[3] The brown-banded water snake grows to a maximum total length (including tail) of 78 cm (31 inches).

The dorsal scales are strongly keeled, even on the occiput and nape, and are arranged in 19 rows.

Ventrals are 102–130 in number, the anal scale is divided, and the 61-94 subcaudals are paired and keeled.

[4] H. angulatus lives in fresh and brackish water, where it feeds on fish (such as freshwater eels) and possibly also frogs and their eggs, tadpoles, lizards, earthworms, and carrion.

[7] There is an urgent need for training of the medical team in the snake identification, clinical management of snakebite, and the existence of a human-snake conflict involving NFFC species in Bolivia.