Dwarf water cobra

Naja nana is classified under the genus Naja of the family Elapidae, and considered a member of the Boulengerina subgenus, along with related species such as Naja annulata, Naja christyi, and Naja melanoleuca. The genus name Naja is a Latinisation of the Sanskrit word nāgá (नाग), meaning "cobra”; the species name nana derives from the Latin word, nanus, which means dwarf, in reference to its small size.

The dwarf water cobra typically doesn't grow longer than 1 m (3.3 ft),^[2] unlike the two other semiaquatic African Naja species, Naja annulata and Naja christyi, both of which can attain lengths of up to about 2.5 m (8.2 ft).^[3]

Distinguishing features of the species include its characteristic defensive posture, its aquatic lifestyle, the straight-row arrangement of its dorsal scales, and its distinctive coloration: black with small white or yellowish spots, a whitish abdomen, and a black underside of the tail.^[1]

The eggs of the dwarf water cobra are large and elongated, and require 70 days of incubation to hatch.^[4]

Dwarf water cobras can swim and climb, but generally prefer a terrestrial habitat, although they will hunt and defecate in water when able.^[5] In the wild they are exclusively piscivorous,^[6][3] although in captivity they are often fed a rodent-based diet.^[5] One case of cannibalism of a conspecific snake is known.^[3]