New provincial records of skinks (Squamata: Scincidae) from northwestern Vietnam

Abstract We report six new records of skinks from northwestern Vietnam: Eutropis macularius, Scincella devorator, S. monticola, S. ochracea, Sphenomorphus cryptotis and S. indicus. Our new findings increase the species number of skinks (Scincidae) to nine in Dien Bien Province and to 14 in Son La Province. We also provide additional natural history data of aforementioned species.

In Son La Province, previous studies documented a total of 11 species of Scincidae (Bobrov and Ho 1993, Nguyen et al. 2009. In Dien Bien Province, Do and Le (2009), Nguyen et al. (2009), andNguyen et al. (2010d) recorded six species of skinks. During recent field work in northwestern Vietnam, a number of skinks was collected from Copia, Sop Cop and Muong Nhe nature reserves. Morphological examination revealed six new records of Scincidae for Son La and Dien Bien provinces that are provided herein.

Sampling
Field surveys in northwestern Vietnam were conducted by Anh Van Pham, Tan Van Nguyen, Ngoc Thi Bich Nguyen, Men Thi Nguyen, and Hoang Van Tu (hereafter AVP et al.) between June 2013 and May 2014 and by Truong Quang Nguyen, Anh Van Pham, Hai Ngoc Ngo, Tan Van Nguyen, and Hoang Van Tu (hereafter TQN et al.) in September 2014 in the Copia and Sop Cop nature reserves (Son La Province); by Dzung Le Trung, Bach Viet Nguyen, Ngat Thi Bui, Hoa Phuong Vu (hereafter DTL et al.) between May 2012 and August 2014 in Muong Nhe Nature Reserve (Fig. 1). Specimens were collected by hand between 9:00-23:00. After taking photographs, specimens were anaesthetized in a closed vessel with a piece of cotton wool containing ethyl acetate, fixed in 80% ethanol and subsequently stored in 70% ethanol. Voucher specimens were subsequently deposited in the collections of the Tay Bac University (TBU), Son La Province and the Hanoi National University of Education (HNUE), Hanoi; and the Institute of Ecology and Biological Resources (IEBR), Hanoi, Vietnam.

Morphological characters
Measurements were taken with a digital caliper to the nearest 0.1 mm. The following abbreviations are used: SVL: Snout-vent length, TaL: Tail length, AG: Axilla-groin distance (from posterior junction of forelimb and body wall to anterior junction of hind limb and body wall with the limbs held at right angles to the body), HL: Head length (from tip of snout to posterior margin of parietal), HW: Head width (at the widest point of temporal region), SL: Snout length (from anterior corner of eye to tip of snout), SFlL: Snout-forelimb length (from tip of snout to anterior junction of forelimb and body wall, with the limb held at right angles to the body), FlL: Forelimb length (from anterior junction of forelimb and body wall to the tip of fourth finger, with the limb held at right angles to the body), HlL: Hind limb length (anterior junction of hindlimb and body wall to the tip of fourth toe, with the limb held at right angles to the body). Scalation: Paravertebral scales (number of scales in a line from posterior edge of parietals to dorsal point opposite posterior margin of the medial precloacals); ventral scale rows (number of scales from first gular to anterior margin of precloacals).
Coloration in alcohol. Dorsal surface brown, with or without small black spots; white stripe present on upper lip, extending backwards to shoulder; a dorsolateral light line extending from eye to midway on body; flank dark brown from behind the eye to hind limb, with white spots; neck and throat reddish in males and cream in females; venter and underside of tail cream. For coloration in life see Fig. 2.

Distribution
In Vietnam, this is a widespread species, known from Lang Son Province in the North to Kien Giang Province in the South. Elsewhere, E. macularius has been recorded from Pakistan, India, Bhutan, Sri Lanka, Bangladesh, Myanmar, Laos, Thailand, Cambodia, and Malaysia (Nguyen et al., 2009). This is a new record for Son La Province.

Ecology
Specimens of E. macularius were collected between 9:00 to 16:30 in the bamboo bush near the road. The surrounding habitat was disturbed secondary forest of small hardwood, bamboo and shrub.
Coloration in alcohol. Dorsum bronze brown, with two silver gray clear bands extending from parietals to base of tail and a dark wide vertebral stripe; numerous blackish spots on the labials; upper lateral zone with a distinct dark stripe from behind the eye to hind limb, with light spots; the lower edge broken in numerous small black dots; venter and under surface of tail base cream. For coloration in life see Fig. 3.

Distribution
This species is currently known only from Quang Ninh and Bac Giang provinces in northeastern Vietnam (Nguyen et al., 2009). This is the first record of Scincella devorator from northwestern Vietnam.

