Polychrus jacquelinae, Koch, Claudia, Venegas, Pablo J., Garcia-Bravo, Antonio & Boehme, Wolfgang, 2011

Koch, Claudia, Venegas, Pablo J., Garcia-Bravo, Antonio & Boehme, Wolfgang, 2011, A new bush anole (Iguanidae, Polychrotinae, Polychrus) from the upper Maranon basin, Peru, with a redescription of Polychrus peruvianus (Noble, 1924) and additional information on Polychrus gutturosus Berthold, 1845, ZooKeys 141, pp. 79-107 : 80-87

Polychrus jacquelinae sp. n.

Holotype.

CORBIDI 7725 (Fig. 1 A–E, 2A, B), an adult male from a new road, that was still under construction and is intended to connect San Vicente/Pusaq and Uchumarca (06°59'S, 77°54'W, approximately 1460-1570m above sea level), Province Bolivar, Región de La Libertad, Peru, collected by W.A. Garcia Bravo on 01 July 2010.

Paratypes.

CORBIDI 5742 (Fig. 2D) and CORBIDI 7724, two adult females collected with the holotype; ZFMK 91763 (Fig. 2C) subadult male and ZFMK 90834, ZFMK 91764 (Fig. 2E) two adult females from the type locality, collected by W.A. Garcia Bravo and C. Koch on 24 April 2009.

Diagnosis.

(Tab. 1). (1) A Polychrus with a maximum known snout-vent-length (SVL) of 144 mm; (2) dorsal and gular crests absent; (3) 131 to 186 scales around midbody; (4) 198 to 215 scales in middorsal row from behind the occipital scales to the level of the posterior edge of the thigh; (5) femoral pores 13 to 15 on one side; (6) lamellae on finger IV 33-36; (7) lamellae on toe IV 42-48; (8) tail 2.13-2.33 times SVL; (9) dorsal and ventral scales small and smooth (10) a prominent sexual dichromatism present.

Polychrus jacquelinae sp. n. differs from other species of Polychrus by having more than 130 scales around midbody and more than 198 scales in middorsal row from behind the occipital scales to the level of the posterior edge of the thigh ( Polychrus acutirostris has fewer than 73 and 126 scales; Polychrus femoralis fewer than 100 and 156; Polychrus gutturosus fewer than 81 and 105; Polychrus liogaster fewer than 95 and 125; Polychrus marmoratus fewer than 90 and 118; and Polychrus peruvianus fewer than 74 and 70 (paravertebrals), respectively). Furthermore, the new species is easily distinguished from Polychrus acutirostris and Polychrus femoralis by the absence of keeled ventral scales; from Polychrus gutturosus by the absence of multicarinate ventral scales and by the presence of very small gular scales; from Polychrus liogaster and Polychrus marmoratus by the presence of a sexual dimorphism in colouration (absent in the two latter species); and from Polychrus peruvianus by the absence of vertebral and gular crests.

Description of holotype.

