Stenocercus prionotus Cadle, 2001

Torres-Carvajal, Omar, 2007, A TAXONOMIC REVISION OF SOUTH AMERICAN STENOCERCUS (SQUAMATA: IGUANIA) LIZARDS, Herpetological Monographs 21 (1), pp. 76-178 : 147-148

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).

Figures

FIG. 13.—Distribution of seven species of Stenocercus in South America. Question mark indicates possible distribution of S. tricristatus.