Stenocercus qalaywasi, Venegas & García-Ayachi & Chávez-Arribasplata & García-Bravo, 2022

Venegas, Pablo J., García-Ayachi, Luis A., Chávez-Arribasplata, Juan C. & García-Bravo, Antonio, 2022, Four new species of polychromatic spiny-tailed iguanian lizards, genus Stenocercus (Iguania: Tropiduridae), from Peru, Zootaxa 5115 (1), pp. 1-28 : 19-23

Stenocercus qalaywasi sp. nov.

Figures 8–9

Holotype. CORBIDI 20567 , adult male from Lampa Pariahuanca , Pariahuanca district , Huancayo province, Junín Department, Peru (11°58’51.9”S, 74°53’47.6”O, 2,587 m), collected by Luis A. García-Ayachi on 19 June 2019.

Paratype. CORBIDI 20568 , an adult female collected with the holotype .

Diagnosis. From all currently known species of Stenocercus (including the new species described herein), S. qalaywasi sp. nov. is only similar to thirteen species (e.g., S. asenlignus sp. nov., S. arndti , S. flagracanthus , S. leybachi sp. nov., S. bolivarensis , S. carrioni , S. chlorostictus , S. crassicaudatus , S. empetrus , S. eunetopsis , S. nigrocaudatus sp. nov., S. torquatus and S. simonsii ) in sharing the following characters: granular scales on posterior surface of thighs, relatively short tail, caudals spinose, and two caudal whorls per autotomic segment. From these species, S. qalaywasi possesses a smaller number of vertebrals than S. nigrocaudatus and S. torquatus (77–79 in S. qalaywasi versus 96–108 in S. nigrocaudatus and 83–115 in S. torquatus ), scales on dorsal surface of neck keeled (granular in S. asenlignus , S. nigrocaudatus and S. torquatus ), a longer tail than S. asenlignus , S. nigrocaudatus and S. torquatus (tail length 57–60% of total length in S. qalaywasi , 51–55% in S. asenlignus , 50–55% in S. nigrocaudatus , and 47–54% in S. torquatus ). Stenocercus leybachi is easily distinguished from S. qalaywasi by having a distinct, serrate, low crest on neck (absent in S. qalaywasi ) and by lacking a distinct, black antehumeral collar (complete middorsally in S. qalaywasi ).

Stenocercus arndti , S. crassicaudatus , S. empetrus , S. flagracanthus , and S. simonsii can also be easily distinguished from S. qalaywasi by having the scales on dorsal surface of neck granular, while in the new species they are keeled. Furthermore, S. crassicaudatus and S. flagracanthus possess more vertebrals (83–97) than S. qalaywasi (77–79). In the case of S. flagracanthus , the tail is shorter (50–54% of total length) than S. qalaywasi (57–60%). Species such as S. bolivarensis , S. carrioni , S. chlorostictus , and S. eunetopsis possess keeled scales on the dorsal surface of neck, like S. qalaywasi , and preserved specimens can be confused. However, these species can be distinguished by the following features: from S. arndti , S. carrioni , S. chlorostictus , S. empetrus , and S. simonsii by having a distinct black, middorsally complete, antehumeral collar and two nuchal bands (antehumeral collar incomplete middorsally and nuchal bands absent in the aforementioned species); from S. carrioni and S. chlorostictus by having more vertebral scales (55–72 in S. carrioni , 63–73 in S. chlorostictus and 77–79 in S. qalaywasi ); from S. bolivarensis by having the lateral scales of body granular (strongly keeled in S. bolivarensis ); and from S. eunetopsis by having more scales around midbody (60–80 in S. eunetopsis and 87–92 in S. qalaywasi ) and a shorter tail (57–60% of total length vs. 62–66% in S. eunetopsis ).

