Lygosoma veunsaiensis, Geissler, Peter, Hartmann, Timo & Neang, Thy, 2012

Geissler, Peter, Hartmann, Timo & Neang, Thy, 2012, A new species of the genus Lygosoma Hardwicke & Gray, 1827 (Squamata: Scincidae) from northeastern Cambodia, with an updated identification key to the genus Lygosoma in mainland Southeast Asia, Zootaxa 3190, pp. 56-68: 58-63

publication ID

http://doi.org/ 10.5281/zenodo.280057

persistent identifier

http://treatment.plazi.org/id/03FC3941-4F01-FF81-FF55-FD9911F37CD1

treatment provided by

Plazi

scientific name

Lygosoma veunsaiensis
status

sp. nov.

Lygosoma veunsaiensis   sp. nov.

Figures 2–5 View FIGURE 2 View FIGURE 3 View FIGURE 4 View FIGURE 5 .

Holotype. CBC 0 0 808, adult male, collected by Gabor Csorba on 24 February 2010 at O'Kasieb campsite at 14 °01’00.2’’N, 106 ° 45 ’09.0’’E, 114 m in disturbed semi-deciduous forest in Seun Sai District, Ratanakiri Province, Cambodia.

Diagnosis. Lygosoma veunsaiensis   sp. nov. is differentiated from all other congeners by the following combination of characters: (1) body elongated, SVL approximately 5.4 times of HlL; (2) supranasals distinct, separated from each other by frontonasal; (3) frontoparietals paired; (4) supraciliaries nine; (5) supralabials five; (6) lower eyelid scaly; (7) infralabials five; (8) external ear openings absent; (9) midbody scale rows 22; (10) paravertebral scales 51; (11) ventrals in 49 transverse rows; (12) subdigital lamellae on fourth finger five; (13) subdigital lamellae on fourth toe nine; (14) a light stripe present on outer edge of the dorsum; and a dark dorsolateral stripe present, from behind the eye to the tail.

Etymology. We name this new species after the type locality to underscore the importance of Veun Sai Proposed Protected Forest for the conservation of Cambodia’s threatened biodiversity.

Description of holotype. Male specimen; SVL 33.6 mm, tail tip lost, for further measurements see Table 1. Head distinct from neck; snout rounded; rostral almost three times wider than long, forming a transverse narrow suture with frontonasal, separated from supranasals; frontonasal 1.3 times as wide as long; prefrontals small, widely separated from each other by frontal, touching loreal as well as anterior preoculars laterally; frontal large, elongate, diamond shaped, widened anteriorly and sharpened posterioly, longer than its distance to the tip of the snout, in contact with frontonasal, prefrontals, first supraciliary, first and second supraoculars; frontoparietals paired, in broad contact medially at anterior half and widely separated posteriorly, bordered by frontal anteriorly, second, third and fourth supraoculars laterally, interparietal, and parietals posteriorly; interparietal diamond shaped, widened anteriorly and sharpened posteriorly, bearing an eye spot; parietals subrectangular, in contact posteriorly, bordered by seven dorsal scales posteriorly and two small temporals laterally, enlarged nuchals absent; three temporals, anterior one smaller. Nostril within nasal; nasal in contact with rostral, supranasal, frontonasal, first supralabial and anterior loreal; two small loreals on the right side, similar in size, vertically elongated, bordered by first and second supralabials, nasal, frontonasal, prefrontals, and anterior preoculars; one large loreal on the left side, subtriangular in shape; two small subrectangular preoculars bordered by smaller presuboculars, forming a transition to the lower eyelid; four supraoculars; nine supraciliaries; lower eyelid scaly; two enlarged postoculars, the lower one bordering the fifth supralabial; five supralabials, the fifth largest; external ear openings absent, covered by scales at small depressed cavity behind mandible. Mental wider than long, in contact with the postmental and first infralabials; postmental single, bordering mental, first infralabials and first pair of chin shields; first pair of chin shields in broad contact medially; second pair of chin shields separated from each other by a small gular scale, in contact with first pair of chin shields anteriorly, second, third and fourth infralabials laterally and three gular scales posteriorly; five infralabials (Figs. 2,3); body elongated, the distance between axilla and groin almost five times the length of the forelimb; 22 midbody scale rows; 51 paravertebral scales; dorsal and ventral scales smooth, enlarged, similar in size; ventrals in 49 transverse rows; scales on flanks and throat smaller than those on body and venter; three enlarged precloacals, the medial largest, the outer scales overlap the inner; 63 undivided subcaudal scales, anterior four paired, followed by 59 undivided scales (incomplete as the tail tip is missing); forelimb and hind limb short, pentadactyl; fingers and toes widely separated when adpressed; the first finger and toe less than one-half the second; five smooth subdigital lamellae on fourth finger; nine smooth lamellae on fourth toe. Selected scalation traits across all Southeast Asian taxa are given in Table 1.

