Scincella honbaensis, Nguyen & Nguyen & Le & Nguyen & Phan & Vo & Murphy & Che, 2025

Scincella honbaensis sp. nov.

urn:lsid:zoobank.org:act:F5B84AC9-6161-4300-9136-64C13A3FC0CC

Figs 1–3 View Fig View Fig View Fig ; Table 1–3 View Table 1 View Table 2 View Table 3

Diagnosis

Scincella honbaensis sp. nov. is distinguished from all of its congeners by a combination of the following morphological characters: relatively small size in adults (SVL 47.4 mm); 28 smooth midbody scale rows; dorsal scales enlarged, 6 rows on back; 64 paravertebrals; 74 ventral scale rows; 4 supraoculars; prefrontals in broad contact with one another; 2 loreals; 7 supralabials, fifth and sixth below the eye; 1 anterior and 2 posterior enlarged temporals; 3 pairs of nuchals; tympanum deeply sunk and oval; 15 or 16 smooth lamellae beneath finger IV and 21 beneath toe IV; 2 enlarged precloacals; dorsum with 2 rows of longitudinal black dots.

Etymology

The specific epithet ‘ honbaensis ’ is a toponym derived from the Hon Ba Mountain where the new species was discovered. We recommend ‘Hon Ba Ground Skink’, ‘Thằn lằn cổ hòn bà’, and ‘Rắn mối hòn bà’ as the common English, Vietnamese, and local names of the new species, respectively.

Type material

Holotype VIETNAM • ♂, adult; Khanh Hoa Province, Hon Ba Mountain ; 12°06′59.7″ N, 108°56′44.0″ E; 1510 m a.s.l.; 23 Jun. 2017; Luan T. Nguyen and Manh V. Le leg.; GenBank: PV022547 ; ITBCZ 4679 ; ITBCZ. GoogleMaps

Description (holotype, ♂, adult)

MEASUREMENTS. SVL 47.4 mm; snout relatively long and pointed (SnL = 4.1 mm; SnL/HW = 0.66; SnL/ HL = 0.34); lower eyelid with an undivided transparent disc; body rather compressed and slender; tail longer than snout–vent length, regenerated on tip part; limbs pentadactyl, toes reach to wrist when limbs adpressed ( Fig. 3 View Fig ).

Head scales smooth; rostral convex, distinctly visible from above, in broad contact with frontonasal; no supranasals; prefrontals in broad contact with one another; four supraoculars; frontal narrowing posteriorly, longer than wide (3.0 mm vs 1.6 mm), longer than its distance from snout (2.5 mm), bordered laterally by first two supraoculars, anteriorly by prefrontals, and posteriorly by frontoparietals; pair of frontoparietals, shorter than frontal, in contact with supraoculars 2–4; parietals in contact posteriorly, behind interparietal; 3 pairs of nuchals, twice the size of dorsal scale; 7 supralabials on both sides, fifth and sixth below eye, sixth largest; 2 loreals, equal in size; 2 preoculars, lower one much larger than upper one; nostril in center of nasal, which in contact with first supralabial, rostral, anterior loreal, and frontonasal; 8 supraciliaries, first largest; 1 enlarged anterior temporal, in contact with sixth and seventh supralabials; 2 posterior temporals, lower one much smaller and overlapping upper one; 7 infralabials, first two in contact with postmental, second and third in contact with fist chin shield; 3 pairs of enlarged chin shields, first pair medially in contact with each other, second pair separated by small scale; tympanum deeply sunk, oval, and oblique.

Dorsal scales smooth, larger than lateral and ventral scales, 6 rows on back between dorsolateral bands; 28 midbody scale rows; 64 paravertebral scales; ventral scales smooth, in 73 rows; subcaudal scales on original part of tail slightly enlarged; 15 or 16 smooth lamellae beneath finger IV and 21 beneath toe IV; 2 enlarged precloacal scales, right scale overlapping left one.

In life, overall dorsal coloration olive with two longitudinal black dots on dorsum; dorsolateral band dark brown and continuous; a black band on side of snout, continuous behind eye and joining dorsolateral band; lower half of flank light brown with sparse black dots; lower part of head and neck somewhat bluish white; lower part of neck, body, limbs, and tail yellowish to yellow; free margin of upper and lower eyelids orange to yellow; eye immaculate black. In preservation, color fades but pattern remained with two longitudinal black dots on dorsum and sparse black dots on lower part of side; overall dorsal and lateral coloration light brown; venter cream. Morphological characters of the holotype were summarized in Table 3 View Table 3 .