Characterization. (1) Maximum SVL in males 88 mm (n = 1); (2) maximum SVL in females 95 mm (n = 1); (3) vertebrals 77–79; (4) paravertebrals 104–108; (5) scales around midbody 87–92; (6) supraoculars six; (7) internasals four; (8) postrostrals six; (9) loreals five; (10) gulars 44; (11) subdigitals on Finger IV 26–29; (12) subdigitals on Toe IV 33–34; (13) posthumeral mite pocket present as one or more vertical folds or ridges [Type 1 of Torres-Carvajal (2007b)]; (14) postfemoral mite pocket distinct with slit-like opening [Type 2 of Torres-Carvajal (2007b)]; (15) parietal eye not visible; (16) scales on occipitoparietal region small, rugose, juxtaposed; (17) projecting angulate temporal absent; (18) row of enlarged supraoculars occupying most of supraocular region absent; (19) scales on frontonasal region juxtaposed, rugose; (20) preauricular fringe present; (21) antegular, antehumeral, gular, longitudinal, and postauricular neck folds present; (22) lateral and dorsal nuchals similar in size; (23) posterior gulars cycloid, smooth, slightly imbricate, not notched; (24) lateral body scales smaller than dorsals, reduced in size, approximately one third of the size of dorsal body scales closer to vertebral line; (25) vertebrals larger than adjacent paravertebrals forming a distinct vertebral row; (26) dorsolateral crest absent; (27) ventrals smooth, imbricate; (28) scales on posterior surface of thighs granular; (29) prefemoral fold present; (30) inguinal groove present; (31) preanals not projected; (32) tail not compressed laterally in adult males; (33) tail relatively short (tail length 57–60% of total length); (34) two caudal whorls per autotomic segment; (35) caudals spinose; (36) dark 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) black patches on ventral surfaces of thighs in adult males absent; (42) background color of dorsum green or dark gray, with distinct black bands in adults individuals of both sexes; (43) postxiphisternal inscriptional ribs not examined.

Description of the holotype. Male ( Fig. 8 ); SVL 88 mm; TL 136 mm; maximum head width 16.8 mm; head length 21.4 mm; head height 13.2 mm; posterior dorsal head scales small, smooth, juxtaposed; parietal eye not visible; supraoculars in six rows, smooth, juxtaposed, with the most lateral two rows less than half the size of the medial adjacent rows; distinct circumorbitals absent; canthals two; internasals four; postrostrals five, two lateral ones larger; supralabials six; infralabials six; loreals four; lorilabials in one row; preoculars two, the dorsal-most in contact with posterior canthal; lateral temporals granular; gulars in 44 rows between tympanic openings; all gulars cycloid, smooth, imbricate, not notched; second infralabial in contact with first two sublabials; first pair of postmentals partially in contact medially; mental in contact with first pair of infralabials but not with the first pair of postmentals; dorsal scales of neck small, weakly keeled, slightly imbricate, and slightly larger than granular laterals; dorsal scales of body imbricate, keeled, becoming smaller, slightly keeled or smooth towards flanks; scales around midbody 87; vertebrals 77, enlarged, keeled, imbricate, forming a distinct vertebral row; paravertebrals adjacent to vertebral row 104, same size or slightly smaller than vertebrals; ventrals smooth, imbricate, larger than dorsals; preauricular fringe short, composed by two enlarged, projected scales; antegular, antehumeral, gular, longitudinal, and postauricular neck folds present; ventrolateral fold present; humeral dorsal scales imbricate, weakly keeled; dorsal scales of forelimbs imbricate, keeled; dorsal scales of hindlimbs imbricate, keeled, mucronate; ventral humeral scales imbricate; ventral scales of forearms keeled, imbricate, and ventral scales of hindlimbs imbricate, smooth; palmars imbricate, keeled; plantars imbricate, keeled, mucronate; lamellae on Finger IV 26; lamellae on Toe IV 33; tail rounded; caudals strongly keeled, mucronate, imbricate dorsally; two caudal whorls per autotomic segment; basal subcaudals strongly keeled, imbricate; posthumeral mite pocket present as one or more vertical folds or ridges [Type 1 of Torres-Carvajal (2007b)]; postfemoral mite pocket distinct with slit-like opening; [Type 2 of Torres-Carvajal (2007b)].

