Stenocercus haenschi (Werner)

Torres-Carvajal, Omar, 2007, A TAXONOMIC REVISION OF SOUTH AMERICAN STENOCERCUS (SQUAMATA: IGUANIA) LIZARDS, Herpetological Monographs 21 (1), pp. 76-178 : 123-124

Stenocercus haenschi (Werner)

Liocephalus formosus Boulenger, 1880:43 . Holotype: MRHN 2007 from ‘‘Andes of Ecuador̕̕ (restricted to Balsapamba, 750 m, Provincia Bolívar, Ecuador, by Fritts [1974]); Boulenger, 1885 a:168. Replacement of the name Liocephalus formosus with the junior synonym Liocephalus haenschi was necessary because L. formosus became a junior secondary homonym of Scelotrema formosum when both taxa were combined into Stenocercus . Synonymy fide Fritts, 1974:55.

Liocephalus haenschi Werner, 1901 a:595 . Holotype: ZMB 16595 , a male from ‘‘ Balsapamba [Provincia Bolívar], 750 m, Ecuador ̕̕.

Leiocephalus haenchi Burt and Burt, 1933:27 .

Ophryoessoides formosus Peters, 1967:28 ; Etheridge, in Peters and Donoso-Barros, 1970:214.

Ophryoessoides haenschi Etheridge, 1966:88 ; Peters, 1967:28; Etheridge, in Peters and Donoso-Barros, 1970:214.

Stenocercus haenschi Fritts, 1974:55 ; Torres-Carvajal, 2000:21.

Diagnosis.— Stenocercus haenschi is distinguished from other species of Stenocercus except S. boettgeri , S. humeralis , and S. varius 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. haenschi differs from these species by having fewer scales (57–64, X = 60.50) around midbody (79–104, X = 88.61 in S. boettgeri ; 98–125, X = 110.05 in S. humeralis ; 74–88, X = 82.35 in S. varius ). Additionally, the temporals and lateral body scales in S. haenschi are keeled and imbricate (smooth or granular in the other three species).

Description.—(1) Maximum SVL in males 76 mm (n = 1); (3) vertebrals 50; (4) paravertebrals 64; (5) scales around midbody 57–64 (lower count taken from Fritts, 1974); (6) supraoculars five; (7) internasals three; (8) postrostrals four; (9) loreals three; (10) gulars 56; (11) subdigitals on Finger IV 26–28; (12) subdigitals on Toe IV 30; (13) posthumeral mite pocket present as one or more vertical folds or ridges; (14) postfemoral mite pocket present as one or more vertical folds or ridges; (15) parietal eye not visible through interparietal cornea; (16) scales on occipitoparietal region small, smooth or multicarinate, juxtaposed; (17) two projecting angulate temporals absent; (18) row of enlarged supraoculars occupying most of supraocular region absent; (19) scales on frontonasal region juxtaposed; (20) preauricular fringe present; (21) antegular (continuous medially), antehumeral, gular, longitudinal, and postauricular neck folds present; (22) lateral nuchals less than half the size of dorsal nuchals; (23) posterior gulars rhomboidal, smooth or slightly keeled, 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 61% 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; (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, Pattern 2B.

Color in preservative of holotype.—Flanks grayish green with pale green spots; large black blotch on shoulder; irregular dark transverse stripes on limbs; dorsum of head olive-brown; gular region grayish green with pale spots; venter bluish green; dorsal aspect of tail brown with dark transverse bands; ventral surface of tail gray with narrow, pale transverse bands ( Werner, 1901 a).

Natural History.— Fritts (1974) suggested that this species is arboreal because of the large number of subdigitals on Finger IV.

Distribution.— Stenocercus haenschi occurs in the northern Andes and is known only from its type locality (Balsapamba, 1 ° 46'0"S, 79 ° 11'0"W, 750 m, Provincia Bolívar) on the western slopes of the western Cordillera in Ecuador ( Fig. 9 ). This locality lies in the upper valley of Río Babahoyo (Pacific drainage); habitat destruction has probably reduced or eliminated populations of S. haenschi in this area ( Torres-Carvajal, 2000).

Figures

FIG. 9.—Distribution of six species of Stenocercus in Ecuador.