This crown distinguishes it from the closely related and similar-looking Bermuda blue angelfish (Holacanthus bermudensis), with which it overlaps in range and can interbreed.

In 2010, the queen angelfish was assessed as least concern by the International Union for Conservation of Nature as the wild population appeared to be stable.

The queen angelfish was first described as Chaetodon ciliaris in 1758 by Carl Linnaeus in the 10th edition of his Systema Naturae, with the type locality given as the "Western Atlantic/Caribbean".

[3] In 1802 it was moved by French naturalist Bernard Germain de Lacépède to the genus Holacanthus,[4] the name of which is derived from the Ancient Greek words "holos" (full) and "akantha" (thorn).

[2] Its specific name ciliaris means "fringed", a reference to its squamis ciliatis ("ciliate scales").

[6] Marine angelfish of the genus Holacanthus likely emerged between 10.2 and 7.6 million years ago (mya).

The most basal species is the Guinean angelfish (Holacanthus africanus) off the coast of West Africa, indicating that the lineage colonized the Atlantic from the Indian Ocean.

[7] The closure of the Isthmus of Panama 3.5–3.1 mya led to the splitting off of the Tropical Eastern Pacific species.

[14][15] The species is covered in yellow-tipped blue-green scales, with a bright yellow tail, pectoral and pelvic fins.

[18] Queen angelfish are found in tropical and subtropical areas of the Western Atlantic Ocean around the coasts and islands of the Americas.

[1][6] Queen angelfish are benthic or bottom-dwelling and occur from shallow waters close to shore down to 70 m (230 ft).

Queen angelfish appear to be selective feeders as the proportion of prey in their diet does not correlate with their abundance.

[15] Courtship involves the male showing his side to the female and flicking his pectoral fins at her or "soaring" above them.

Juvenile angelfish live alone and in territories encompassing finger sponges and coral, where they establish cleaning stations for other fish.

[21] As juveniles, angelfish can adapt to eating typical aquarium food and hence have a higher survival rate than individuals taken as adults, which require a more specialized diet.

[23] In 2010, the queen angelfish was assessed as least concern by the International Union for Conservation of Nature, as the species is only significantly fished off Brazil and the wild population appeared to be secure.