Cyrtodactylus aaronbaueri Purkayastha & Lalremsanga & Bohra & Biakzuala & Decemson & Muansanga & Vabeiryureilai & Chauhan & Rathee 2021, sp. nov.
Creators: name: Purkayastha, Jayaditya
name: Lalremsanga, Hmar Tlawmte
name: Bohra, Sanath Chandra
name: Biakzuala, Lal
name: Decemson, H. T.
name: Muansanga, Lal
name: Vabeiryureilai, Mathipi
name: Chauhan, Suraj
name: Rathee, Yashpal Singh
Publisher: name: Zenodo
Year: 2021
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Reptilia
Squamata
Gekkonidae
Cyrtodactylus
Cyrtodactylus aaronbaueri

description: Cyrtodactylus aaronbaueri sp. nov.
Figs. 7, 8, 11c; Appendix V; Table 2
Holotype. Adult male (MZMU2015), from Durtlang, North (23.797266°N, 92.728791°E; elevation 1285 m asl.), Aizawl District, Mizoram state, northeast India, collected on 17 October 2020 by Lalengzuala Tochhawng and Lal Biakzuala.
Paratypes. Three adult males (MZMU2012, MZMU2021, MZMU2032), from Mizoram University Campus (23.737361°N, 92.667412°E; elevation 840 m asl.), Aizawl District, Mizoram state, northeast India, collected on 2 November 2020 by Lal Muansanga and Ht Decemson; adult female (MZMU2067) and adult male (MZMU2020), from Tamdil National Wetland (23.738656°N, 92.951839°E; elevation 760 m asl.), Saitual district, Mizoram state, northeast India, collected on 20 November 2020 by Ht Decemson, H. T. Lalremsanga, Lal Muansanga and Lal Biakzuala; adult male (MZMU2014), from Zawngtahlipui stream, Sihphir (23.821281°N, 92.750986°E; elevation 840 m asl.), Aizawl district, Mizoram state, northeast India, collected on 12 September 2020 by Ht Decemson and Lalhunthara Chawngthu; two adult females (MZMU2018, MZMU2056), same collection details as holotype (Appendix V).
Definition. Cyrtodactylus aaronbaueri sp. nov. is a moderate-sized gecko (adult SVL 54.2–69.5 mm); 8–11 supralabials; 8–12 infralabials; dorsal tubercles are rounded, conical to weakly keeled and are in 22–28 longitudinal rows; 36–39 paravertebral tubercles; 35–40 mid-ventral scale rows; 7–8 precloacal pores in males; 14–19 subdigital lamellae under toe IV; no single row of transversely enlarged subcaudal scales; 9–11 dark brown blotches on the dorsum of the body often forming a reticulating pattern; original tail with 11–12 alternating dark and light bands.
Description of holotype. Holotype in generally good preservation condition (Fig. 7); tail is complete and preserved with the specimen.
Adult male, SVL 62.0 mm. Head length slightly more than one-quarter of the snout to vent length (HL/SVL 0.27), longer than broad (HW/HL 0.61), somewhat depressed (HD/HW 0.66), and distinct from the neck; loreal region is inflated with granular scales; interorbital region is flat; canthus rostralis broadly rounded; snout is slightly less than half of the head length (SO/HL 0.41) and is almost twice as long as the orbit diameter (OD/SO 0.51); scales on the forehead, canthus rostralis and snout homogeneous. Scales from the posterior margin of the eyes to the nape are slightly smaller than those of the forehead, somewhat blunt and juxtaposed; scales on the interorbital and occipital regions without distinct tubercles. Orbit diameter is slightly more than one-fifth of the head length (OD/HL 0.21); pupil vertical with crenulate margins; supraciliaries small but distinct, somewhat blunt, uniform throughout the orbit, median supraciliaries are the largest, decreasing in size anteriorly and posteriorly the anterior end as well as posterior end of the orbit; ear opening small (EL/HL 0.09) oval, obliquely orientated; eye to ear distance is slightly more than the eye diameter (OD/OE 0.89). Rostral slightly wider than long (RL/RW 0.66), partially divided dorsally by a weakly developed rostral groove; single enlarged supranasal on either side, separated by two small internasals, almost about the same size as enlarged scales on the snout; rostral in contact with the first supralabial, nasals, supranasals and internasals; nostrils semicircular, opening laterally orientated, posterior half covered by the nasal pad, each nasal in broad contact with the rostral and surrounded by a supranasal, first supralabial, and two postnasals; a single row of scales separate the orbit from the supralabials; mental wider than long (ML/MW 0.84), triangular; two well developed postmentals on either side, the inner pair almost twice the size of the outer pair (PMIIL/PMIL:0.59); inner postmentals in contact with the mental, infralabial I, one outer postmental and three gular scales; outer postmental on each side is in contact with one inner postmental, infralabials I and II, and two gular scales; ten supralabials on each side, bordered by a row of slightly elongated scales; ten infralabials on each side, infralabials II to VI bordered ventrally by a row of enlarged gular scales, largest anteriorly; gular region mostly covered with small granular scales except for a few rows bordering the outer postmental and infralabials which are larger, flat and juxtaposed.
