Buccinanops monilifer, common name the collared buccinum, is a species of sea snail, a marine gastropod mollusk in the family Nassariidae, the Nassa mud snails or dog whelks.

It is, whitish, slightly diaphanous, surrounded by two brown bands, interrupted by very prominent chestnut-colored spots upon the lowest whorl of the spire.

The spire is composed of seven or eight slightly angular whorls, the two or three lowest, crowned with a row of elongated, solid, pointed tubercles, pretty near to each other.

The thin outer lip is arched, marked internally by two transverse brown bands, which are very apparent externally.

[2] This marine species occurs from Central Brazil to Argentina