Dravidogecko septentrionalis, Chaitanya & Giri & Deepak & Datta-Roy & Karanth, 2019

Chaitanya, R., Giri, Varad B., Deepak, V., Datta-Roy, Aniruddha & Karanth, Praveen, 2019, Diversification in the mountains: a generic reappraisal of the Western Ghats endemic gecko genus Dravidogecko Smith, 1933 (Squamata: Gekkonidae) with descriptions of six new species, Zootaxa 4688 (1), pp. 1-56 : 17-20

Dravidogecko septentrionalis sp. nov.

( Figs 7 A–D, 13F, 14A; Table 5 )

Hemidactylus anamallensis: Bauer & Russell, 1995

Hemidactylus anamallensis [non Gecko anamallensis Günther, 1875 ] — Philip, Arjun & Joy, 2011; Bansal & Karanth, 2013.

Holotype. BNHS 2340 , an adult male, Lakkidi village (11.5184°N, 76.0451°E; ca. 873 m asl.), Wayanad District , Kerala, collected by B.H.C.K Murthy and RC on 27 th November, 2016.

Paratypes. Details of collection same as the holotype. BNHS 2341 , BNHS 2342 , BNHS 2344 , ZSIK 2971 , ZSIK 2972 , ZSIK 2975 adult females; BNHS 2343 , ZSIK 2973 , ZSIK 2974 adult males.

Type locality. Lakkidi village, Wayanad District, Kerala.

Summarized description and diagnosis. Snout-vent length up to 56.9 mm (n=10); internasals separated by 2 smaller scales; two pairs of well-developed postmentals, inner pair slightly longer than the outer, briefly in contact with each other behind mental, bordered by mental, infralabial I, outer postmentals and 2 or 3 gular scales. ventral scales counted at midbody, 30–35; precloacofemoral pores, 52–56 (n=4); subdigital lamellae under digit IV of manus, 7–10 and under digit IV of pes, 10–13; supralabials, 8–10 and infralabials, 7–10 on each side.

Dravidogecko septentrionalis sp. nov., though closely allied to D. anamallensis , can be easily distinguished from the latter by the presence of a greater number of precloacofemoral pores, (PcFP 52–56 versus 45 or 46), a greater number of ventral scales ( VS 30–35 versus 25–28) and number of scales between the internasals (two versus one).

Genetic divergence (p-distance). Dravidogecko septentrionalis sp. nov. exhibits 0.3% intraspecific variation, and is 5.0–6.5 % divergent from D. anamallensis ( Table 9 ).

Description of holotype. The holotype is in good condition ( Fig 7A ). Body is dorsoventrally flattened with the second toe and second finger on the right curved upwards, both artefacts of preservation. Distal portion of the tail is regenerated, slightly curved towards the right. Hemipenis everted, exposed and seen on both sides when viewed dorsally. Adult male, SVL 55.9 mm. Head short (HL/SVL 0.28), slightly elongate (HW/HL 0.67), not depressed (HH/HW 0.66), distinct from neck. Loreal region slightly inflated, canthus rostralis indistinct ( Fig 7C ). Snout short (SE/HL 0.40), longer than orbital diameter (OD/SE 0.67); scales on snout, canthus rostralis, inter-orbital region, forehead, occipital and nuchal regions granular and rounded with those on the snout and canthus rostralis being larg- er and flat ( Fig 7B ). Eye small (OD/HL 0.26); pupil vertical with crenulated margins; supraciliaries small, roughly triangular, pointed upwards and gradually increasing in size anteriorly. Ear opening elliptical (longer diameter 0.7 mm); eye to ear distance slightly longer than diameter of eye (EE/OD 1.16). Rostral wider than deep (RL/RW 0.40), without a distinct rostral groove; two large internasals, separated by two smaller scales of similar size, all in broad contact with rostral; two postnasals on either side, slightly smaller than the internasals, the lower in contact with supralabial I; rostral in contact with nasal, supralabial I, internasals and the two small scales separating the internasals; nostrils about the size of the lower postnasal, roughly circular with nasal pad visible posteriorly; nasal surrounded by internasal, rostral, supralabial I and two postnasals on either side; 2–4 rows of scales separate orbit from supralabials at mid-orbital position. Supralabials roughly rectangular, increasing in length anteriorly. Supralabials (to midorbital position) 7 (right), 8 (left); supralabials (to angle of jaw) 9 (right), 10 (left); infralabials (to angle of jaw) 7 (right), 8 (left). Mental triangular; two pairs of well-developed postmentals, the inner pair slightly shorter (1.1 mm) than the mental (1.3 mm), and in contact with each other (0.2 mm) behind mental; outer pair shorter (0.8 mm) than the inner pair, separated from each other by three gular scales that are only slightly smaller than postmentals ( Fig 7D ). Inner postmentals bordered by mental, infralabial I, outer postmentals and three smaller gular scales; outer postmentals bordered by infralabials I (barely touching on left side) and II, inner postmentals, and four (right) and three (left) smaller gular scales each of dissimilar sizes. Body relatively slender, elongate (TRL/SVL 0.48). Dorsal pholidosis composed of small, flat, rounded scales that are juxtaposed in arrangement, homogeneous in shape, becoming slightly larger laterally; Ventral scales larger than dorsals, largely homogeneous in shape and size, smooth, sub-imbricate; gular region with smaller, granular, juxtaposed scales; anterior gular scales visibly larger, flatter; scales on femoral region larger than those on sacrum and chest with some precloacal scales being largest; midbody scale rows across belly 30–32. Non-lamellar scales in the palmar and plantar regions flat and smooth; ones on palm juxtaposed while those on sole sub-imbricate and weakly pointed; scales on dorsal aspect of upper arm larger than granules on dorsum, sub-imbricate and smooth; dorsal aspect of forearm with smaller, sub-imbricate scales intermixed with a few rounded granules around the elbow; scales on dorsal aspect of hand and digits larger than those on forearm, flat, weakly pointed and imbricate; scales on dorsal part of thigh and shank heterogeneous in size, flat, weakly pointed and sub-imbricate; largest on anterior aspect of thigh. Scales on dorsal aspect of foot larger than those on shank, flat, rounded and imbricate.