Color in life of holotype ( Fig. 9 A-C): Head bright green with a narrow gray postocular stripe and two gray stripes below it; dorsal surface of neck with two pale gray transverse bands and a distinct, middorsally complete black antehumeral collar; dorsum, limbs and tail with a green hue and scattered dark gray flecks; dorsum and forelimbs also covered by bright green specks; gular region dark gray, spotted with light gray blotches, and bearing a pale gray medial patch posteriorly; ventral surface of neck pale gray; chest greenish gray; belly light pink; ventral surface of hips and hindlimbs cream; cloacal region and ventral surface of base of tail cream with a light pink hue; ventral surface of tail gray becoming dark gray towards tip. Iris brown.

Color in preservative ( Fig. 8 ): dorsal surface dark gray; the postorbital gray stripe black; bands on neck and antehumeral collar black; dorsum with short irregular black bands along the vertebral region and covered with light gray specks; forelimbs covered with light gray specks and hindlimbs with darker bands than the gray background; fingers and toes light gray with black spots. Ventral surface similar as in life, but without the pink and green hues.

Intraspecific variation. Scale counts and measurements for Stenocercus qalaywasi are presented in Table 1 . Loreals 4–5; postrostrals 4–5; second infralabial not in contact with third sublabial in all specimens; first pair of postmentals in contact in both specimens.

Sexual dimorphism is not evident in S. qalaywasi ; the single female paratype ( CORBIDI 20568 ) differs from the male holotype only in having the antehumeral black collar incomplete ( Fig. 9E ). Ventrally, the gular coloration is greenish cream with cream spots laterally in the female paratype ( Fig. 9F ), and dark gray with light gray spots in the male holotype. With a low sample of two specimens, the female is larger (95 mm) than the male (88 mm SVL) .

Distribution and natural history. Stenocercus qalaywasi is known only from the village of Lampa Pariahuanca in the inter-Andean valley of the Mantaro River in central Peru ( Fig. 3 ). It occurs at an elevation of 2,587 m in the department of Junín. The type locality lies within the Peruvian Yungas ecoregion following Olson et al. (2001) and Yungas ecoregion according to Brack-Egg (1986) and Peñaherrera del Águila (1989).

Six individuals of S. qalaywasi were observed basking on sunny days at 0900 hours on the rooftops of Lampa Pariahuanca village houses. When disturbed, they hid under the roof tiles, in holes between bricks or in the slit between roof and wall. The surrounded areas of the village are croplands of corn ( Zea mays ), potato (Solanum tuberosum), carrot ( Daucus carota ), and barley ( Hordeum vulgare ), with a few scattered patches of secondary montane forest on the steepest slopes. No other species of lizards or snakes were recorded at this locality.

When the adult individuals of S. qalaywasi are basking, they possess the head bright green and the dorsal surface of body and tail with a green hue bearing conspicuous light green specks on back ( Fig 9G ). At the moment of capture the single male collected changed dramatically in coloration to dark gray with the dorsum containing light gray specks ( Fig. 9A ). The single collected female specimen did not show a dramatic change of coloration becoming simply dull green ( Fig. 9D ).

Etymology. The specific epithet “ qalaywasi ” is a noun in apposition derived from two words in Quechua, “ qalaywa ” that means lizard and “ wasi ” that means home or house. The specific name refers to the habitus of this species of living in the houses of Lampa Pariahuanca village.

Figures

FIGURE 3. Distribution map of Stenocercus asenlignus sp. nov., Stenocercus leybachi sp. nov., S. nigrocaudatus sp. nov., and S. qalaywasi sp. nov., and the similar species: S. arndti, S. carrioni, S. chlorostictus, S. crassicaudatus, S. empetrus, S. eunetopsis, S. flagracanthus, S. simonsii, and S. torquatus. The symbols of species with a black spot in the centre correspond to type localities. Black dots correspond to important cities for reference.

FIGURE 8. Stenocercus qalaywasi sp. nov. preserved holotype, adult male, SVL 88 mm (CORBIDI 20567): dorsal (A), lateral (B), and ventral (C) views of the head; dorsal (D) and ventral (E) views of the entire specimen. Photographs by LAGA. Scale bar = 10 mm.

FIGURE 9. Dorsolateral and ventral views of Stenocercus qalaywasi sp. nov. in life: (A-C) holotype, SVL 88 mm (CORBIDI 20567); (D-F) adult female, SVL 95 mm (CORBIDI 20568); (G) adult male basking on a roof (not collected). Photographs by LAGA.