What is the most definitive physical feature defining the dorsal side of an adult common krait?

Answer

Glossy black or bluish-black hue with narrow, white crossbands

The most definitive feature is its coloration: a glossy black or bluish-black back overlaid with distinct, narrow, white or pale yellowish crossbands.

What is the most definitive physical feature defining the dorsal side of an adult common krait?
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