Field notes

The specimen was collected at night, on the ground near the Forest Station on top of Hon Ba Mountain. It was seen when removing tile debris. Surrounding habitat consisted of montane primary evergreen forest with scattered rocks and thick layer of leaf litter.

Distribution

The new species is currently known only from Hon Ba Mountain, Khanh Hoa Province, Vietnam ( Fig. 1 View Fig ).

Comparisons

Scincella honbaensis sp. nov. differs morphologically from its congeners in Indochina and China as follows: from S. apraefrontalis by having more midbody scale rows (28 vs 18), more lamellae beneath toe IV (21 vs 8–9), more paravertebral scale rows (64 vs 52), first supralabial and nasal separated (vs fused), and presence (vs absence) of prefrontal ( Nguyen et al. 2010b); from S. badenensis by having fewer midbody scale rows (28 vs 32–36), more nuchal pairs (3 vs 0–1), one (vs two) first enlarged temporal, and fewer longitudinal dorsal scale rows on back (6 vs 8) ( Nguyen et al. 2019); from S. baraensis by having fewer midbody scale rows (28 vs 30), more ventrals (74 vs 64–66), absence (vs presence) of weak auricular lobules, and fewer longitudinal dorsal scale rows on back (6 vs 8) ( Nguyen et al. 2020); from S. barbouri ( Stejneger, 1925) by having more lamellae beneath toe IV (21 vs 15–17), more lamellae beneath finger IV (15 or 16 vs 9–10), fewer nuchal pairs (3 vs 4 or 5), fewer paravertebral scale rows (64 vs 70–79), ( Stejneger 1925; Ouboter 1986); from S. darevskii by having more lamellae beneath toe IV (21 vs 17), more lamellae beneath finger IV (15 or 16 vs 12), more ventrals (74 vs 65), prefrontals in contact (vs separated), fewer supraoculars (4 vs 5), and absence (vs presence) of weak auricular lobules ( Nguyen et al. 2010c); from S. devorator by having more lamellae beneath toe IV (21 vs 17 or 19), prefrontals in contact (vs separated), limbs in touch (vs separated) when adpressed, and absence (vs presence) of a black broad vertebral band ( Darevsky et al. 2004; Nguyen et al. 2011); from S. doriae by having more lamellae beneath toe IV (21 vs 15–18), head relatively longer and pointed (HW/HL = 0.52 vs 0.64), frontal longer (vs as long as) its distance from snout, dorsum with two longitudinal rows of black spots (vs scattered black spots) ( Boulenger 1887; Smith 1935; Taylor 1963; Bourret 2009); from S. fansipanensis by having more midbody scale rows (28 vs 22), more lamellae beneath toe IV (21 vs 10–12), more lamellae beneath finger IV (15 or 16 vs 7–9), and limbs in touch (vs separated) when adpressed (Okabe et al. 2004); from S. huanrenensis Zhao & Huang, 1982 by having lamellae beneath toe IV (21 vs 13–16), more lamellae beneath finger IV (15 or 16 vs 9), fewer paravertebral scale rows (61 [not included nuchals] vs 66–84), and limbs in touch (vs separated) when adpressed ( Zhao & Huang 1982; Chen et al. 2001); from S. melanosticta by having more nuchal scales (3 pairs vs 0), fewer midbody scale rows (28 vs 34–38), dorsal scale enlarged (vs same size as lateral scales), and fewer longitudinal dorsal scale rows on back (6 vs 10) ( Smith 1935; Taylor 1963; Bourret 2009; Neang et al. 2018); from S. modesta Günther, 1864 by having more lamellae beneath toe IV (21 vs 10–17), more lamellae beneath finger IV (15 or 16 vs 8–12), and dorsum with two longitudinal rows of black spots (vs scattered black spots) ( Smith 1935; Chen et al. 2001); from S. monticola by having more midbody scale rows (28 vs 22–26), more lamellae beneath toe IV (21 vs 10–13), more paravertebrals (64 vs 52–59), more ventrals (74 vs 52–58), and prefrontals in contact (vs separated) ( Schmidt 1927; Neang et al. 2018); from