Hemidactylus sushilduttai, Giri & Bauer & Mohapatra & Srinivasulu & Agarwal, 2017

Giri, Varad B., Bauer, Aaron M., Mohapatra, Pratyush P., Srinivasulu, Chelmala & Agarwal, Ishan, 2017, A new species of large-bodied, tuberculate Hemidactylus Oken (Squamata: Gekkonidae) from the Eastern Ghats, India, Zootaxa 4347 (2), pp. 331-345 : 332-341

Hemidactylus sushilduttai sp. nov.

Figs. 1–7

Hemidactylus maculatus (non Duméril & Bibron, 1836) Smith 1935; McCann 1945: 435 Hemidactylus maculatus maculatus (non Duméril & Bibron, 1836) Javed et al., 2010 Hemidactylus cf. maculatus Mirza & Sanap 2014

Holotype. NCBS-AU157 , adult male; Simhachalam , Visakhapatnam District, Andhra Pradesh, India (17.767° N 83.248° E), collected by Aparna Lajmi, Aniruddha Datta-Roy and V. Deepak, 0 1 April 2014.

Paratypes. ESV 109 , adult male, near Lambasingi , Visakhapatnam District, Andhra Pradesh, India (17.798° N, 82.502° E, 750 masl), collected by Aniruddha Datta-Roy, V. Deepak, Ishan Agarwal and Prudhviraj, 0 6 October 2014 ; ESV 110, adult female, Maredumilli , East Godavari District, Andhra Pradesh (17.443° N 81.753° E), same collectors as holotype, 29 March 2014 ; ESV 111, subadult male, ESV 112 and ESV 113, adult females, same collection data as holotype. NCBS-AU160 , adult female, near Ananthagiri , Visakhapatnam District, Andhra Pradesh, India (18.255° N, 82.991° E, 1170 masl), 18 September 2013, collected by Aniruddha Datta-Roy, Ishan Agarwal and Tarun Khichi .

Diagnosis. A large sized Hemidactylus , snout-vent averaging 91.9 ± 13.3 mm (n=6) and up to at least 105.0 mm. Dorsal pholidosis heterogeneous, composed of granular scales intermixed with 16–17 fairly regularly arranged longitudinal rows of enlarged, strongly keeled, trihedral tubercles at midbody. First supralabial in contact with nasal; two well-developed pairs of postmentals, the inner pair slightly larger than the outer pair and in contact behind the mental. Ventrolateral folds indistinct, 30–33 scale rows across venter. All digits with enlarged scansors, 11–12 (manus) and 11–13 (pes) divided lamellae beneath fourth digit and 9–11 (manus) and 9–11 (pes) beneath first digit; 21–24 femoral pores on each side separated by four poreless scales in males. Original tail depressed, oval in transverse section with a median dorsal furrow; scales on the dorsal aspect of tail heterogenous, slightly larger than granular scales on dorsum, weakly imbricate, intermixed with a longitudinal series of six to eight, enlarged, strongly keeled and pointed tubercles. Dorsal coloration of transversely arranged, pale grey to ashy markings on a pale mustard-brown background.

Hemidactylus sushilduttai sp. nov. can be easily distinguished from most congeners from India, Sri Lanka and Pakistan based on its heterogenous dorsal pholidosis that consists of small granules intermixed with 16–17 rows of fairly regularly arranged, longitudinal rows of distinct, pointed trihedral tubercles at midbody versus H. aquilonius Zug & McMahan , H. garnotii Duméril & Bibron and H. platyurus (Schneider) , which all have homogenous dorsal pholidosis of small granules without enlarged tubercles; H. imbricatus Bauer, Giri, Greenbaum, Jackman, Dharne & Shouche and H. scabriceps (Annandale) , which have homogenous dorsal pholidosis with imbricate scales and no enlarged tubercles; H. albofasciatus Grandison & Soman , H. gracilis Blanford , H. reticulatus Beddome and H. sataraensis Giri & Bauer which have heterogenous dorsal pholidosis with irregularly arranged indistinct tubercles; H. frenatus Duméril & Bibron , H. leschenaultii Duméril & Bibron , and H. flaviviridis Rüppel , which either lack enlarged tubercles or have small rounded tubercles mainly on the flanks; and H. gujaratensis Giri, Bauer, Vyas & Patil which has 12–16 rows of irregularly arranged, flattened to weakly conical dorsal tubercles.

