Siganus stellatus

Lore & Background

Siganus stellatus was first formally described in 1775 as Scarus stellatus by the Swedish-speaking Finnish explorer and naturalist Peter Forsskål, with the type locality given as Jeddah in modern Saudi Arabia. Forsskål's description was published posthumously by Carsten Niebuhr, the only survivor of the Danish Arabia expedition, in his work Descriptiones animalium avium, amphibiorum, piscium, insectorum, vermium. The specific name stellatus means 'covered with stars,' referring to the small, closely set, dark brown to black hexagonal spots covering the body and caudal fin.

The species has two recognised subspecies according to FishBase: Siganus stellatus stellatus, found in the Red Sea, Indian Ocean, and Western Pacific Ocean; and Siganus stellatus laqueus, found in the Red Sea and Indian Ocean. Some authorities consider S. s. laqueus a separate species, Siganus laqueus, first described in 1934 by Cecil von Bonde with the type locality given as the west coast of Zanzibar. The name laqueus means 'trap' or 'snare,' referencing its frequent capture in fish traps.

The body is deep and laterally compressed, with a dorsal head profile nearly straight at a 45° angle. Juveniles have a long triangular flap on the front nostril, reduced to a low rim in adults. The caudal fin is emarginate in juveniles, becoming deeply forked with growth. The body is covered in small, closely set dark brown to black spots on a white background, creating a honeycomb pattern, with a whitish margin on the caudal fin and rear edges of dorsal and anal fins. In S. s. laqueus, the background is greyish green.

Reader's Guide

Siganus stellatus is a significant species in the Indo-Pacific region, particularly in the Red Sea and Indian Ocean, where it is caught using fish traps in Kenya and Tanzania and with spears throughout its range. Its venomous fin spines, similar in study to stonefish venom, make it notable among rabbitfishes. The species grazes on benthic macroalgae, with adults living in pairs and subadults and juveniles forming schools. Breeding shows seasonality, with peaks of juveniles appearing during summer. The taxonomic dispute over the subspecies S. s. laqueus—whether it is a separate species—reflects ongoing scientific discussion. Its honeycomb pattern and star-like spots give it a distinctive appearance, and its presence in seagrass beds, seaward reefs, and lagoons at depths up to 30 meters makes it a common sight in these habitats. Juveniles entering weedy estuarine habitats highlight its adaptability. The species' maximum total length of 40 cm and typical length of 35 cm make it a moderately sized fish in its family.

Did You Know?

• The subspecies S. s. laqueus was named for its frequent capture in fish traps; laqueus means 'trap' or 'snare'.
• The species was first described in 1775 by Peter Forsskål, with the description published posthumously by Carsten Niebuhr.
• A study of a congener found that rabbitfish venom is similar to the venom of stonefishes.