Morphologically it looks very close to Lesser Black Krait (Bungarus lividus). Both species are known for patternless uniform black body with yellowish underside. Apart from scale counts, both species can be differentiated by checking vertebral scale shape and size. In B. niger they are significantly larger than adjacent scales and of hexagonal shape. While Lesser Black Krait they are not much distinct than adjacent scales and significantly narrower than most of the Krait species.
Average length- 90cm.
Maximum length- 130cm.
Body slender with shiny smooth scales, top scales hexagonal and larger like other Kraits. Body color jet black or black mixed with red, brown or blue without any band or marking.
Belly color milky white or yellowish-white. Edge of ventral scales with reddish or brownish tint which extends up to few rows of side dorsal scales. Subcaudal scales undivided.
Head depressed with a rounded snout, slightly broader than neck. Upper lip color yellowish-brown. Moderate eyes blackish on upper. Nasal pit color pink; Moderate eyes looks entirely black in live state with rounded pupil.
Shorter than typical range and ends with a pointed tip.
The venom of B. niger causes progressive paralysis of the peripheral nervous system, leading to respiratory paralysis and death due to asphyxia, and it causes systemic muscle damage with myoglobinuria, acute renal failure and hyperkalaemia. Thus, the complications of both neurotoxic and myotoxic envenoming must be anticipated in patients bitten by such a snake. Assisted ventilation is crucial and dialysis may be needed, too.