Cyrtopodion baigii, Masroor, Rafaqat, 2008

Masroor, Rafaqat, 2008, A new species of Cyrtopodion (Sauria: Gekkonidae) from the northern areas of Pakistan, Zootaxa 1857, pp. 33-43 : 34-39

Cyrtopodion baigii sp. nov.

Figs. 1–9

Holotype: An adult male, PMNH 1965, collected just before sunset, from rocky foothills of the Khanbari Valley, Diamer Basha Dam Reservoir, Chilas, Astor District, Northern Areas, Karakoram Range, Pakistan (35º33'57''N, 73º50'29''E), at an elevation of 1181m ( Fig. 3 ) by Khalid Javed Baig on 6 July 2007.

Paratypes: PMNH 1966, 1967 and 1968 were collected from rocky foothills of the Kiner Valley, Diamer Basha Dam Reservoir, Chilas, Chilas, Astor District, Northern Areas, Karakoram Range, Pakistan (36º 27'32''N, 74º25'37''E), at an elevation of 1175m ( Table 1 ) by Khalid Javed Baig on 8 July 2007.

Diagnosis: Medium sized geckos; tail longer than body; 16–18 interorbital scales; body dorsum with prominent, moderate sized, trihedral tubercles, not in contact with each other, arranged in 10 longitudinal rows, 28 paravertebral rows extending from immediately behind occiput to level of vent; 30–32 rows of ventral scales across midbody; 125–132 scales along ventral midline of body; males with two preanal pores, femoral pores absent; tail clearly segmented, each segment dorsally with three rows of small, heterogeneous subtrihedral scales anteriorly, becoming trihedral posteriorly.

Description of the Holotype: Habitus depressed; head relatively long (HL/SVL ratio 0.28), not wide (HW/HL ratio 0.63) and depressed (HH/HL ratio 0.32), distinct from slender neck. Snout elongate (SE/HL ratio 0.39) and pointed. Eyes not large (OD/HL ratio 0.17); pupil vertical with crenellated margins; supraciliaries short, bearing tiny conical spines posteriorly. External auricular opening small (EL/HL ratio 0.07), oval and vertical; eye to ear distance more than diameter of eye (EE/OD ratio 1.39). Rostral scale rectangular, broader than high, incompletely divided by a median furrow, bordering the nostril; 3 pairs of postrostrals separated by a series of small scales; nostrils small, oval or round, bordered by 3 nasals, rostral, and first supralabial; height of suture between first supralabial and rostral scale subequal or slightly shorter than the length of former along jaw margin; supralabials 11/11, first longest, posteriormost smallest; infralabials 8/8, first three about equal in size, last followed by three tubercles; head covered with heterogeneous tubercular scales; a patch of larger keeled preocular tubercles; top of the head with intermixed hexagonal tubercles, those on the supraorbital region flat and largest of all; 11 tuberculated loreal scales between anterior border of orbit and upper nasal scale; preorbital and postnasal area shallow; 16 rows of heterogeneous interorbital scales; frontal, preorbital and post-narial area of head concave with relatively smaller scales; canthus indistinct, loreal region concave. Trunk slightly flattened and elongate (TRL/SVL ratio 0.40), its dorsal surface covered with small granular to weakly conical scales, among which are regularly distributed rounded, smooth scales; dorsum with 10 longitudinal rows of medium-sized trihedral tubercles, those of 6 most median rows enlarged and distinctly trihedral, those of 2 lateralmost rows of each side subtrihedral and slightly irregular in arrangement; each enlarged tubercle surrounded by 11–12 and separated by 1–3 juxtaposed, heterogeneous, flat, granular scales; 28 dorsal tubercles in paravertebral row extending from immediately behind head to level of vent.

Mental scale large, pentagonal; three pairs of postmentals, first large, in contact behind mental for more than one half length of mental scale, second postmental more than half the size of the first one, third smallest, about one fourth size of second; genial scales small, hexagonal, slightly imbricate; abdomen with flat, squarish sub-imbricate scales, larger than dorsals, in 30 rows across midventer; 130 scales along midventral line of body from postmental suture to anterior margin of vent; lateral abdominal scales small, juxtaposed, in 3–4 rows; gular region with relatively homogeneous, smooth scales; 2 weakly developed preanal pores, transversely enlarged, in large, squarish scales equal in size to surrounding poreless scales ( Fig. 7 ); femoral pores absent, femoral scales enlarged.

Limbs of moderate length, when maximally extended forward, tips of fingers hardly reaching between nostril and eye; tips of toes of adpressed hindlimbs extend to base of neck; digits somewhat elongate; digit IV of manus with 17 and digit IV of pes with 23 subdigital lamellae, those on basal part of the digits broader than on compressed distal portion; claws present on all digits, small, curved, needle sharp; dorsum of limbs with large, keeled, flattened imbricate scales; scales of limb venter heterogeneous, broader, smooth, those at joints small; upper arm with small, slightly imbricate scales, underside of forearm with large smooth, imbricate scales; dorsum of thigh with large, keeled, tubercular scales, underside with large smooth scales in seven to eight rows; tibia dorsum with trihedral tubercles, larger than dorsal trihedral tubercles, separated by small granular scales, underside with large imbricate scales.