S. nigrofasciata by having fewer midbody scale rows (28 vs 32–33), more nuchal scales (3 pairs vs 0 or 1), more lamellae beneath toe IV (21 vs 15–17), fewer paravertebral scale rows (64 vs 69–74), fewer longitudinal dorsal scale rows on back (6 vs 8), and fewer enlarged anterior temporal (1 vs 2) (Neang et al. 2018); from S. ochracea by having fewer midbody scale rows (28 vs 30–32), more lamellae beneath toe IV (21 vs 16–18), more ventrals (74 vs 66–71), fewer enlarged anterior temporal (1 vs 2), absence (vs presence) of weak auricular lobules, and absence (vs presence) of dark vertebral stripe ( Bourret 2009; Pham et al. 2015; Neang et al. 2018); from S. ouboteri by having fewer midbody scale rows (28 vs 30–32), more ventrals (74 vs 65–71), fewer enlarged anterior temporals (1 vs 2), more lamellae beneath finger IV (15 or 16 vs 10–12), and absence (vs presence) of weak auricular lobules ( Pham et al. 2024); from S. potanini Günther, 1896 by having more lamellae beneath finger IV (15–16 vs 9.9 ±0.7), more lamellae beneath toe IV (21 vs 14.3 ± 1.5–17), and limbs in touch (vs separated) when adpressed ( Günther 1896; Ouboter 1986); from S. przewalskii ( Bedriaga, 1912) by having fewer midbody scale rows (28 vs 32–34), more lamellae beneath toe IV (21 vs 17), more supralabials (7 vs 6), and more infralabials (7 vs 6) ( Wang & Zhao 1986); from S. punctatolineata Boulenger, 1893 by having more midbody scale rows (28 vs 24–26), more lamellae beneath toe IV (21 vs 12–14), prefrontals in contact (vs separated), presence (vs absence) of nuchals, and limbs in touch (vs separated) when adpressed ( Smith 1935); from S. rara by having more midbody scale rows (28 vs 24), more paravertebrals (64 vs 53), and a single (vs double) row of lamellae beneath toes and fingers II–IV ( Darevsky & Orlov 1997); from S. reevesii by having more nuchals (3 pairs vs 0 or 1), dorsal scale enlarged (vs same size as lateral scales), fewer enlarged anterior temporal (1 vs 2), and fewer longitudinal dorsal scale rows on back (6 vs 8) ( Smith 1935; Bourret 2009; Neang et al. 2018); from S. rufocaudata by having fewer midbody scale rows (28 vs 32–34), more lamellae beneath toe IV (21 vs 15–17), fewer paravertebrals (64 vs 68), fewer longitudinal dorsal scale rows on back (6 vs 10), and one (vs two) anterior temporal ( Darevsky & Nguyen 1983; Neang et al. 2018); from S. rupicola by having fewer midbody scale rows (28 vs 34–36), more nuchals (3 pairs vs 0 or 1), fewer paravertebrals (64 vs 68–73), fewer longitudinal dorsal scale rows on back (6 vs 8), and one (vs two) anterior temporal ( Smith 1935; Taylor 1963; Neang et al. 2018); from S. schmidti Barbour, 1927 by having more midbody scale rows (28 vs 26), more lamellae beneath toe IV (21 vs 11), and limbs in touch (vs separated) when adpressed ( Barbour 1927); from S. truongi by having more ventrals (74 vs 60–70), more lamellae beneath toe IV (21 vs 13–15), and more lamellae beneath finger IV (15 or 16 vs 10) ( Pham et al. 2025); from S. tsinlingensis Hu & Zhao, 1966 by having more lamellae beneath toe IV (21 vs 11–16) and fewer paravertebrals (64 vs 78–85), ( Ouboter 1986; Inger et al. 1990); from S. victoriana Shreve, 1940 by having more midbody scale rows (28 vs 26), more lamellae beneath toe IV (21 vs 15 or 16), more paravertebrals (64 vs 50–57), more ventrals (74 vs 53–56), and smooth (vs keeled) scales on dorsum and tail ( Ouboter 1986; Neang et al. 2018); and from S. wangyuezhaoi Jie, Gao, Huang, Ren, Jiang, Li & Li, 2023 by having more lamellae beneath toe IV (21 vs 13–16), more lamellae beneath finger IV (15 or 16 vs 9–11), and more supraciliaries (8 vs 5–7) ( Jia et al. 2023).