Coloration in preservative. Upper surface of head and body brownish with dark brown mottling, darker brown and lighter irregular spotted pattern on tail; flanks lighter; supraocular darker; small dark eye spot present on posterior interparietal; two dorsolateral light beige stripes, bordered dorsally by a thin dark line, starting on neck and running down each side of the back, becoming less distinct behind the shoulder ( Fig. 2 View FIGURE 2 b). Neck and back between these two stripes stained with dark brown. Lateral stripe (dark brown), bordering the light beige dorsolateral stripes ventrally, starting at the hind margin of nasal, running down on head and flanks reaching the tail ( Figs. 3 View FIGURE 3 , 4 View FIGURE 4 ). Beige coloration below the lateral stripe, with a pale series of brown spots forming a lateral line on the flank. Lateral side of tail beige, stained with tiny dark grey spots. Ventral surface whitish beige, immaculate.

Coloration in life. Reddish brown ground color on head and body, becoming greyish on the upper tail surface ( Fig. 5 View FIGURE 5 ). Color pattern the same as in preservative.

Distribution. The scincid Lygosoma veunsaiensis   sp. nov is currently known only from the type locality in the Proposed Protected Forest in Veun Sai District, Ratanakiri Province, northeastern Cambodia ( Fig. 1 View FIGURE 1 ).

Natural history. The specimen was found on the ground, near a 3 m wide slow moving section of the O'Kasieb stream during the day in the dry season in disturbed semi-deciduous evergreen forest.

