Order : Perciformes
Family : SIGANIDAE
Species : 29 species in 1 genus (as of 2024)
Maximum Length : at least 42 cm (e.g. Siganus guttatus).

Siganidae is a small family comprising 29 species of 'rabbitfish' in the sole genus Siganus. Rabbitfishes are so-called because their snouts resemble the noses of rabbits. They are also known as 'spinefoots' probably due to the presence of numerous spines on a number of fins which can give a painful sting.

Rabbitfishes occur in a range of habitats including shallow coral reefs, rocky areas, and beneath man-made structures such as jetties, boardwalks and pontoons. Some species are boldly patterned and others are heavily spotted.

Most species appear to be exclusively herbivorous, feeding mainly on algae, but recent studies have documented Siganus rivulatus (Marbled Rabbitfish) feeding on soft, gelatinous parts of live jellyfishes and comb jellies (Bos et al, 2016).

Bos & Fransen (2018) observed Siganus canaliculatus (White-spotted Rabbitfish) visiting 'cleaning stations' by day to have external parasites removed by shrimps or cleaner fishes.

Another study of Siganus canaliculatus in Palau documented large groups of this species coming together four or five days after the new moon to spawn: on average nearly 300,000 eggs were released by females (Hasse et al, 1997). The same authors documented marked darkening of Siganus canaliculatus when fish were stressed. When disturbed in shallow water, they may lie on their sides, and flatten themselves on the substrate while swimming slowly away.

Native populations of Siganus occur in the Indian Ocean, Southeast Asia and the Pacific Ocean.

Figs 1 and 2 : Dorso-lateral view (oblique-angle view) of a pair of Orange-spotted Rabbitfish (Siganus guttatus) beneath a jetty at Sentosa Island, Singapore. According to Fishbase this species may grow up to 42 cm, but typically reaches 25 cm.

Figs 3 and 4 : Side view and top view of a White-spotted Rabbitfish (Siganus canaliculatus) at Changi Beach, Singapore. According to Fishbase this species may reach 40 cm, but typically reaches no more than 20 cm.

Fig 5 : A shoal of Siganus sp. at Pangkor Laut, Peninsular Malaysia.


References :

Bos, A. R., Cruz-Rivera, E., & Sanad, A. M. (2016). Herbivorous fishes Siganus rivulatus (Siganidae) and Zebrasoma desjardinii (Acanthuridae) feed on Ctenophora and Scyphozoa in the Red Sea. Marine Biodiversity, 47(1), 243-246.

Bos, A. R., & Fransen, C. H. (2018). Nocturnal cleaning of sleeping rabbitfish, Siganus canaliculatus, by the cleaner shrimp, Urocaridella antonbruunii (Decapoda, Palaemonidae). Crustaceana, 91(2), 239-241.

Hasse, J. J., Madraisau, B. B., & McVey, J. P. (1977). Some aspects of the life history of Siganus canaliculatus (Park) (Pisces: Siganidae) in Palau. Micronesica, 13(2), 297-312.


Links :

Fishbase - Siganidae

Thanks to Tan Heok Hui and Kelvin Lim for helping with identification.