The Asian elapid genus Bungarus are commonly called kraits. They are terrestrial in forests and some agricultural habitats. They feed on other snakes but will take other small vertebrates. Their bodies are dorsolaterally compressed, which makes a cross-section of their body triangular. Their venom is highly neurotoxic, and they are responsible for human bites in many South and southeastern Asian countries. Many species exceed a meter in length, and some reach two meters.
Aksornneam et al. (2024) described a new species of Bungarus from the Tenasserim Mountain Range in Ratchaburi Province, western Thailand. The new species, Bungarus sagittatus, can be distinguished from all other kraits by having the combination of 15 dorsal scale rows, 215– 217 ventral scales, 48–56 undivided subcaudal, prefrontal suture 2.4–2.6 times length of internasal suture; anterior chin shields larger than posterior chin shields; head of adult uniform black while juvenile black with small dim white patches on temporal and parietal areas; dorsal body black, with 25–31 white narrow bands, white and black bands at midbody covering 1.5–3.0 and 4.5–6.0 vertebral scales, respectively; dorsal body black bands not intruding ventrals or intruding ventrals less than 0.5 times of the width of outer dorsal scales; ventral surface of body immaculate white; ventral side of tail white with a row of dark brown triangular patches on middle pointing posteriorly; tail relatively long, tail length/total length 0.140–0.143. Genetically, the new species has uncorrected pairwise divergences of ≥ 8.29% of the mitochondrial cytochrome b from other Bungarus species. Currently, the new species is only known from the type locality.
Bungarus sagittatus is known only from the locality of Khao Krachom, Suan Phueng District, Ratchaburi Province. The area is part of the Tenasserim Mountain Range, which lies on the Thai-Myanmar border. Most observations of Bungarus sagittatus occurred at night; three specimens were collected in a hill evergreen forest (834 m to 987 m elevation) between 2050 and 2210 h with air temperature of 24.1 °C and relative humidity of 91.7%. One juvenile (ZMKU R 01090) was collected in a pitfall trap in the mixed deciduous forest (at 619 m ASL) during the day. One subadult (not collected) was found swallowing an adult scincid lizard, Scincella reevesii, on the forest floor in a hill evergreen forest (1,049 m ASL) on 6 November 2022 at 2154 h. The new species was found sympatrically with other snake species such as Ahaetulla prasina, Boiga cyanea, Coelognathus flavolineatus, Gonyosoma oxycephalum, Lycodon ophiophagus, Ptyas carinata Rhabdophis chrysargos, Psammodynastes pulverulentus, Pareas carinatus, Argyrophis diardii, Naja kaouthia, Bungarus flaviceps, Ophiophagus hannah and Trimeresurus cf. popeiorum.
Citation
Aksornneam A, Rujirawan A, Yodthong S, Sung YH, Aowphol A. 2024. A new species of krait of the genus Bungarus (Squamata, Elapidae) from Ratchaburi Province, western Thailand. Zoosystematics and Evolution 100(1):141-54.