The large size of Hemidactylus sushilduttai sp. nov. (up to 105.0 mm SVL) easily distinguishes it from the smaller sized, tuberculate congeners H. brookii Gray , H. chipkali Mirza & Raju , H. depressus Gray , H. gleadowi Murray , H. kushmorensis Murray , H. lankae Deraniyagala , H. murrayi Gleadow 1887 , H. parvimaculatus Deraniyagala , H. persicus Anderson , H. pieresii Kelaart , H. robustus Heyden , H. tenkatei Lidth de Jeude , H. treutleri Mahony , H. triedrus (Daudin) , and H. turcicus (Linnaeus) , all of which reach maximum sizes of 90 mm SVL or less.

A number of congeners in India and Sri Lanka approach or exceed maximum sizes of 100 mm, including H. aaronbaueri Giri 2008 , H. acanthopholis , H. giganteus Stoliczka , H. graniticolus , H. hemchandrai Dandge & Tiple , H. hunae Deraniyagala, H. maculatus Duméril & Bibron , H. prashadi Smith , and H. yajurvedi Murthy, Bauer, Agarwal, Lajmi & Giri. Hemidactylus sushilduttai sp. nov. can be diagnosed from all large-bodied Indian and Sri Lankan congeners by the number and shape of enlarged dorsal tubercles (16–18 rows of fairly regularly arranged, longitudinal rows of distinct trihedral tubercles at midbody) and number and arrangement of femoral pores (20–23 femoral pores separated by 3–6 poreless scales) (opposing character states indicated parenthetically): H. giganteus (complete absence of enlarged dorsal tubercles), H. yajurvedi and H. hemchandrai (10–15 rows of irregularly arranged, slightly larger, rounded, weakly-keeled tubercles at midbody), H. prashadi (14–16 rows of enlarged subtrihedral tubercles and 17–20 femoral pores on each side separated by three poreless scales), H. hunae (16–20 relatively regular rows of keeled, subtrihedral tubercles and 22–24 femoral pores on each side with a gap of 3–6 scales), H. graniticolus (16–18 relatively regular rows of subtrihedral, weakly keeled, striated tubercles and 23–28 femoral pores on each side separated by 1–3 poreless scales), H. maculatus (20 relatively regular longitudinal rows of large trihedral tubercles and 15–19 femoral pores on each side with a gap of 5–6 poreless scales), H. acanthopholis (18–20 relatively regular longitudinal rows of trihedral, moderately keeled, striated tubercles and 19–21 femoral pores separated by 13–14 poreless scales).

Description of the holotype. The holotype is generally in good condition with some exceptions related to preservation ( Fig. 1 ). The head is slightly bent to the left and the tail is fixed in a curl toward the right. There is an 11 mm long incision in the sternal region (for tissue collection), a ventrolateral fold of skin on the right side running from neck to mid-body and a ventrolateral fold on the left from behind the eye up to the neck. There is a slight constriction near the groin caused by a field tag and the venter is flattened as an artifact of preservation.