Adult male with a snout-vent-length (SVL) of 140.5 mm. Head 0.25 times SVL, 1.51 times longer than wide, as wide as high. Snout pointed; canthus rostralis distinct posteriorly. Neck narrower than the head, and almost as wide as the anterior part of the body. Body compressed. Limbs well developed, forelimbs 0.41 times SVL, hindlimbs 0.53 times SVL, tibia 0.17 times SVL. The tail almost round in cross section, tapering toward the tip; 2.22 times SVL. Rostral trapezoid, almost two times as wide as high, visible from above. Posterior margin with 3 sutures that do not partition the rostral, bordered posteriorly by 2 large scales. Scales on snout heterogeneous in size, irregularly polygonal, juxtaposed, flat, rugose, some are swollen; 3 scales across snout between second canthals. 3 canthals between nasal and supraciliaries, anterior one wide. Supraorbital semicircles more or less distinct, with 9-10 scales, separated medially by 1 row of scales, slightly smaller in size than those of supraorbital semicircles (Fig. 1A). Scales on supraocular region distinctly smaller than those on snout, polygonal to rounded, juxtaposed, flat, and smooth, irregularly arranged, except for a row of smaller scales adjacent to supraciliaries. Supraciliaries 12-13, juxtaposed, smooth, anterior ones slightly longer; in a continuous series with canthals. 15 supraoculary scales on the dorsal surface of the orbit counted in a transverse line across its greatest width. Scales on parietal region, irregular polygonal, some almost rounded, juxtaposed, flat, smooth, intermediate in size between those on snout and on supraocular region. Scales on interparietal region polygonal, juxtaposed, rugose, some are somewhat swollen. Parietal eye absent. Loreal region with two scales. Nostril directed laterally, in the centre of a single nasal. Nasal in contact with second supralabial. 5 internasals. Eye diameter 0.18 times as long as head length. Eyelids partially fused, covered by granules of almost same size throughout the eyelids. A continuous series of 2 preoculars, 3-4 suboculars, which are in direct contact with supralabials, and 4 postoculars. Supralabials 7; followed to commissure of mouth by 1-2 relatively small scales. Temporal region with polygonal or rounded, juxtaposed, flat, and smooth scales, smaller toward the ear opening; delimited dorsally by a single row of enlarged supratemporal scales. Ear opening vertically oval, with smooth margin; tympanum superficial (Fig. 1B).

Mental bell-shaped, almost 2.5 times as wide as high, posterior half divided by a median sulcus. Postmentals 3, lateral ones distinctly larger than median scale. Infralabials 6; followed to commissure by 2-3 distinctly smaller scales. Lateral scales on chin almost the same size as those on median part of chin, irregular polygonal, juxtaposed, flat, smooth, and slightly convex. No elevated scales on the median part of chin and gular region present. Gular fan has scales the same size and structure as chin scales, which are separated from each other by an extensible skin covered with granules (Fig. 1C). Gular fan reaches level of forelimbs. 73 gular scales in transverse line between the two tympani.

Scales on nape anteriorly relatively small, granular and almost rounded, juxtaposed, convex; posteriorly grading into dorsals. Scales on the sides of the neck are slightly larger than those on the nape, merging ventrally with the gulars. Dorsals polygonal to rounded, juxtaposed, flat, to some extent convex; 198 scales in a middorsal line between the occiput and the posterior margin of the hindlimbs. Scales on flanks are of a similar size and same shape as those of dorsum, convex, smooth, in poorly defined, oblique rows. Ventrals larger than dorsals, flat, smooth, lanceolate, and imbricate, in poorly defined, oblique and transverse rows. A gradual transition between dorsal, lateral and ventral scales. Scales around midbody 186. Preanal plate has scales which are smaller than ventrals, approximately the same size as dorsals. Preanal pores absent. Femoral pores 14 per side, almost in the centre of a slightly larger scale (Fig. 1E).

Tail has rhomboid, flat, sharply keeled scales, distinctly larger than the dorsals, arranged in longitudinal and oblique rows; keels aligned longitudinally; on ventral surface of the tail, scales are slightly larger and more rectangular. Tail not regenerated ending somewhat bluntly.

Scales on forelimbs slightly larger than dorsals, polygonal to rounded, flat, smooth, mostly imbricate but more juxtaposed on upper arm; slightly smaller on ventral aspect of forearms; towards posterior aspect ventrals become smaller. Scales on hindlimbs are as large as dorsals, polygonal to rounded, flat, smooth, imbricate on thigh and ventrally, juxtaposed on dorsal surface of tibia, slightly larger and slightly keeled on ventral part of tibia, and slightly lanceolate; toward posterior aspect of thighs, both dorsally and ventrally, scales become distinctly smaller. Subdigital lamellae of fingers and toes single, short, multicarinate, 35 under fourth finger, 47 under fourth toe (Fig. 1D).

Measurements of holotype (in mm).

Snout-vent length 140.5; axilla-groin length 64; length of leg 74; length of arm 58; length of tail 311.5; body height at midbody 25.3; body width at midbody 22.4; length of head 35.7; height of head 23.4; width of head 23.7; length of snout 25; diameter of eye 6.3; distance from tip of snout to anterior margin of nostril 7.1; distance from nostril to eye 7.9; distance from eye to ear 14.