Ecology
The adult females were collected between 10:00 and 16:00 while crossing a forest path. The surrounding habitat was secondary forest of hardwood and shrub.
Coloration in alcohol. Dorsal surface bronze brown with some indistinct dark spots on body, dark brown laterally with a dark stripe from behind the eye to tail tip; ventral surface cream, underside of tail with some brown spots (see Fig. 4).

Distribution
This species was recently recorded in Vietnam from Cao Bang and Lang Son provinces. Elsewhere, this species is known from China (Nguyen et al. 2010 b, c). This is the first record for Dien Bien Province.

Ecology
The specimen was collected at ca. 20:00 on the ground, near a stream. The surrounding habitat was evergreen forest of hardwood and shrub.
Coloration in alcohol. Dorsum silver gray, with a dark vertebral stripe; upper lateral zone with a distinct reddish band from behind the eye to hind limb, with some light spots; the lower edge broken in somes small black dots; venter and underside of tail base cream or whitish. For coloration in life see Fig. 5.

Distribution
In Vietnam, this species has been recorded from Lai Chau Province (Eremchenko, 2003). Elsewhere, this species is known from Laos (Bourret, 1937). This is the first record of the species from Son La and Dien Bien provinces.

Ecology
Specimens were collected between 10:00 and 16:30 on the ground. The surrounding habitat was grass and shrub near a forest path.  Head longer than wide; rostral wider than high; supranasals absent; prefrontals in contact with each other; parietals in contact posteriorly; loreals 2; supraoculars 4, followed by 2 postsupraoculars, anterior one divided; primary temporal single; secondary temporals 2, upper very large and overlapped by lower one; lower eyelid scaly; supralabials 7, the fifth and sixth below the eye, separated from the eye by one row of small scales; external ear openings superficial, without lobules; mental wider than long; infralabials 6; postmental undivided; midbody scales in 34 rows; dorsal scales between lateral stripes in ½ + 6 + ½ rows, smooth; paravertebral scales 71; ventrals in 75 transverse rows, smooth; precloacals 2, enlarged; medial subcaudals widened; limbs short, pentadactyl; fingers and toes meeting when adpressed; subdigital lamellae smooth, numbering 13 under fourth finger and 20 under fourth toe.
Coloration in alcohol. Dorsum and tail base yellowish brown with a vertebral row of large black spots; numerous indistinct white spots on the labials; lateral zone with a distinct dark stripe from behind the eye to tail base, with white spots; neck and throat white, with black dots; venter and underside anterior part of tail white, posterior part of tail yellowish brown (see Fig. 6).

Distribution
This species is currently known only from northern Vietnam: Lao Cai, Bac Giang, Quang Ninh, and Nghe An provinces (Nguyen et al., 2009). This is the first record of the species from Dien Bien Province.

Ecology
The adult female was collected at ca. 9:00 on a tree branch, ca. 1.2 m above the water in a rocky stream. The surrounding habitat was evergreen secondary forest of hardwood and shrub.
Coloration in alcohol. Dorsum and tail base bronze brown; upper lateral zone with a dark gray stripe, in width of 3 or 4 scales, from behind eye to tail base; light dorsolateral stripe present on neck and shoulder, the lower margin of dark stripe with some broken light spots; lower lateral zone light gray; ventral white. For coloration in life see Fig. 7.

Distribution
In Vietnam, this species is a common species known from Lao Cai and Lang Son provinces in the North southwards to Dong Nai Province. Elsewhere, this species has been recorded from India, Bhutan, China, Taiwan, Myanmar, Laos, Thailand, Cambodia, Malaysia, and Indonesia (Nguyen et al., 2009). This is the first record of the species in Dien Bien Province.

Ecology
The specimens were collected between 9:00 and 12:00 on the ground. The surrounding habitat was secondary forest of small hardwood, bamboo and shrub.

Discussion
Except for Eutropis macularius and Sphenomorphus indicus, the remaining recorded species from Dien Bien and Son La provinces are poorly known in Vietnam due to their rarity or cryptic lifestyle in or under the leaf litter (Darevsky et al. 2004, Nguyen et al. 2010c, Nguyen et al. 2010a. Scincella devorator and Sphenomorphus cryptotis were recently described from northern Vietnam by Darevsky et al. (2004) based on a collection from Nghe An and Quang Ninh provinces. Scincella ochracea and S. monticola were recorded for the first time from the country by Eremchenko (2003) and by Nguyen et al. (2010c), respectively. Our new findings increase the total number of the family Scincidae species to nine in Dien Bien Province and 14 in Son La Province, comprising five species of Eutropis, one species of Lygosoma, two species of Plestiodon, five species of Scincella, two species of Sphenomorphus, and four species of Tropidophorus (see Table 2).  Checklist of skinks (Scincidae) recorded from Dien Bien and Son La provinces (after Bobrov and Ho 1993, Do and Le 2009, Nguyen et al. 2009, Nguyen et al. 2010a