Head short (HL/SVL ratio 0.29), slightly elongate (HW/HL ratio 0.75), not strongly depressed (HH/HL ratio 0.45), distinct from neck ( Fig. 2 A ). Loreal region slightly inflated, canthus rostralis not prominent. Snout short (SE/HL ratio 0.40); more or similar to eye diameter (OD/SE ratio 0.50); scales on snout, canthus rostralis granular and pointed, 2–3 times larger than those on interorbital and occipital region, occipital region has intermixed enlarged, keeled, pointed tubercles, which are 3–4 larger than adjacent granules. Eye small (OD/HL ratio 0.20); pupil vertical with crenulated margins; supraciliaries small, pointed, those at the anterior end of orbit slightly larger, posterior half with smaller spinose scales. Ear opening oval (greatest height 3.2 mm); eye to ear distance slightly greater than diameter of eye (EE/OD ratio 1.5). Rostral wider (3.9 mm) than deep (2.9 mm), incompletely divided dorsally by weakly developed rostral groove; internasals separated by a single small scale, one supranasal and one postnasal on each side, all subequal; rostral in contact with nostril, supralabial I, internasals and scale separating the internasals; nostrils large (1.1 mm), subcircular, each surrounded by supranasal, internasal, rostral, supralabial I and postnasal; 4–5 rows of scales separate orbit from supralabials, single row of enlarged elongate scales bordering supralabials ( Fig. 2 B ). Mental triangular, broader (4.3 mm) than high (4 mm), two pairs of postmentals, inner pair slightly shorter (3.3 mm) than mental and in extensive contact with each other (1.5 mm) behind mental ( Fig. 2 C ); outer post mental small (1.8 mm), medially divided. Inner postmentals bordered by mental, infralabial I and II, outer postmentals and 12 gular scales; outer postmentals bordered by inner postmental, infralabial II and 7–8 much enlarged gular scales on either side, of which outer row continues as a single row of enlarged scales below infralabials. About 2–7 rows of scales below infralabials III to VIII are enlarged and weakly imbricate. Supralabials (to midorbital position) 8; supralabials (to angle of jaw) 11; infralabials (to angle of jaw) 8 (right)–9 (left).

Body relatively stout, not elongate (TRL/SVL ratio 0.39), with indistinct ventrolateral folds without denticulate scales. Dorsal pholidosis heterogeneous, composed of conical, granular scales intermixed with enlarged, relatively regularly arranged, longitudinal rows of 16–17 trihedral, strongly keeled tubercles at midbody ( Fig. 3 ), extending from occiput onto the tail, each enlarged tubercle roughly 4–7 times longer than adjacent granules, surrounded by 10–18 small granules, 2–4 granules separate adjacent enlarged tubercles; enlarged tubercles similar in size except those on most medial parasagittal rows less than half the size of adjacent tubercle; shape of enlarged tubercles on back homogenous except those on flanks conical; enlarged tubercles on nape slightly smaller and more conical than those of back; tubercles on occipital and temporal region still smaller, strongly pointed. Ventral scales larger than dorsal granules, smooth, imbricate, slightly larger on femoral and largest on precloacal region; midbody scale rows across belly 33; gular region with granular scales that are smaller than ventrals. Femoral pores 23 on left thigh and 21 on right thigh, with left and right series separated by a diastema of four un-pored scales ( Fig. 4 ).

Scales on the palm and sole smooth, granular, rounded; dorsal aspect of manus and pes heterogenous, granular with densely packed enlarged tubercles, upper arm with a few granular scales which are larger than granules on dorsum intermixed with much larger tubercles; dorsal aspect of forearm predominantly bearing much larger, flattened, strongly keeled tubercles; scales on elbow are strongly keeled and conical, slightly smaller than the enlarged tubercles on the upper arm; those on dorsal aspect of thigh heterogeneous with a few granular scales which are similar to those on dorsum, intermixed with much larger trihedral tubercles which are slightly larger than enlarged dorsal tubercles; tubercles on the back of the thigh much smaller, conical and sparsely spaced; large trihedral tubercles on dorsal aspect of shank slightly smaller than those on dorsum of thigh, intermixed with a few granular scales; scales on knee are strongly weakly keeled and conical, ~ 2 times larger than adjacent granules. Fore- and hind limbs relatively short, stout; forearm short (FL/SVL ratio 0.14); tibia short (CL/SVL ratio 0.15); digits moderately short, strongly clawed; all digits of manus and digits I–IV of pes indistinctly webbed; terminal phalanx of all digits curved, arising angularly from distal portion of expanded lamellar pad or scansor, half or more than half as long as associated toepad; lamellae beneath each toe in straight transverse series, divided except for three to four basal scansors on digit I and single distal on all digits and some single basal ones too; scansors from proximal most at least twice diameter of palmar scales to distalmost single scansor: 10-11-11-12-11 (right manus; Fig. 5 A ), 9-11-12-11-11 (right pes; Fig. 5 B ). Relative length of digits (measurements in mm in parentheses): IV (8.5)> III (8.1)> V (8)> II (7.5)> I (7) (right manus); III (9.5)> IV (9.4)> V (8.6)> II (8.5)> I (6.5) (right pes). Tail depressed, flat beneath, verticillate, with well-defined median furrow; length of the original tail slightly longer than snout-vent length (TL/SVL ratio 1.24); scales on the tail subimbricate, slightly conical and keeled, larger than granules on dorsum, with a series of 6-8 much enlarged, strongly pointed and keeled conical tubercles, lateral row on both sides slightly elongated and weakly keeled ( Fig. 6 A ); ventral scales enlarged, imbricate, median row (subcaudal plates) covering almost entire base of the tail with two rows of larger pointed, smooth, imbricate scales on lateral aspects ( Fig. 6 B ).