Forearm (FL/SVL 0.11) and tibia (CL/SVL 0.12) short; digits moderately short with relatively long terminal phalanges, 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, more than half as long as associated toepad; scansors beneath each toe undivided throughout, in a straight transverse series: 6-7-8-7-7 (left manus), 7-7- 8-9-7 (right manus), 7-8-9-10 -8 (left pes), 6-8-10-10 -8 (right pes). Relative length of digits (measurements in mm in parentheses): IV (4.5)> III (4.1)> V (4.0)> II (3.8)> I (2.9) (left manus); III (5.6)> IV (5.2)> II (5.1)> V (4.8)> I (3.3) (left pes).

Tail long (TL/SVL 1.18), rounded at the base, flat beneath, tapering posteriorly with the distal portion regenerated, covered above uniformly with smooth, flat, rounded, sub-imbricate scales, larger than those on dorsum, becoming slightly enlarged laterally; subcaudal scales larger, with an undivided median series of enlarged scales that continue until the regenerated portion. An uninterrupted series of 54 precloacofemoral pores that are indistinct towards the knee ( Fig 13F ).

Variation in paratypes. Rostral groove distinct and extends halfway through the scale in BNHS 2342 , BNHS 2343 , ZSIK 2971 , ZSIK 2974 and ZSIK 2975 . Inner postmentals in BNHS 2341 in contact with infralabial I and II. Two gular scales border the inner postmentals posteriorly in BNHS 2341 , BNHS 2342 , BNHS 2344 , ZSIK 2971 , ZSIK 2973 , ZSIK 2974 and ZSIK 2975 . Outer postmentals bordered by 3 gulars on the right and 4 on the left in ZSIK 2975 , 4 gulars on either side in BNHS 2342 and ZSIK 2971 , and 3 gulars on either side in ZSIK 2974 . Outer postmentals in contact only with infralabial II in ZSIK 2973 (L) and ZSIK 2974 (L). Other morphological variations are listed in Table 5 .

Colour in preservative. Dorsum uniformly greyish-brown mottled with darker, discontinuous streaks from the snout to the base of tail ( Fig 7A ). Similar mottling visible on dorsal aspect of limbs. Occipital region with three distinct longitudinal streaks. Snout slightly darker than rest of the body with scattered, vague, dark-brown markings. Labials paler than rest of the head and similar to the rest of the dorsum. Supralabials bordered by a discontinuous dark brown streak from nostril to eye. Limb colouration no different from rest of the dorsum. The original portion of tail interspersed with alternating light and dark bands while the regenerated portion, mid-brown. Venter predominantly cream with scattered patches of diffusely pigmented scales on head and cloacal regions. Ventral surface of tail pale, with scattered mid-brown speckling throughout until the regenerated portion, which is predominantly mid-brown.

