Pareques acuminatus was first formally described in 1801, based on Albertus Seba's 1759 Chaetodon, lineis fuscis, longitudinalibus, varius, by the German naturalists Marcus Elieser Bloch and Johann Gottlob Theaenus Schneider without a type locality being given.

[7] The specific name of the species, acuminatus, means "acute" or "pointed", an allusion to the shape of the spiny dorsal fin.

The villiform teeth are arranged in bands with those in the outer row of the lower jaw being enlarged.

[2] P. acuminatus is found in the western Atlantic Ocean where it occurs from North Carolina southwards through the Caribbean and Gulf of Mexico to Venezuela.

[3] It is found at depths between 60 and 70 metres (200 and 230 feet) in clear waters around tropical islands, often associated with coral reefs, as well as in nearby bays where there is a rubble substrate or the eroded borders of beds of seagrass.