Stenocercus modestus Tschudi

Torres-Carvajal, Omar, 2007, A TAXONOMIC REVISION OF SOUTH AMERICAN STENOCERCUS (SQUAMATA: IGUANIA) LIZARDS, Herpetological Monographs 21 (1), pp. 76-178 : 136-137

Stenocercus modestus Tschudi

( Fig. 20 )

Liolaemus (Sauridis) modestus Tschudi, 1845:157 . Holotype: BM 75.2.13.3 , a male from ‘‘Peru̕̕ (restricted to Miraflores [Departamento Lima], Peru by Tschudi [1846]); Roux, 1907:297.

Stenocercus moestus Boulenger, 1885 a:136 . Holotype: BM 75.2.13.3, a male from ‘‘Lima [Departamento Lima], Peru̕̕; Burt and Burt, 1933:43; Burt and Myers, 1942:307; Etheridge, in Peters and Donoso-Barros, 1970:257; Fritts, 1974:58. Synonymy fide Laurent, 1984:368.

Diagnosis.— Stenocercus modestus is distinguished from other species of Stenocercus except S. chrysopygus , S. cupreus , S. latebrosus , S. orientalis , and S. ornatissimus by having granular scales on the posterior surface of thighs, conspicuous antehumeral and oblique neck folds, a distinct mite pocket under oblique neck fold, and by lacking a vertebral crest. Of these species, S. latebrosus and S. ornatissimus are unique in having deep neck mite pockets under the antehumeral and oblique neck folds, whereas S. orientalis is unique in having prominently keeled dorsal head scales. S. modestus can be distinguished from S. chrysopygus (character states in parentheses) by having keeled and imbricate lateral nuchal scales (granular, or smooth and subimbricate) and a caudal notch on ventral scales (caudal notch on ventrals absent). It can be distinguished from S. cupreus by having three instead of two caudal whorls per autotomic segment. S. modestus has fewer vertebrals (39–46, X = 42.00) and fewer scales around midbody (32–38, X = 35.17) than S. chrysopygus (54–86, X = 66.01 and 48–82, X = 64.31, respectively) and S. cupreus (44–58, X = 51.53 and 51–66, X = 59.47, respectively). In addition, S. modestus differs from the above mentioned species in having a much longer tail (tail length 70–73% of total length).

Description.—(1) Maximum SVL in males 72 mm (n = 8); (2) maximum SVL in females 64 mm (n = 5); (3) vertebrals 39–46; (4) paravertebrals 38–46; (5) scales around midbody 32–38; (6) supraoculars 4–5; (7) internasals 2–4; (8) postrostrals 4–6; (9) loreals 1–2; (10) gulars 15–18; (11) subdigitals on Finger IV 17–21; (12) subdigitals on Toe IV 24–28; (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 always visible through interparietal cornea; (16) scales on occipitoparietal region small, smooth, juxtaposed or weakly imbricate; (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) antehumeral and oblique neck folds present; (22) lateral and dorsal nuchals similar in size; (23) posterior gulars cycloid, smooth, slightly imbricate, notched; (24) lateral and dorsal body scales similar in size; (25) vertebrals and adjacent paravertebrals similar in size; (26) dorsolateral crest absent; (27) ventrals smooth, imbricate; (28) scales on posterior surfaces of thighs granular; (29) inguinal granular pocket absent; (30) inguinal groove absent; (31) preanals not projected; (32) tail not compressed laterally in adult males; (33) tail length 70–73% 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 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 life.—Dorsum dark brown with scattered pale yellow irregular marks in males and a faint dorsolateral light stripe in females; dorsum of head, neck, and lateral aspect of neck with bright yellow spots in males; dorsal aspect of limbs with pale yellow spots in males; venter cream; yellow transverse band on pectoral region in males; yellow patch on ventral aspect of pelvic region, thighs, and base of tail in males, this patch partially retained in some females.

Distribution.— Stenocercus modestus inhabits the Pacific lowlands and slopes of the western Cordillera of the central Andes in Peru between 12 ° S–11 ° S ( Fig. 12 ). This species occurs in the valley of Río Rimac (Pacific drainage) at elevations of 0–762 m in Departamento Lima ( Fritts, 1974; Laurent, 1984).

Figures

FIG. 20.—Eight species of Stenocercus. (A) S. marmoratus (AMU); (B) S. melanopŋgus (PVE); (C) S. modestus (MLU); (D) S. nigromaculatus (WED); (E) S. nubicola (PVE); (F) S. ochoai (WED); (G) S. orientalis (PVE); (H) S. ornatissimus (MLU).

FIG. 12.—Distribution of six species of Stenocercus in Peru. Black triangle pointed by arrow corresponds to María Teresa (10°42'05"S, 75°27'22"W, 1470 m, Departamento Pasco), where Stenocercus boettgeri, S. formosus, S. scapularis, and S. torquatus occur in sympatry.