Coloration (in preservative). Overall specimen in preservative appears pale with indistinct transverse markings on dorsum and tail. Dorsum grayish- brown with darker speckling (darker small dots) on granular scales and enlarged tubercles throughout, a slightly darker vertebral stripe and a series of still darker, transverse markings, defining the edges of somewhat paler bands (weakly evident on occiput, one across shoulders, one between fore- and hindlimb insertions, and one on sacrum) ( Fig. 1 ) Crown of head similar to dorsum, except slightly darker pigmentation on snout. A thin, dark brown stripe extending from behind nostril to front of orbit, bordered above with lighter stripe, continuing behind eye and on to temporal region. Infralabials and posterior supralabials slightly pale, anterior supralabials with scattered dark pigment. Limbs similar in colour to dorsum with slightly dark pigmentation on dorsal aspects of digits. Tail similar colour to dorsum but becoming paler posteriorly. Venter cream with dark speckling on all scales throughout; palms and soles grayish. Ventrolateral surfaces of tail darkly pigmented, with scattered speckling throughout, more evident on proximal portions and distal portions of midventral scutes.

Colouration (in life). Dorsum with a series of broad transverse bands, one across shoulder, two between fore and hind limb insertions, and one over anterior sacral region; dorsal ground colour russet with paler transverse bands, borders of light bands slightly wavy or scalloped, with narrow seal brown, almost black edging ( Fig. 7 ). Dark edging lacking and division between background coloration and light bands indistinct on flanks. Dorsum of head tawny, without any mottling. Incomplete, very thin greyish occipital band, discontinuously associated with whitish stripe on side of head; supraciliaries yellowish. Basal regions of limbs mottled tawny and grayish, with elbows and knees predominantly light and distal portions of limbs slightly darker; limbs without any prominent markings or bands. Tail banded, with predominant colours as on body dorsum except that pale bands tend towards a lighter ashy colour. Six pale bands on tail, all narrower than adjacent russet bands. Iris a deep golden color.

Juvenile coloration similar to that of the adult, although darker areas are chocolate brown, light bands with yellowish border, limbs are slightly paler, and pale tubercles on the flanks, limbs, head and tail-base are maize yellow rather than dull whitish as in adults. Pale markings distal to the pygal portion of the tail are white, with all but the basal most very bright white. Darker bands on the tail grade from dark brown basally to nearly black at the tip. A total of nine pale bands on the original tail.

Etymology. The specific epithet is a patronym honoring Sushil Kumar Dutta for his contributions to research on Indian amphibians and reptiles, as well as for his central role in encouraging many young herpetologists through talks, workshops, and the dedicated School in Herpetology. The name is particularly apt as the new species is endemic to the Eastern Ghats, the region in which much of S.K. Dutta’s herpetological research has been.

Suggested common name. Dutta’s Mahendragiri Gecko/ Hemidactyl

Variation and additional information from type series. Mensural data for the type series is given in Table 1. The three males and three females range from 55.0 mm to 105.0 mm SVL. All paratypes resemble the holotype in most of the morphological characters except as follows: Range of supralabials is from 9–13 (8–9 below eye) and infralabials from 9–10. The scales across belly range from 30–33 in the paratypes. Range of subdigital lamellae on first digit 9–10 and on fourth digit 1 1–13.

continued.

