1885 a:134 . Holotype: BM 71.4.16.53 , male, ‘‘unknown locality̕̕ (restricted to Tandapi, 1460 m, Provincia Pichincha, Ecuador, by Fritts [1974]); Burt and Burt, 1931:288; Burt and Burt, 1933:44; Peters, 1967:35; Etheridge, in Peters and Donoso-Barros, 1970:257; Fritts, 1974:67; Torres-Carvajal, 2000:31.

Diagnosis.— Stenocercus varius is distinguished from other species of Stenocercus except S. boettgeri , S. haenschi , and S. humeralis by having granular scales on the posterior surface of thighs, enlarged vertebrals, three caudal whorls per autotomic segment, a medially complete antegular fold, non-spinose caudals, and by males lacking a black transverse band on the ventral surface of neck. S. varius differs from these species (character states in parentheses) by having 74–88 (X = 82.35) scales around midbody (79–104, X = 88.61 in S. boettgeri ; 57–64, X = 60.50 in S. haenschi ; 98–125, X = 110.05 in S. humeralis ), 60–85 (X = 69.53) vertebrals (64– 93, X = 76.86 in S. boettgeri ; 50 in S. haenschi ; 81–112, X = 92.21 in S. humeralis ). S. varius is morphologically more similar to S. boettgeri ; however, both males and females of S. boettgeri get larger (maximum SVL = 108 and 94 mm, respectively) than S. varius (maximum SVL = 85 in both sexes).

Description.—(1) Maximum SVL in males 85 mm (n = 16); (2) maximum SVL in females 85 mm (n = 16); (3) vertebrals 60–85; (4) paravertebrals 76–104; (5) scales around midbody 74–88; (6) supraoculars 4–7; (7) internasals 3–5; (8) postrostrals 5–7; (9) loreals 2–4; (10) gulars 39–60; (11) subdigitals on Finger IV 24–28; (12) subdigitals on Toe IV 27–34; (13) posthumeral mite pocket present as one or more vertical folds or ridges; (14) postfemoral mite pocket distinct with slit-like opening; (15) parietal eye not visible through interparietal cornea; (16) scales on occipitoparietal region small, smooth, juxtaposed; (17) projecting angulate temporals absent; (18) row of enlarged supraoculars occupying most of supraocular region absent; (19) scales on frontonasal region juxtaposed anteriorly; (20) preauricular fringe present; (21) antegular (continuous medially), antehumeral, gular, longitudinal, oblique, postauricular, and supra-auricular neck folds present; (22) lateral nuchals less than half the size of dorsal nuchals; (23) posterior gulars cycloid, smooth, slightly imbricate, not notched; (24) lateral scales reduced in size, approximately half the size of dorsal body scales; (25) vertebrals larger than adjacent paravertebrals; (26) dorsolateral crest absent; (27) ventrals smooth, imbricate; (28) scales on posterior surfaces of thighs granular; (29) inguinal granular pocket present; (30) inguinal groove present; (31) preanals not projected; (32) tail not compressed laterally in adult males; (33) tail length 60–66% of total length; (34) caudal whorls per autotomic segment three; (35) caudals not spinose; (36) dark brown stripe extending anterodorsally from subocular region to supraciliaries absent; (37) dark patch extensively covering gular region of females absent; (38) dark patch extensively covering gular region of adult males absent; (39) black patch on ventral surface of neck in adult males absent; (40) dark midventral longitudinal mark such as faint line, conspicuous stripe, or extensive patch in adult males absent; (41) dark patches on ventral surface of thighs in adult males absent; (42) postxiphisternal inscriptional ribs not in contact midventrally, Patterns 1A, 2A, 2B, and 2C.

Color in life.—Dorsum olive-green or light green with scattered yellowish-green spots and dark brown transverse marks longitudinally arranged over vertebral line in some specimens; large, rhomboidal, black mark on shoulder in some males; dorsal surface of head with black and brown marks; gular and pectoral regions yellow; venter yellowish cream; iris bronze ( Torres-Carvajal, 2000).

Natural History.—An adult female collected in October 1995 contained two oviductal eggs; the smallest individual was collected in May 1988 and had a total length of 134 mm (SVL = 45 mm, TL = 89 mm). A temperature of 34.2 C was recorded from a single female specimen ( Torres-Carvajal, 2000). Fritts (1974) observed this species on tree trunks, fallen logs, and rocks.

Distribution.— Stenocercus varius occurs in the western Cordillera of Ecuador (northern Andes) between 1 ° S–1 ° N ( Fig. 8 ). This species is known from the upper valleys of Río Blanco and Río Toachi (Pacific drainage) in Provincias Cotopaxi and Pichincha at elevations of 1460–2200 m.

Figures

FIG. 22.—Six species of Stenocercus. (A) S. stigmosus (PVE); (B) S. torquatus (MLU); (C) S. trachŋcephalus (JMR); (D) S. tricristatus (illustration from plate XXII in Duméril, 1856); (E) S. Ʋariabilis (MLU); (F) S. Ʋarius (LAC).

FIG. 8.—Distribution of six species of Stenocercus in Colombia and Ecuador.