Body moderately slender; trunk length is slightly more than half of the snout to vent length (TRL/SVL 0.55); dorsal scales heterogeneous, mostly rounded granular scales, intermixed with irregularly arranged, enlarged tubercles (5–6 times larger than surrounding granular scales), bluntly conical and feebly keeled throughout, becoming more conical and slightly smaller towards the flanks, largest on the presacral and sacral regions; tubercles extend posteriorly from the occipital region to beyond the tail base; tubercles on the nape are smaller than those on the dorsum; 26 mid-body rows of dorsal tubercles; 37 paravertebral tubercles between the level of the axilla and the level of the groin; ventrolateral folds poorly developed with a single row of scattered conical enlarged, smooth tubercles; ventral scales much larger than dorsals, smooth, cycloid, imbricate to subimbricate, largest on the abdomen, slightly smaller under the thighs and on the region anterior to the cloacal opening; 36 mid-ventral scale rows; 8 precloacal pores in a continuous series; three enlarged scales posteriorly bordering the pore-bearing scales are present in a continuous series; postcloacal tubercles present on the tail base, four on the left side and three on the right.
Forearm (FL/SVL 0.15) and tibia (CL/SVL 0.18) short; digits laterally compressed, without a scansorial pad, strongly inflected at each joint, all bearing robust, recurved claws; subdigital lamellae transversely widened beneath the basal phalanx; basal lamellae 4–5–5–5–4 on the right manus, 4–5–5–6–5 on the right pes; distal lamellae (intervening rows of nonlamellar granular scales between basal and distal lamellae series in parentheses): 5(2)– 6(2)–7(3)–7(3)–7(3) on the right manus, 6(3)–7(3)–8 (4)–8(5)–8(4) on the right pes; interdigital webbing absent from both the manus and pes; relative length of digits: I <II <V<III <IV on the right manus, I <II <V <III <IV on the right pes; scales on the palms and soles are smooth, weakly raised, subimbricate; scales on the forelimbs are heterogeneous in size, comprising flat, subimbricate scales on the upper arms, and those on the forearms are heterogeneous in size, ventral portion covered with heterogenous sized imbricate scales; scales on the hindlimbs are heterogeneous in size, on dorsal surfaces of thighs and shanks with large small granular scales, intermixed with scattered, enlarged, conical, feebly keeled tubercles; anterior portion of the thighs and ventral surfaces of hindlimbs with enlarged, smooth, imbricate scales.
Tail (description based on specimen in life: tail preserved along with the specimen), mostly original, complete, slender, gradually tapering from the base towards the tip; poorly developed transverse rows of enlarged, flat, weakly pointed, feebly keeled, tubercles positioned paravertebrally on tail base only (just above the hemipenis), remaining dorsal caudal scales smooth, rounded, subimbricate, similar in size dorsally but becoming larger on lateral aspect; subcaudal scales, smooth, imbricate, forming a mid-ventral series of granular scales; no transversely enlarged subcaudal plates.
Colouration in life (Fig. 8): Dorsum of the head, body and limbs are dark brown; head is primarily dark brown in colour intermixed with a few whitish spots towards the posterior end of the head; a small but distinct white streak is present on the posterior side of both the orbits; nape has a few cream coloured spots on dark brown coloured blotches; dorsum of the trunk exhibits a total of ca. 11 paired dark brown blotches forming a crisscross pattern; middorsal stripe absent. The tail is complete and is having nine distinct dark-brown bands separated by transverse greyish bands. The thigh, hind limbs and forelimbs are primarily dark brown with indistinct cream coloured blotches. Ventral region is off white in colour.
Colour in preservative (Fig. 7; Appendix V). The colour is pale in comparison to the live specimen. The dark spots on the dorsum have turned brownish-black.
Variation. Refer to Table 2 for morphometric and basic pholidosis variation within the type series of Cyrtodactylus aaronbaueri sp. nov. The type series of C. aaronbaueri sp. nov. comprises of six adult males and three adult females. Paratypes MZMU2032 and MZMU2056 have a light dorsal colouration along with a distinct middorsal line running from the nape to the sacral region. All the female paratypes (MZMU2018, MZMU2056, and MZMU2067) have visible pitted scales in their precloacal region (6–8).