Colouration of holotype.

In life, when unstressed (Fig. 2A), the dorsal surface of the head of the male holotype is grey to greenish-grey on the snout and the parietal region, muddy yellow on the frontal region and more or less shiny yellow on the supraocular region. Most of the dorsal head scales as well as the dorsal body scales have dark edges. The sides of the head are white to slightly yellow. The granules on the eyelids and the scales surrounding the eye are shiny yellow. The dorsum is pale grey, and in some parts fades to a pale yellow or pale green with hardly any special markings, except for some slightly darker saddle blotches. The body parts above and behind the insertion of the front legs are almost as shiny yellow as the granules of the eyelids. The dorsal surface of the limbs is pale grey-green and of the tail white-grey. The tail is ringed with 12 darker grey bands, with each band being 10-13 scales in width, and thus of the same width as the ground coloured interspaces. The bands are indistinct at the beginning but become more distinct towards the tip. The chin scales, gular fan, venter and ventral surface of the limbs are white.

Under stress (Fig. 2B), colouration of whole body changes into a moderate grey, being the darkest in the middorsal region. Colouration grades laterally into beige, especially behind the limbs, with darker, frazzled, transverse stripes on the dorsum and limbs.

The species may also change its colours to camouflage itself, but this behaviour was not observed during our short investigation.

In preservative, the general dorsal colour is mainly brown-grey and the head and middorsal stripe are darker than the lateral body parts. Bands on the tail alternate in pale brown-grey and dark grey-brown. The ventral region is white to pale grey.

Variation.

(Tab. 1) Female paratypes (n=4) reach a maximum SVL of 144 mm and a maximum tail length of 306 mm. Tails of paratypes (n=5) are 2.13-2.33 times SVL and axilla-groin lengths are 0.48-0.55 times SVL. Heads reach 0.23-0.25 times SVL, are 1.46-1.63 as long as they are wide and 0.98-1.1 times as wide as they are high. Eye diameter is 0.17-0.23 times the head length. Scales around the midbody vary between 131-149 and the vertebral scale number from behind the occiput to the level of the posterior edge of the thigh varies between 202-215. The rostral scale is posteriorly bordered by 2-4 scales and exhibits 1-4 posterior sutures that do not completely divide the rostral. There are three scales across the snout between the second canthals. There are three to four canthals between the nasal and the superciliaries. The supraorbital semicircles consist of 9-10 scales, and are separated medially by one to two rows of scales. Superciliaries 9-13 and supraocularies 13-17. In 4 paratypes, the nasal was in contact with the second supralabial, and in one specimen it was separated from the labials by small scales.

There is a continuous series of 2-4 preoculars, 3 suboculars, which are in direct contact with the supralabials, and 3-4 postoculars. Supralabials 5-7; followed to commissure of mouth by 1-4 scales. Internasals in all paratypes 5. Supratemporals 6-7.

Mental half divided by a median sulcus in three paratypes, almost divided in one paratype and completely divided in another specimen. Postmentals 4 in all paratypes. Gular scales 72-83. Infralabials 6-8; followed to commissure by 2-6 scales. Femoral pores 13-15 per side. Subdigital lamellae 33-36 under fourth finger, 42-48 under fourth toe.

Colour variation.

In life, the dorsal surface of the head of the subadult male paratype (ZFMK 91763, Fig. 2C) is pale grey-green on the snout and frontal region, grey-blue in the parietal region and pale green-yellow on the supraocular region. Most dorsal head scales as well as dorsal body scales have dark edges. The sides of the head are pale green-grey to white in the region anterior to the eye, and pale peach-coloured in the temporal region. There is a dark stripe from the posterior margin of the eye, reaching below the supratemporals to the level of the ear opening. The labials and suboculars are mostly white and the dorsum is pale mint green with 6 brown to peach-coloured saddle blotches, 16-29 scales in width, being widest on the middorsal part and tapering towards the flanks. The dorsum is spotted black. There is a mint colour grading into pale peach-colour on the sides of the neck and flanks. The dorsal surface of the forelimbs is mint green and of the hindlimbs, it is peach-coloured intermixed with some mint scales. Both front and hindlimbs are spotted black. The ground colour of the tail is pale beige with 12 darker brownish bands, 10-18 scales in width. The venter, chin scales, gular fan, and limbs are white to whitish-grey.

