Identification Characteristics:
The snout is twice as long as the eye diameter. Head scales are very small and juxtaposed. The supraocular scales are long and narrow, entire, and slightly longer than the eye length. There are 14-16 intermediate scales between the supraocular scales. The internasal scales are long, oval-shaped, and 2-2.5 times longer than adjacent scales; there are two small scales between the internasal scales. Three scales run along the midline between the internasal scales and the supraoculars. The subocular scale is long and narrow, separated from the supralabials by two rows of small scales. The temporal region has three rows of broad, smooth scales. There are nine supralabials on each side, the first supralabial is separated from the nasal scale, the second forms the anterior border of the loreal pit, and the third is the longest; there are 14-15 infralabials on each side. One pair of chin shields contacts the first and second infralabials. The body scales are in 25:25:19 rows and have prominent keels; there are 216 ventral scales; 92 paired subcaudal scales. The anal plate is entire.
The body is light brown. The dorsal surface of the head, the snout to the posterior margin of the mandible, and the ventral surface of the head are dark brown. There is a white stripe extending from the posterior of the eye to the jaw articulation, with a narrower black stripe below it. Along the midline of the back to the anterior half of the body, there are dark brown spots; these spots are staggered in the posterior half of the body. On both sides of the body, aligned with the dorsal spots, are dark brown streaks extending down to the ventral scales.
Biology and Ecology:
This venomous snake species, which poses a danger to humans, typically inhabits secondary forest habitats and streamside environments within the distribution area. Its diet consists of small carnivorous mammals and amphibians found in the distribution area. It is found at altitudes up to 1000m. It forages at night and seeks shelter in burrows, crevices, and under leaf litter during the day.
Distribution:
Vietnam: Lao Cai, Ha Giang, Cao Bang, Bac Kan, Lang Son, Thai Nguyen, Vinh Phuc, Hanoi (Ba Vi), Quang Ninh, Hai Phong, Hai Duong, Ninh Binh, Nghe An, Ha Tinh, Quang Tri, Thua Thien-Hue, Kon Tum, Gia Lai. Tri Sao, and the area around the National Park headquarters.