Scissortail Fusilier

Caesio caerulaurea, commonly known as the blue and gold fusilier, blue fusilier, gold-band fusilier, or scissor-tailed fusilier, is a marine fish species belonging to the family Caesionidae. This species is prevalent throughout the tropical waters of the Indo-Pacific region, extending to the 🌊 Red Sea.

The blue and gold fusilier was first formally described in 1801 by French naturalist Bernard Germain de Lacépède, with the type locality identified as Molucca in 🇮🇩 Indonesia. Initially referred to as Caesio caerulaureus, the name was subsequently corrected to C. caerulaurea, as the genus Caesio is classified as feminine. In 1876, Dutch ichthyologist Pieter Bleeker designated C. caerulaurea as the type species for the genus Caesio. The specific epithet caerulaurea is derived from "caeruleus," meaning sky blue, and "aureus," signifying golden, reflecting the distinctive blue back and yellow lateral stripe described by Lacépède.

Caesio caerulaurea exhibits a moderately deep, fusiform, and elongate body with moderate lateral compression. It possesses small conical teeth in the jaws, vomer, and palatine. The dorsal fin of this species is composed of 10 spines and 14-16 soft rays, while the anal fin features 3 spines and 10-12 soft rays. Scales cover both the dorsal and anal fins. This species can achieve a maximum length of 35 cm (14 inches), although more commonly reaches about 25 cm (9.8 in). The overall coloration is predominantly bluish, transitioning to white on the underside. A yellow or golden stripe runs over the lateral line and is bordered by a thin white to pale blue stripe, which extends as blackish streaks along both lobes of the forked caudal fin, giving the appearance of scissors.

The geographic distribution of Caesio caerulaurea spans the tropical waters of the Indo-Pacific, from the eastern coast of Africa and the 🌊 Red Sea to southern parts of 🇿🇦 South Africa and eastwards across the 🌊 Indian Ocean. In the 🌊 Pacific Ocean, their range extends as far east as 🇵🇫 French Polynesia, north to southern 🇯🇵 Japan, and southward to 🇻🇺 Vanuatu and 🇳🇨 New Caledonia (🇫🇷 Overseas France). In 🇦🇺 Australia, this species is found from Shark Bay in Western Australia north to Cassini Island, and from the northern Great Barrier Reef off Queensland south to Sydney. It also inhabits Christmas Island and Lord Howe Island, generally occurring at depths between 2 to 40 meters (6 ft 7 in to 131 ft 3 in) on coastal, lagoon, and seaward reefs with healthy coral growth.

Caesio caerulaurea forms large midwater schools and feeds predominantly on zooplankton. Sexual maturity is attained relatively early, with high fecundity and numerous small pelagic eggs. Spawning is a year-round activity, coinciding with lunar cycles, and involves a specific courtship pattern comprising six distinct behaviors. As dusk approaches, 1-2 males engage a female by nipping and butting her distended abdomen. This behavior ceases 60-90 minutes before spawning, after which 2-6 competing males vie for proximity to the female. The successful male and female ascend in a spiral to the surface to release eggs and milt, often succeeded by "sneaker" males that release their milt at the original spawning site. In certain instances, pairs can circumvent the approach of these sneaker males.

Caesio caerulaurea is a significant target for coastal fisheries and is commonly available in fish markets in 🇮🇩 Indonesia and the 🇵🇭 Philippines. Capture methods include drive-in nets, gill nets, fish traps, trawls, and handlines. Juvenile specimens serve as baitfish for tuna in some regions. This species is typically part of a multispecies fusilier catch, and illegal fishing practices involving explosive devices are prevalent.