Colouration (in life). Dorsal markings distinct in life ( Fig 14A ). Dorsum mid-brown with darker streaks throughout. Head dorsum ground colour, snout slightly darker and with a pale border. A pale streak in the supraocular region, following the contour of the skull and extending beyond forehead, bordered by a dark streak on each side emanating from just behind the eye and up to the forehead. A dark spot on the head just anterior to the occipital region, followed by another at the occiput, the latter flanked on either side by dark, streaks curved outwards. A dark streak just posterior to the occipital region also flanked by dark, curved, discontinuous lines. Seven irregular, roughly transverse markings follow, until the sacral region. Each marking flanked by dark irregular spots. Limbs of ground colour with irregular dark spots. Tail regenerated; distinctly banded with alternating light and dark portions up to the regenerated portion.

Etymology. The specific epithet is an adjective in the nominative case derived from the Latin for ‘northern’, referring to the distribution of this species to the north of the Palghat Gap.

Suggested Common name. Wayanad Dravidogecko .

Distribution. Dravidogecko septentrionalis sp. nov. is presently restricted in distribution to Lakkidi village in Wayanad District, Kerala. Isolated hills in the Wayanad region with a similar altitude (ca. 900 m asl) could potentially harbour other populations. A population from the Nilgiris district of Tamil Nadu is likely to be closely allied with D. septentrionalis sp. nov. (pers obs).

Habitat and natural history. The type-series of Dravidogecko septentrionalis sp. nov. was collected from outer compound walls of buildings in Lakkidi village in the western part of the Wayanad plateau. The abutting vegetation is predominantly mid-elevation evergreen forests that get ca. 3500mm– 6000mm of annual rainfall ( Anu & Sabu 2007). They were found only in areas that were above 850 m asl and seem to be restricted to isolated hillocks with conducive ecological conditions. None of the female specimens encountered during the survey in November 2016 were gravid. A large bodied Cnemaspis sp. and Hemidactylus cf. frenatus were found in sympatry.

Figures

FIGURE 7. Holotype of D. septentrionalis sp. nov. A) Full-body dorsal B) Head dorsal C) Head lateral D) Head ventral. Scale bar = 10 mm.

FIGURE 13. Cloacal region showing precloacofemoral pores (indicated by black dots) in the congeners of Dravidogecko. A) D. anamallensis B) D. douglasadamsi sp. nov. C) D. smithi sp. nov. D) D. meghamalaiensis sp. nov. E) D. janakiae sp. nov. F) D. septentrionalis sp. nov. G) D. tholpalli sp. nov. Scale bar = 10 mm

FIGURE 14. A) Dravidogecko septentrionalis sp. nov. (BNHS 2344) in life, from Lakkidi village, Wayanad, Kerala B) Dravidogecko meghamalaiensis sp. nov. (BNHS 2347) in life from Meghamalai, Theni, Tamil Nadu C) Dravidogecko douglasadamsi sp. nov. (uncollected specimen) from Manjolai estate, Tirunelveli, Tamil Nadu

Tables

TABLE 5. Measurements (in mm) and scale counts for the specimens of Dravidogecko anamallensis and D. septentrionalis sp. nov. Abbreviations as in Materials and Methods. * indicates tail is regenerated, #—broken tail and + indicates a bifid tail tip. Numbers in parentheses indicate the supralabial at midorbital position.