Distribution and Natural History. The type series of Hemidactylus sushilduttai sp. nov. is from the eastern slopes of the northern Mahendragiri Range and scattered coastal hills ( Fig. 8 ). This species was found in degraded deciduous forests on the coastal hills, and in degraded and intact deciduous forest and coffee plantations at the Mahendragiri Hills; in association with either large boulders or large trees. The species is known from below 250 m close to the coast at Simhachalam to above 1,100 m at Araku. These large, nocturnal geckos are scansorial, found on large boulders and large trees, as well as culverts and occasionally buildings. The skin is fragile and is easily torn. The species is relatively common where it occurs, with most nights of survey effort in areas with large rocks or trees resulting in at least one sighting, and up to more than 10. Sympatric geckos at the type locality include Hemidactylus parvimaculatus Deraniyagala and Cyrtodactylus cf. nebulosus (Beddome).

Molecular data. A partial cytochrome b sequence of topotypical Hemidactylus sushilduttai sp. nov. (ESV 112 GenBank MF668228 ) is 15.9–21.8 % divergent from published sequences of members of the prashadi clade ( Table 2). Importantly, the new species is>16% divergent from Hemidactylus maculatus , H. graniticolus and H. prashadi ; other large-bodied, tuberculate members of the H. prashadi group.

1 2 3 4 5

1 Hemidactylus sushilduttai sp. nov. ESV 112 ( MF668228 )

2 Hemidactylus aaronbaueri ( HM595640 ) 20.2

3 Hemidactylus graniticolus ( HM595663 ) 18.8 22.3

4 Hemidactylus maculatus ( HM559607 ) 15.8 17.3 15.5 5 Hemidactylus prashadi ( HM595668 ) 18.1 23.9 15.7 15.4 6 Hemidactylus triedrus ( HM559616 ) 15.6 20.4 17.4 13.1 15.5

Figures

FIGURE 1. Dorsal view of Hemidactylus sushilduttai sp. nov. holotype, NCBS-AU 157: Photo by Varad Giri & Akshay Khandekar. Scale bar = 10 mm.

FIGURE 2. Head of Hemidactylus sushilduttai sp. nov. holotype, NCBS-AU 157: A) dorsal view, B) lateral view, C) ventral view. Photos by Varad Giri & Akshay Khandekar. Scale bar = 10 mm.

FIGURE 3. Details of dorsal pholidosis of Hemidactylus sushilduttai sp. nov. holotype, NCBS-AU 157, showing irregularly arranged longitudinal rows of enlarged, trihedral tubercles at midbody. Photo by Varad Giri & Akshay Khandekar. Scale bar = 10 mm.

FIGURE 4. Precloacal region of Hemidactylus sushilduttai sp. nov. holotype, NCBS-AU 157 showing series of 11 femoral pores on left and right side separated medially by eight pore-less scales. Photo by Varad Giri & Akshay Khandekar. Scale bar = 10 mm.

FIGURE 5. A) ventral view of right manus and B) ventral view of right pes of Hemidactylus sushilduttai sp. nov. holotype (NCBS-AU 157). Photo by Varad Giri & Akshay Khandekar. Scale bar = 10 mm.

FIGURE 6. Tail of Hemidactylus sushilduttai sp. nov. holotype, NCBS-AU 157: A) dorsal view, B) ventral view. Photo by Varad Giri & Akshay Khandekar. Scale bar = 10 mm.

FIGURE 7. Hemidactylus sushilduttai sp. nov. in life, A) holotype NCBS-AU 157, B) paratype ESV 109. Photos by Ishan Agarwal.

FIGURE 8. Relief map of India and Sri Lanka showing type localities of members of the prashadi clade (Bansal & Karanth 2010) that exceed 90 mm SVL (stars) and the known distribution of Hemidactylus sushilduttai sp. nov. (circles). The imprecise type locality of Hemidactylus acanthopholis (Tirunelveli District) is plotted as the city of Tirunelveli in the map, although this species probably occurs only in the adjacent hills west of the city, with the nearest likely habitat approximately 30 km to the west (Mirza & Sanap 2014).