Stenocercus prionotus Cadle

Stenocercus prionotus Cadle, 1998:187 . Holotype: USNM 193683, a male from ‘‘ Jardín Botánico de la Universidad Agraria de La Selva, Tingo María, vicinity of Río Huallaga, 9 ° 18'S, 75 ° 59'W, 670 m, Departamento Huánuco, Perú ̕̕.

Diagnosis.—Among species of Stenocercus with strongly keeled ventrals and laterally oriented nostrils, S. prionotus is similar to S. aculeatus, S. angulifer, S. caducus, S. fimbriatus, and S. scapularis in having a distinct posthumeral mite pocket. Of these species, only S. caducus, S. fimbriatus, and S. prionotus lack a postfemoral mite pocket. Furthermore, S. prionotus and S. caducus are unique in having an axillary flap covering the antehumeral mite pocket (Cadle, 2001). S. prionotus can be distinguished from S. caducus by having two projecting angulate temporals (projecting angulate temporals absent in S. caducus), and by having a more prominent vertebral crest.

Description.—(1) Maximum SVL in males 89 mm (Cadle, 2001); (2) maximum SVL in females 93 mm (Cadle, 2001); (3) vertebrals 27–39; (4) paravertebrals 42–54; (5) scales around midbody 36–48; (6) supraoculars 4–7; (7) internasals 5–8; (8) postrostrals 4–7; (9) loreals 3–5; (10) gulars 15–22; (11) subdigitals on Finger IV 16–21; (12) subdigitals on Toe IV 24–31; (13) posthumeral mite pocket present as a deep depression covered by an axillary flap; (14) postfemoral mite pocket absent; (15) parietal eye always visible through interparietal cornea; (16) scales on occipitoparietal region small, keeled or multicarinate, juxtaposed or slightly imbricate; (17) two projecting angulate temporals; (18) row of enlarged supraoculars occupying most of supraocular region absent; (19) scales on frontonasal region weakly imbricate anteriorly; (20) preauricular fringe inconspicuous or absent; (21) neck folds absent; (22) lateral and dorsal nuchals similar in size; (23) posterior gulars rhomboidal, projected posteriorly, strongly keeled and imbricate, not notched; (24) lateral and dorsal body scales similar in size; (25) vertebrals much larger than adjacent paravertebrals; (26) dorsolateral crest absent (but see Cadle, 2001); (27) ventrals keeled, imbricate, mucronate; (28) scales on posterior surfaces of thighs keeled, imbricate; (29) inguinal granular pocket absent; (30) inguinal groove absent; (31) preanals projected; (32) tail strongly 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 present; (37) dark patch extensively covering gular region of females absent; (38) dark patch extensively covering gular region in 7% of adult males; (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 continuous midventrally, Patterns 6A and 7 (KU 212629 and KU 179058 misidentified by Torres-Carvajal [2004 a] as Stenocercus aculeatus and S. tricristatus, respectively, correspond to S. prionotus .)

Color in life (males only).—Dorsum brown with white vertical line on shoulder; dorsum of head with dark brown interorbital line; dark brown stripe extending anterodorsally from subocular region to supraciliaries; ventrolateral aspect of body between limbs lavenderbrown; gular region streaked by light cream lines; midventral aspect of body between limbs tan brown (Cadle, 2001).

Natural History.—A female (KU 179058, SVL = 88 mm) collected in January 1969 in Departamento Huánuco contained two oviductal eggs. Sizes of these eggs are 26.65 mm X 12.49 mm and 27.97 mm X 12.34 mm; their volumes are 2176.8 mm 3 and 2230.1 mm 3, respectively. The smallest juvenile (USNM 247680) was collected in October 1983 and has a total length of 111 mm (SVL = 35, TL = 76). Most specimens of S. prionotus have been collected in open areas including disturbed habitats and light gaps within forests (Cadle, 2001).

Distribution.— Stenocercus prionotus occurs between 15 ° S–6 ° S in the eastern Cordillera and adjacent lowlands of the central Andes (Fig. 13). This species is known from Bolivia (Departamentos Beni and La Paz) and Peru (Departamentos Huánuco, Loreto, Madre de Dios, Puno, San Martín) at elevations of 176–1520 m (Cadle, 2001). S. prionotus is sympatric with S. fimbriatus (Peru: Loreto), S. roseiventris (Peru: Madre de Dios, Huánuco, Puno), and possibly S. aculeatus in northern Peru (Cadle, 2001).