Well-preserved fin spines, ornate opercular bones and thick ctenoid scales recovered from the unconsolidated marine sediments of the Cretaceous-Tertiary boundary interval in Upper Freehold Township, New Jersey, USA derive from at least one species of enigmatic euacanthopterygian fish. Within this group the fossils are most similar to corresponding bones of some beryciforms. The fin spines are less than 1.5 cm long, have complex basal articulation structures, and a narrow posterior sulcus extending almost to the distal tip. Most spines have lateral grooves, and some have prominent anterior dentations. A few are attached to broadly keeled pterygiophores. Beryciforms and more basal clades of Acanthomorpha first appear in the Late Cretaceous. The New Jersey fossils may expand the known geographic distribution of beryciforms across the K/T boundary beyond the better known Late Cretaceous beryciforms from the Western Interior of North America, Europe, and the Middle East.