Tail longer than body, slightly depressed, gently tapering to tip, segmented, each segment with 3 rows of small heterogeneous scales in a transverse row of six large mucronate scales, three on each side, their keels directed outward, separated by 2–3 smaller scales from one another; tail fragile ; anterior of tail with 7–8 smaller subcaudals in a transverse row, more posteriorly two rows subcaudals, each longer than broad.

Color: Dorsum light gray in life with dark brown speckling arranged in 9 distinct M-shaped cross bands; small dark spots on the head and transverse bands on the limbs; tail with 10 dark brown bands on dorsum. Body venter and undersides of head and limbs white to off white, with scattered pigment extending from dorsum onto lateralmost scales.

Etymology: The species epithet is a patronym honoring the late Dr. Khalid Javed Baig for his contributions to the knowledge of the herpetofauna of Pakistan.

Variation: Variation in morphometric data and pholidosis is presented in Table 1 . There is no significant variation among the members of the type series of Cyrtopodion baigii except for the absence of precloacal pores in females.

Distribution and Habitat: The type locality is a part of the reservoir of the proposed Diamer Basha Dam located on the Indus River, about 40 km downstream of Chilas city in Northern areas of Pakistan, and is a component of the Chilas Arc Complex. The new species constitutes the first record of a species of Cyrtopodion from the Karakoram Range, Pakistan. Extremes of temperatures are experienced during the winter and summer seasons. Historical maximum temperature of 48.1 o C was observed at Chilas on 1st August 1983 and minimum temperature of -4.4 o C was observed on 15th January 1967. The area around Chilas generally receives very low precipitation resulting in minimal vegetation except in isolated patches where tributaries join the Indus. The whole reservoir area can be differentiated into five kinds of distinct sub-habitats: rocky habitat with steep slopes, flat rocky areas covered by stones, sandy flats covered by stones, wind blown sandy deposits, and areas of farmland and human settlement, each with its specific associated herpetofauna.

Cyrtopodion baigii inhabits rocky habitats devoid of vegetation cover on steep slopes ( Fig. 1 ), which occur all along the length of the reservoir on either side of the Indus River. Plant species recorded in the area are small xerophytic shrubs or under-shrubs. Dominant among these are Artemisia dubia , A. maritema , and Heliotropium dasycarpum . Solanum surratense, Tribulus terrestris, Chrozophora plicata, Zizyphus sativa and Echinops sp. are rarer plants in this habitat type. No larger tree or shrub species are present and grazing pressure is very low.

Diet: Analysis of gut contents shows that Cyrtopodion baigii is exclusively insectivorous and feeds on ants, beetles, termites and dipterans.

Figures

FIGURE 1. Rocky habitat with steep slopes at the type locality of Cyrtopodion baigii, sp. nov.

FIGURE 2. Living specimen of Cyrtopodion baigii, sp. nov. in its typical rocky habitat.

FIGURE 3. Map of the Diamer Basha Dam reservoir area of northern Pakistan.

FIGURE 7. Preanal pores of the Holotype PMNH 1965.

Tables

TABLE 1. Mensural and meristic data for the type specimens of Cyrtopodion baigii sp. nov. Only variable meristic features presented, see description for condition of invariant characters. All measurements in mm. * = holotype.

Characters PMNH No. 1965*	PMNH No. 1966	PMNH No. 1967	PMNH No. 1968
Body Habitus Depressed	Depressed	Depressed	Depressed
Sex Male	Female	Female	Male
Head length (HL) 13.0	11.3	11.3	13.1
Head width (HW) 8.3	7.5	7.0	8.5
Head Height (HH) 4.2	4.2	4.2	4.4
Snout-eye distance (SE) 5.1	4.5	4.4	5.1
Orbital Diameter (OD) 2.3	2.1	2.1	2.4
Ear Length (EL) 1.0	0.9	0.8	1.0
Ear-Eye Distance (EE) 3.2	3.2	3.0	3.3
Trunk Length (TRL) 19.0	16.4	16.3	18.6
Snout-Vent Length (SVL) 46.5	41.0	39.2	44.4
Tail Length (TL) 58.6	48.1	44.4	54.0
Interorbital Scales 16	18	16	18
Scales around dorsal tubercle 12	11	11	12
Mid-Ventrals 130	125	130	132
Scales across belly (Mid-Abdominals) 30	30	30	32
Precloacal Pores 2	-	-	2
Lamellae under Digit IV Pes 22	22	23	25
Lamellae under Digit IV Manus 17	15	16	15