Comparison. Cyrtodactylus aaronbaueri sp. nov. is a species of the mountain clade within the south of Brahmaputra clade (see Agarwal et al. 2018). Based on ND2 gene sequence, Cyrtodactylus aaronbaueri sp. nov. showed a p-distance of just 0.016 -0.018 to a sample from near Aizawl, Mizoram (KM255197, Agarwal et. al. 2014) and together is a sister taxa to C. montanus (p-distance: 0.100 -0.105). Morphologically, Cyrtodactylus aaronbaueri sp. nov. can be differentiated from the following species by having a smaller maximum adult size, SVL 69.5, N =9 (versus C. kazirangaensis 80.0 mm, N =3; C. arunachalensis 81.7 mm, N=5; C. ayeyarwadyensis 78.0 mm, N =9; C. khasiensis 81.1 mm, N =7; C. martinstolli 82.0 mm, N =18; C. tamaiensis 90.0 mm, N =1; C. cayuensis 79.78 mm, N =18; C. urbanus 74.0 mm, N =7; C. jaintiaensis 96.2 mm, N =3; C. montanus 78.2 mm, N =5; C. markuscombaii 72.0 mm, N =2); from C. himalayicus by having a larger maximum adult size, SVL 69.5 mm, N =9 (versus 64.5 mm, N =2); from the following species by the presence of non-overlapping PcP number, 7–8, N =9 (versus 10–28 PcP/ PcFP, N =25, in C. ayeyarwadyensis; 10–11 PcP, N =3, in C. kazirangaensis; 10–12 PcP, N =7, in C. khasiensis; 14 PcP, N =2, in C. septentrionalis; 10 PcP, N =2, in C. himalayicus; 5+16 PcP, N =1, in C. mandalayensis; 8 PcP, N =18, in C. martinstolli; 40 PcFP, N =1, in C. tamaiensis; 9–12 PcP, N =7, in C. urbanus; 26–39 PcFP, N =8, in C. guwahatiensis; 8–10 PcP, N =5, in C. montanus; 29–37 PcFP, N =11, in C. tripuraensis; 6–10 PcFP, N = 5 in C. arunachalensis); from the following species by having a higher number of mid-ventral scale rows, 35–40, N =9 (versus 30–34, N =8, in C. guwahatiensis; 30–34, N = 7 in C. urbanus; 34–35, N =2, in C. nagalandensis; 28–34, N =18, in C. cayuensis); from the following species by having a larger number of dorsal tubercle rows, 22–28, N =9 (versus 19–21 rows, N =11, in C. tripuraensis; 21 rows, N =1, in C. tamaiensis; 19–20 rows, N =3, in C. jaintiaensis; 16–18 rows, N =2, in C. nagalandensis; 19–21 rows, N =2,in C. himalayicus; 14–15 rows, N =2, in C. markuscombaii; 18 rows, N =1, in C. mandalayensis); from C. septentrionalis by having a higher number of dark blotches on the dorsum, 9–11, N =9 (versus 6–9, N =2); from the following species by the absence of enlarged plate like subcaudals, N =9 (versus presence of enlarged subcaudals in C. khasiensis, N=7; C. martinstolli, N =18 and C. cayuensis, N =18).
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Distribution and natural history (Fig 1; Appendix VII). The species is currently recorded from localities within Aizawl city area and Tamdil National Wetland, Mizoram state of north-eastern India. All specimens were encountered during night-time surveys. The holotype, and two paratypes (MZMU2056 and MZMU2018) were captured from crevices and clefts of retaining walls nearby human settlements at Durtlang North locality, Aizawl city area. One individual (MZMU2014) was encountered from the streambed adjoining boulder at the Zawngtahlipui stream, Sihphir village. The paratypes (MZMU1067 and MZMU2020) were collected from bryophyte-covered rock walls along the jungle trail in the vicinity of Tamdil lake, Tamdil National Wetland located ca. 86 km road distance towards east from the state capital Aizawl. The Wetland is surrounded by sub-tropical pine virgin forests, endowed with rich herpetofaunal diversity. From this place, a megophryid frog Leptobrachella tamdil was described (Sengupta et al. 2010), Fejervarya multistriata was recorded for the first time in the country (Lalbiakzuala & Lalremsanga 2019a) and recently, the Assam Kukri Snake Oligodon catenatus was rediscovered from the country (Lalbiakzuala & Lalremsanga 2020). The paratype (MZMU2021) and two specimens MZMU2012 and MZMU2032 were captured from a parapet at Lianchhiari road, nearby the Mizoram University (MZU) Guest House, and open jungle track in the MZU Campus, respectively. The area is surrounded by a mixture of secondary and virgin forests. Specimens were usually encountered during monsoon and early post monsoon seasons.
Etymology. The specific epithet aaronbaueri is an eponym honouring Dr. Aaron Bauer for his unparalleled contribution to the field of gekkotan taxonomy. The name is masculine and formed in the genitive case.
Suggested common name. Aaron Bauer’s bent-toed gecko.
description: Published as part of Purkayastha, Jayaditya, Lalremsanga, Hmar Tlawmte, Bohra, Sanath Chandra, Biakzuala, Lal, Decemson, H. T., Muansanga, Lal, Vabeiryureilai, Mathipi, Chauhan, Suraj & Rathee, Yashpal Singh, 2021, Four new Bent-toed geckos (Cyrtodactylus Gray: Squamata: Gekkonidae) from northeast India, pp. 451-489 in Zootaxa 4980 (1) on pages 466-474, DOI: 10.11646/zootaxa.4980.3.2, http://zenodo.org/record/4897011