In life, the dorsal ground colouration of females (CORBIDI 5742, CORBIDI 7724, ZFMK 90834, ZFMK 91764) on the head, back, limbs and tail is lime green with most parts spotted black (Fig. 2D); granules of eyelids are shiny yellow to lime green (Fig. 2E); sides of head posteriorly of eye between supratemporals and the beginning of the gular fan in some of the specimens are intermixed with numerous blue toned scales; dorsum has 5-6 undulated transversal black bands, 2-6 scales in width, first band on level of forelimbs, is continued on the limbs, last one on level of hindlimbs; bulges of the undulated black lines are anteriorly filled with bluish blotches, 3-5 scales in width; posteriorly, the black bands are followed by darkly shaded green stripes, 12-20 scales in width; followed by ground colour, 8-10 scales in width; adjacent starts the repetition of the whole pattern, beginning with the bluish blotches, followed by the undulated transversal black band; tail with 12 darkly shaded greenish bands, 9-12 scales in width and of almost same width as ground colour interspaces. On ventral surface, chin scales and gular fan are shiny yellow, and in some parts, spotted with white (Fig. 2E); one gravid female (ZFMK 91764) has pale green chin scales and pale orange gular fan. Venter and limbs are white; tail white to whitish-grey annulated with darker grey bands, indistinct at the beginning but becoming more distinct towards the tip. No colour changes were observed in the female specimens of this species.

In preservative, dorsal pattern remains similar to the pattern in life but colouration mainly consist of different shades of blue, only the darkly shaded green stripes on the dorsum are brownish-blue to brown in some of the specimens; head grey-blue to greenish-blue; on tail brownish to greyish-brown bands, alternating with pale greyish-brown, pale green or blue toned bands. On ventral surface, gular fan, venter, limbs and tail white to greyish-white; chin also white to greyish white, but in one gravid specimen (ZFMK 91764) it is intermixed with pale bluish scales.

Etymology.

The species is dedicated to Jacqueline Maria Charles (Leicester, England) in recognition of her support of nature conservation and taxonomic research through the BIOPAT initiative.

Distribution and natural history.

This new species is only known from the type locality (Fig. 3) in the inter-Andean valley on the western slope of the northern portion of the Cordillera Central (see Duellman and Pramuk 1999), at an elevation of 1460 to 1570 m above sea level. All individuals were collected near a road between San Vicente/Pusaq and Uchumarca (06°59'S, 77°54'W), Province Bolivar, Región de La Libertad, Peru. Polychrus jacquelinae inhabits the equatorial dry forest eco-region in the upper Marañón basin, fide Brack (1986). One subadult male (ZFMK 91763) and two females (ZFMK 90834, ZFMK 91764) were found on 24 April 2009 between 9.45 p.m. and midnight, sleeping in trees of Acacia macracantha in heights between 1.8 m and 5 m above the ground, at an air temperature of 22°C and a humidity of 63%. One adult male (CORBIDI 7725) and two adult females (CORBIDI 5742, CORBIDI 7724) were found on 01 July 2010 between 7.30 p.m. and 8.30 p.m., sleeping, at an air temperature of 25°C and a humidity between 34-38%, in a bush of Fabaceae sp. approximately 2 m above the ground, in a bush of Croton sp. approximately 4 m above the ground, and in a tree of Bombax sp. approximately 3.5 m above the ground, respectively. One female (ZFMK 91764) was gravid and contained 6 oval eggs (3 in each of the oviducts). On average, these eggs had a length of 27.7 mm and a width of 15.8 mm.