Yellow Striped Emperor

Lethrinus ornatus, known as the Ornate emperor or Yellow-striped emperor, belongs to the family Lethrinidae and is found in the Indo-West Pacific region, particularly in tropical reef-associated waters from the Maldives and Sri Lanka to the Ryukyu Islands, Papua New Guinea, and northeast Australia.

Taxonomy

The species was first described by Achille Valenciennes in 1830 as Lethrinus ornatus Valenciennes, 1830. Its type locality is Java, Indonesia, with the name-bearing type listed as holotype RMNH D442. The scientific name means "ornate Lethrinus/emperor," where Lethrinus is derived from Greek lethrinia, a fish name associated with Pagellus, and ornatus is Latin for "ornate" or "decorated." Known taxonomic treatment includes Lethrinus insulindicus Bleeker, 1873 as a junior synonym accepted under L. ornatus, and Lethrinus xanthotaenia Bleeker, 1851 is also listed as an unaccepted synonym. The Australian Faunal Directory and WoRMS both treat Lethrinus ornatus Valenciennes, 1830 as the accepted species name. Lethrinus ornatus De Vis, 1884 is a junior homonym and is not the valid name for the species currently treated as L. ornatus Valenciennes, 1830.

Description

The species has a relatively deep and laterally compressed body, giving it a taller and heavier profile than many other emperors. It features a short, blunt snout and a convex head profile near the eye. The body coloration is dusky whitish to pale brown with 5-6 orange or golden-orange stripes along the sides. Bright red margins are present on the opercle and preopercle, making them distinctive features. The pectoral fins are orangish, while the dorsal, anal, and pelvic fins are mostly whitish to pale, often with reddish edges. Compared to other species in the genus, Lethrinus ornatus is distinguished by its deep body, short blunt snout, and convex profile around the eye. The presence of orange stripes is a strong identifying feature, as other similar emperor species may exhibit more obvious dark bands or different stripe patterns. In the field, the red opercular and preopercular margins, along with the lack of a conspicuous dark banding pattern, help differentiate it from similar species.

Distribution and habitat

The Ornate emperor is a reef-associated marine fish that occurs in shallow coastal habitats, particularly in sandy and soft-bottom areas, seagrass beds, inshore bays, lagoons, and regions near reefs. It typically inhabits a depth range of 5 to 30 meters. The geographic range of the species extends from the Maldives and Sri Lanka to the Ryukyu Islands, Papua New Guinea, and northeast Australia.

Behaviour

The species is usually found in small groups and aggregates while spawning. A reproductive study reported a spawning period for the Ornate emperor from May to November.

Diet

The Ornate emperor is a carnivorous, bottom-feeding fish that eats mainly hard-shelled invertebrates such as crustaceans, molluscs, and echinoderms. It also consumes polychaete worms and small fishes. The species feeds by crushing prey with molar-like teeth, which are well suited to breaking shells and hard exoskeletons.

Human use

The Ornate emperor has minor commercial importance in fisheries and is also taken by recreational anglers. It is caught using traps, handlines, shore seines, and trawls. The species is generally considered a food fish, although specific taste quality descriptions are lacking. The Ornate emperor is considered harmless to humans. It is listed as Least Concern (LC) on the IUCN Red List, assessed on 9 March 2015.