[4] The 5th edition of Fishes of the World classifies the genus Lactophrys within the family Ostraciidae in the suborder Ostracioidea within the order Tetraodontiformes.

The specific name, trigonus, means "three angles", a reference to this fish's triangular body when viewed head on.

Two areas, located on the pectoral region and halfway between gills and posterior end of carapace, contain dark-edged hexagonal plates that together form chain-like markings.

[2] The species is native to the Western Atlantic from Canada to Brazil, including the Gulf of Mexico, Bermuda and the Caribbean.

It inhabits areas with coral rubble, seagrass beds and offshore reefs, preferring depths above 50 m (160 ft).