Cyrtodactylus arnei Do, Ngo, Nguyen, Le, Ziegler, Do & Pham, 2025, sp. nov.

Cyrtodactylus arnei sp. nov. Figs 4, 5 Type material. Holotype. IEBR R.6365 (Field number KH.2020.7), adult male, collected on 26 September 2020 by C. T. Pham on Hon Tre Island (12°12'58.77"N, 109°15'52.44"E; at an elevation of 74 m asl.), Khanh Hoa Province, Vietnam. Paratypes. Five adult males: IEBR R.6366 (Field number KH.2020.5), IEBR R.6367 (Field number KH.2020.8), IEBR R.6368 (Field number KH.2020.11), IEBR R.6369 (Field number KH.2020.12), IEBR R.6370 (Field number KH.2020.13); three adult females: IEBR R.6371 (Field number KH.2020.6), IEBR R.6372 (Field number KH.2020.9), IEBR R.6373 (Field number KH.2020.10), the same data as the holotype. Diagnosis. The new species can be distinguished from other members of the Cyrtodactylus irregularis group by a combination of the following characteristics: size medium (SVL 70.9–78.0 mm); dorsal tubercles in 15–17 irregular rows; 34 or 35 ventral scale rows; 12–15 enlarged femoral scales on each side, in continuous series without gap between precloacal and femoral scales; precloacal pores absent in females, 5–7 in males, in a continuous row; femoral pores absent; postcloacal spurs 0–3 on each side; 19–21 lamellae under toe IV; dorsal pattern between limb insertions consisting four narrow light bands with dark edges and a transversal row of dark spots in the middle; subcaudal scales enlarged, forming broad transverse plates. Description of holotype. Adult male, medium size, snout – vent length (SVL) 74.8 mm. Head wider than body, elongate (HL 21.9 mm, HL / SVL 0.29), wide (HW 13.8 mm, HW / HL 0.63), relatively depressed (HH 7.9 mm, HH / HL 0.36, HH / HW 0.57), distinct from neck; prefrontal and postnasal regions concave; snout elongate (SE / HL 0.45), round anteriorly, longer than orbit diameter (OD / SE 0.5); scales on snout small, round to oval, granular to weakly conical, mostly homogeneous, larger than those on crown, interorbital and occipital regions; orbit of moderate size (OD / HL 0.23), pupils vertical, supraciliaries short, forming conical spines, larger anteriorly; ear opening vertically oval, small in size (ED / HL 0.09), eye to ear distance longer than orbit diameter (Eye Ear / OD 1.23); rostral much wider than deep with a medial suture, bordered by first supralabial on each side, nostrils, two supranasals and one internasal; nostrils oval, each surrounded by supranasal, rostral, first supralabial and three postnasals; two enlarged supranasals separated from one another anteriorly by one internasal; mental triangular, wider than deep; a single pair of greatly enlarged postmentals in broad contact behind mental, bordered by mental anteriorly, first infralabial laterally, and six enlarged chin scale posteriorly; supralabials 12 / 11; infralabials 10 / 10; scales of labial area decreasing in size towards jaw. Body moderately slender, relatively short (TrunkL / SVL 0.37) with the presence of non – denticulate, ventrolateral skin folds; dorsal scales granular; dorsal tubercles round, conical, present on occipital region and back, each surrounded by eight or nine granular scales, in 16 irregular longitudinal rows at midbody; ventral scales larger than dorsal scales, smooth, oval, subimbricate, largest posteriorly, largest on posterior abdomen and in precloacal region; midbody scale rows across belly between ventrolateral folds 36; gular region with homogeneous, smooth, juxtaposed granular scales; 15 or 16 poreless and pitless enlarged femoral scales each thigh, in continuous series with enlarged precloacal scales; precloacal groove absent; precloacal scales arranged in a diamond shape, precloacal pores seven, in a continuous row, pore – bearing scales enlarged; postcloacal spur each bearing three much enlarged conical scales. Fore and hind – limbs moderately slender and long (ForeaL / SVL 0.17, CrusL / SVL 0.2); tubercles on dorsum of fore and hind – limbs weakly developed; fingers and toes without distinct webbing; subdigital lamellae: finger IV 17 (with 6 basally broadened lamellae), toe IV 20 (with 7 basally broadened lamellae). Tail very long (TaL 107.2 mm, TaL / SVL 1.43); subcaudals distinctly transversely enlarged, flat, smooth. Coloration in life: ground color chocolate brown; dorsal surface of head pale brown with dark reticulated markings, distinct from the lower side by a cream line with dark edge extending from posterior of eye crossing the upper of ear to neck, another line extending from the posterior of labial crossing the ear but interrupted in the neck; eyelids yellowish cream; dorsal pattern consisting of six narrow light bands with dark edges (anterior edges darker than posterior ones) and a transversal row of dark spots in the middle: one on the tail, four between limb insertions and one anterior to the front limbs; original tail chocolate brown, scattered with small darker and cream spots, the same color with front and hind-limbs; ventral side of body cream. Coloration in preservative: In 70 % alcohol, color of this species is slightly faded. The brown turns to grey. Main morphological characters are still clearly visible. Sexual dimorphism and variation. The females differ from the males in the absence of precloacal pores and hemipenial swellings at the tail base. The number of narrow light band on the tail varies from one to two in each individual. For other morphological characteristics see Table 2. Distribution. Cyrtodactylus arnei sp. nov. is currently known only from the type locality in Hon Tre Island, Khanh Hoa Province (Fig. 1). Etymology. The new species is named after Dr. Arne Schulze, Executive Director of the Zoological Society for Conservation of Species and Populations (ZGAP) to honor his great commitment and support for herpetological research and conservation in Vietnam, in particular within the scope of the Zoo Species of the Year – The Gecko Conservation Campaign 2024. Ecological notes. The type series was found from 19: 00 to 22: 00 hrs on rock boulders and around a small cave along a rocky stream, ~ 1–2 m above the ground. This is very similar to another granite boulder species in the C. irregularis group, C. raglai (Nguyen et al. 2021 a) to which it is superficially very similar. The surrounding habitat is secondary forest composed of medium and small hardwoods mixed with shrubs (Fig. 6). Other reptile species found at the site were Calotes versicolor (Daudin), Dixonius vietnamensis Das, Gekko sp., and Eutropis multifasciatus (Kuhl). Comparisons. We compared the new species with its 30 congeners from the Cyrtodactylus irregularis group based on examination of specimens and data obtained from the literature (Smith 1921; David et al. 2004; Heidrich et al. 2007; Orlov et al. 2007; Nazarov et al. 2008, 2012; Ngo and Bauer 2008; Rösler et al. 2008; Geissler et al. 2009; Ngo and Chan 2010; Ngo 2013; Nguyen et al. 2013, 2021 a; Ziegler et al. 2013; Schneider et al. 2014; Luu et al. 2017; Pauwels et al. 2018; Neang et al. 2020; Ngo et al. 2020; Ostrowski et al. 2020, 2021; Do et al. 2021, 2023; Ngo et al. 2023, 2024). (See Table 3). Among the 30 species of the Cyrtodactylus irregularis group, Cyrtodactylus arnei sp. nov. differs: from C. arndti Ngo, Horman, Le, Pham, Phung, Do, Ostrowski, Nguyen & Zieger by having more enlarged femoral scales (12–15 vs 5–11 in C. arndti), the absence of precloacal pores in females (vs 6 in C. arndti), and the difference of dorsal color pattern (four narrow light bands with dark edges and a transversal row of dark spots in the middle vs 6 or 7 irregularly shaped bands in C. arndti); from C. badenensis Nguyen, Orlov & Darevsky by having more ventral scale rows (34 or 35 vs 25–28 in C. badenensis), the presence of enlarged femoral scales (12–15 vs absent in C. badenensis), and the presence of precloacal pores in males (5–7 vs absent in C. badenensis); from C. binhdinhensis Ngo, Do, Do, Pham, Bui, Ho, Nguyen, Ziegler & Le by having fewer ventral scale rows (34 or 35 vs 39–42 in C. binhdinhensis), more enlarged femoral scales (12–15 vs 5 or 6 in C. binhdinhensis), the absence of femoral pores in males (vs 10 in C. binhdinhensis), and the absence of precloacal pores in females (vs 5 or 6 in C. binhdinhensis); from C. bidoupimontis Nazarov, Poyarkov, Orlov, Phung, Nguyen, Hoang & Ziegler by having a longer tail (TL 93.3–107.2 mm, mean ratio TL / SVL 1.40 vs 75–86 mm, ratio TL / SVL 1.05 in C. bidoupimontis), fewer ventral scale rows (34 or 35 vs 38–43 in C. bidoupimontis), fewer dorsal tubercle rows (15–17 vs 18–24 in C. bidoupimontis), more enlarged femoral scales (12–15 vs 8–10 in C. bidoupimontis), and the presence of transversely enlarged subcaudal plates (vs absent in C. bidoupimontis); from C. buchardi David, Teynie ́ & Ohler by having a larger size (SVL 70.9–78.0 mm vs 60.0–65.0 mm in C. buchardi), more ventral scale rows (34 or 35 vs 30 in C. buchardi), the presence of enlarged femoral scales (12–15 vs absent in C. buchardi), precloacal pores in males (5–7 vs 9 in C. buchardi), more lamellae under finger IV (17–19 vs 14 in C. buchardi), more lamellae under toe IV (19–21 vs 12 in C. buchardi), and the the difference of dorsal color pattern (banded vs blotched in C. buchardi); from C. bugiamapensis Nazarov, Poyarkov, Orlov, Phung, Nguyen, Hoang & Ziegler by having a longer tail (TL 93.3–107.2 mm, mean ratio TL / SVL 1.40 vs 65.3–83.0 mm, mean ratio TL / SVL 1.08 in C. bugiamapensis), fewer ventral scale rows (34 or 35 vs 36–46 in C. bugiamapensis), fewer dorsal tubercle rows (15–17 vs 20–24 in C. bugiamapensis), more enlarged femoral scales (12–15 vs 6–10 in C. bugiamapensis), the difference of dorsal color pattern (banded vs blotched in C. bugiamapensis), and the presence of transversely enlarged subcaudal plates (vs absent in C. bugiamapensis); from C. caovansungi Orlov, Nguyen, Roman, Natalia & Nguyen by having a smaller size (70.9–78.0 mm vs 90.4–94 mm in C. caovansungi), fewer ventral scale rows (34 or 35 vs 38–44 in C. caovansungi), more enlarged femoral scales (12–15 vs 8 in C. caova