Comparisons. The new species is distinguishable from all other species of the genus Lygosoma Hardwicke & Gray, 1827   known to occur in mainland Southeast Asia ( Smith 1935, Smith 1937 a, Shreve 1940 Taylor 1963, Bourret 2009, Nguyen et al. 2009, Das 2010, Geissler et al. 2011) by a combination of scalation and coloration features. Lygosoma veunsaiensis   sp. nov. differs: from L. albopunctata ( Gray, 1846)   by having medially separated supranasals instead of supranasals being in contact medially, having five supralabials instead of seven, lacking external ear openings instead of having oval ear openings, having 22 midbody scale rows instead of 26–28, and having 51 paravertebral scales instead of 63–72 ( Boulenger 1887, Smith 1935); from L. angeli (Smith, 1937)   it differs by having medially separated supranasals instead of supranasals being in contact medially, lacking external ear openings instead of having small ear openings, having five supralabials instead of seven, having 22 midbody scale rows instead of 30, and having fewer paravertebral scales (51 vs. 107–115) ( Smith 1937 b, Geissler et al. 2011); from L. anguinum ( Theobald, 1868)   it differs by having medially separated supranasals instead of supranasals being in contact medially, lacking external ear openings instead of having small rounded ear openings, having five supralabials instead of seven, having scaly lower eyelids instead of eyelids bearing transparent discs, and by the presence of dark dorsolateral stripes instead of having a uniform olive-brown back ( Theobald 1868, Boulenger 1887); from L. bampfyldei ( Bartlett, 1895)   it differs by having medially separated supranasals instead of supranasals being in contact medially, lacking external ear openings instead of having small ear openings with three projecting lobules, lacking a deep groove from below the eye to nostril, having five supralabials instead of six, having 22 midbody scale rows instead of 38–40, having nine subdigital lamellae on fourth toe instead of 14 ( Bartlett 1895, Grismer 2011); from L. boehmei Ziegler, Schmitz, Heidrich, Vu & Nguyen, 2007   it differs by having medially separated supranasals instead of supranasals being in contact medially, lacking external ear openings instead of having small ovoid ear openings, having five supralabials instead of seven, having 22 midbody scale rows instead of 32, having 51 paravertebral scales instead of 66, and having nine subdigital lamellae on fourth toe instead of 14 ( Ziegler et al. 2007); from L. bowringii ( Günther, 1864)   it differs by having medially separated supranasals instead of supranasals being in contact medially, lacking external ear openings instead of having small rounded ear openings, having five supralabials instead of seven supralabials, having 22 midbody scale rows instead of 28, having nine subdigital lamellae on fourth toe instead of 12 or 13, and lacking black and white spotted flanks ( Günther 1864, Smith 1935, Taylor 1963, Geissler et al. 2011); from L. corpulentum ( Smith, 1921)   it differs by having medially separated supranasals instead of supranasals being in contact medially, lacking external ear openings instead of having subcircular ear openings, having five supralabials instead of seven, having 22 midbody scale rows instead of 36–40, having 51 paravertebral scales instead of 78–86, and bearing dorsolateral stripes instead of having a uniformly brown back ( Smith 1921, Geissler et al. 2011); from L. frontoparietale ( Taylor, 1962)   it differs by having medially separated supranasals instead of supranasals being in contact medially, lacking external ear openings instead of having small ear openings, having five supra- and infralabials instead of seven supralabials and six infralabials, having 22 midbody scale rows instead of 28–30, and by having nine subdigital lamellae on fourth toe instead of 13 ( Taylor 1962, 1963); from L. haroldyoungi ( Taylor, 1962)   it differs by having medially separated supranasals instead of supranasals being in contact medially, lacking external ear openings instead of having ear openings, having five supra- and infralabials instead of nine supra- and infralabials, having 22 midbody scale rows instead of 38–42, having 51 paravertebral scales instead of 141–145, having nine subdigital lamellae on fourth toe instead of six or seven, and by bearing dorsolateral stripes instead of 22–32 transverse dark bands ( Taylor 1962, 1963); from L. herberti ( Smith, 1916)   it differes by having medially separated supranasals instead of supranasals being in contact medially, by having five supra- and infralabials instead of seven supralabials and six infralabials, by having 22 midbody scale rows instead of 26–30, having smooth instead of carinated body scales, and having nine subdigital lamellae on fourth toe instead of 15 ( Taylor 1963); from L. isodactylum ( Günther, 1864)   it differs by having medially separated supranasals instead of supranasals being in contact medially, nasals not being fused with supranasals instead of being fused anteriorly, having five supralabials instead of seven, having 22 midbody scale rows instead of 30–34, having 51 paravertebral scales instead of 88–98, and lacking a transverse dark band between the ears ( Günther 1864, Taylor 1963); from L. koratense ( Smith, 1917)   it differs by having medially separated supranasals instead of supranasals being in contact medially, lacking external ear openings instead of having ear openings, five supralabials instead of eight, having 22 midbody scale rows instead of 32–34, having nine subdigital lamellae on fourth toe instead of 13 or 14, and the absence of a dark blotch on the base of each dorsal and lateral body scale ( Smith 1935, Taylor 1963); from L. lineolatum ( Stolicka, 1870)   it differs by having medially separated supranasals instead of supranasals being in contact medially, having two frontoparietals instead of one, having five supralabials instead of seven, lacking external ear openings instead of having moderately rounded ear openings, having five subdigital lamellae on fourth finger instead of 12, and lacking light longitudinal lines along the back and flanks ( Smith 1935); from L. popae Shreve, 1940   it differs by having medially separated supranasals instead of supranasals being in contact medially, lacking external ear openings instead of having minute subcircular ear openings, by having 22 instead of 24 scale rows around midbody, having 51 instead of 92–95 paravertebral scales, and having a scaly lower eyelid instead of an eyelid bearing a transparent disc ( Shreve 1940); from L. punctata ( Linnaeus, 1758)   it differs by having medially separated supranasals instead of supranasals being in contact medially, the absence of an undivided transparent disc in the lower eyelid, lacking external ear openings instead of having small oval ear openings, having 22 midbody scale rows instead of 24–28, having nine subdigital lamellae on fourth toe instead of 11–14 ( Smith 1935, Bourret 2009); and from L. quadrupes ( Linnaeus, 1766)   it difers by having distinct nasals and supranasals instead of nasals being fused with supranasals, having two frontoparietals instead of a single one, having five supra- and infralabials instead of six or seven, lacking external ear openings instead of having small punctiform ear openings, having 22 midbody scale rows instead of 24–28, having 51 paravertebral scales instead of 109–116, and having two broad dark dorsolateral stripes along flanks and tail ( Linnaeus 1766, Smith 1935, Taylor 1963, Bourret 2009, Geissler et al. 2011).

Kingdom

Animalia

Phylum

Chordata

Class

Reptilia

Order

Squamata

Family

Scincidae

Genus

Lygosoma