	Dravidogecko anamallensis			Dravidogecko septentrionalis sp. nov.
Tag	1946.8. 23.61	ZSIK 2969	ZSIK 2970	BNHS 2340	BNHS 2341	BNHS 2342	BNHS 2343	BNHS 2344	ZSIK 2971	ZSIK 2972	ZSIK 2973	ZSIK 2974	ZSIK 2975
Status	Holotype	Topotype	Topotype	Holotype	Paratype	Paratype	Paratype	Paratype	Paratype	Paratype	Paratype	Paratype	Paratype
Sex	♂	♀	♀	♂	♀	♀	♂	♀	♀	♀	♂	♂	♀
Measurements
SVL	44.8	54.1	51.5	55.9	56.9	50.6	45.9	56.5	55.6	53.5	52.0	53.1	56.0
TRL	21.2	25.1	24.2	27.0	28.1	24.2	22.0	28.2	28.4	26.6	25.3	26.4	27.9
BW	8.9	12.4	11.0	10.9	11.7	10.1	9.9	11.1	11.1	9.5	10.6	10.6	10.3
CL	6.8	7.1	7.0	6.9	6.7	6.5	6.2	6.8	6.8	7.2	6.8	6.9	6.8
TL	29.6+	-	58.7	66.0	70.6	60.7	19.5#	42.5#	59.7*	66.2	59.1*	51.8 #	52.7*
TW	5.1	-	4.7	4.8	5.0	4.6	4.7	4.9	5.0	4.8	4.5	5.0	4.7
HL	12.4	13.0	12.8	13.7	14.0	12.8	12.3	13.7	13.8	13.7	13.6	13.9	13.4
HW	8.7	9.2	8.9	9.0	9.4	8.3	8.2	9.0	9.4	9.2	9.4	9.4	9.0
HH	5.0	5.1	5.2	5.4	5.3	4.7	4.5	5.4	5.5	5.0	5.2	5.5	5.2
FL	5.7	5.8	5.6	6.2	6.3	6.0	5.6	6.3	6.3	6.4	6.1	5.4	6.2
OD	2.5	3.5	3.2	3.6	3.5	3.1	3.1	3.5	3.5	3.3	3.3	3.6	3.3
NE	3.9	4.1	3.6	4.3	4.2	3.9	3.9	4.3	4.3	4.2	4.1	4.2	4.1
SE	5.2	5.3	5.0	5.4	5.3	4.8	4.9	5.5	5.2	5.2	5.2	5.3	5.3
EE	3.8	4.0	3.8	4.2	4.1	3.8	3.6	4.0	3.9	3.6	4.0	3.6	4.0
IN	1.9	2.0	2.1	1.9	2.1	1.8	1.7	2.0	1.8	2.1	2.1	1.9	1.7
IO	5.8	5.9	5.8	5.6	6.1	5.0	5.3	5.7	6.1	5.3	5.9	5.7	5.6
EL	1.7	1.1	0.8	0.7	0.7	0.8	0.7	0.5	1.1	1.0	0.8	0.6	0.9
RW	2.0	2.1	2.0	2.3	2.3	1.9	2.1	2.2	2.5	2.3	2.4	2.2	2.2
RL	0.7	0.8	0.8	0.9	0.9	0.8	1.0	0.8	0.7	0.8	0.9	0.9	0.7
ML	1.2	1.3	1.1	1.3	1.3	1.0	1.2	1.3	1.4	1.0	1.0	1.0	1.3
MW	2.1	2.2	1.8	1.8	2.0	2.0	1.7	1.7	2.0	1.9	1.7	1.9	1.8
CT	1.2	0.8	0.2	0.2	0.8	0.8	0.6	0.4	0.3	0.5	0.4	0.7	0.7
1PML	1.6	1.6	1.5	1.1	1.3	1.4	1.3	1.1	1.3	1.1	1.4	1.2	1.2
2PML	1.4	1.2	0.6	0.8	0.9	1.0	0.9	0.9	0.8	0.9	0.9	0.8	0.8
Meristics
PcFP	45	NA	NA	54	NA	NA	52	NA	NA	NA	56	55	NA
VS	25-26	27-28	26-27	30-32	34-35	32-33	34-35	34-35	30-31	30-32	30-32	30-32	32-33
Lam (I-V)
Forelimb (L)	6-7-8-8-7	5-8-8-9-7	6-8-8-9-8	6-7-8-7-7	7-8-8-9-8	7-8-8-9-7	6-8-8-8-7	7-8-9-7-7	7-8-8-8-7	7-8-9-8-8	6-7-7-7-7	7-7-9-10-7	7-8-9-10-8
Forelimb(R)	5-8-8-8-7	6-8-8-10-7	6-8-8-9-8	7-7-8-9-7	7-8-8-9-7	7-8-8-8-7	6-8-9-8-7	7-8-9-7-7	7-7-7-7-7	7-8-9-9-7	7-7-7-7-7	6-7-9-8-7	6-8-8-10-7
Hindlimb (L)	6-9-9-12-7	6-9-9-12-9	5-9-9-12-7	7-8-9-10-8	7-9-10-11-8	7-8-9-10-7	6-8-10-12-7	7-10-10- 11-8	7-8-10- 10-8	6-9-10-13-8	7-9-9-11-7	7-9-9-10-8	8-10-11-13-8
Hindlimb(R)	6-9-7-11-7	6-9-9-12-8	6-8-9-12-8	6-8-10-10-8	7-9-9-12-8	6-8-10-11-7	6-9-10-11-8	7-9-10-11-8	6-8-9-10-7	8-10-10-12-8	7-9-10-11-8	6-9-10- 11-8	7-9-10-11-8
SL(L/R)	12(8)/11(8)	9(8)/10(7)	9(7)/10(8)	10(8)/9(7)	9(7)/10(7)	10(8)/9(7)	10(8)/9(7)	9(7)/10(8)	9(8)/9(7)	10(7)/10(7)	10(8)/10(8)	8(7)/9(7)	10(8)/9(7)
IL(L/R)	8/8	8/8	7/7	8/7	8/9	8/8	7/8	8/10	8/7	8/9	7/8	8/8	8/7