Vermiculated spinefoot (Siganus vermiculatus)

Classification (WoRMS)

Full classification as recorded by WoRMS: Kingdom: Animalia · Phylum: Chordata · Class: Teleostei · Order: Acanthuriformes · Family: Siganidae · Genus: Siganus.

Accepted name: Siganus vermiculatus · Authority: (Valenciennes, 1835) · Taxonomic status: accepted · AphiaID: 273927.

Synonyms and superseded combinations recorded for this taxon: Amphacanthus russelii Valenciennes, 1835; Amphacanthus vermiculatus Valenciennes, 1835; Siganus shortlandensis Seale, 1906; Teuthis vermiculata (Valenciennes, 1835); Teuthis vermiculatus (Valenciennes, 1835).

Source: World Register of Marine Species (WoRMS) — https://www.marinespecies.org/aphia.php?p=taxdetails&id=273927 (CC BY 4.0). Accessed 2026-09-23.

Biology and life history (FishBase)

Measured values published by FishBase for Siganus vermiculatus. Only fields the database actually holds for this species are shown; these are database values, not aquarium guidance.

Maximum length: 45 cm · Common length: 30 cm · Depth range: 0–20 m · Habitat zone: reef-associated · Body shape: short and / or deep · Vulnerability index: 19.6 of 100 · Fishery importance: commercial · Aquarium trade: commercial.

FishBase notes: Juveniles live among mangroves then move out to lagoon and coastal reefs as they mature. Forms schools. Feeds on algae growing on seagrasses, mangrove roots and rocks. Adults congregate inshore in groups of several hundreds to spawn in summer. Spawning is by pairs; sticky eggs laid on the bottom. Its very high quality flesh commands premium prices (Ref. 9813). Adults on coastal reefs, subject to strong currents (Ref. 48637). This species can tolerate very low salinities (2 ppt) and temperatures up to 38 C (Ref. 37816).

Source: FishBase species summary (SpecCode 4561) — https://www.fishbase.se/summary/Siganus-vermiculatus.html (CC BY-NC 3.0 — non-commercial use only). Accessed 2026-09-23.

Distribution and occurrence records (GBIF)

182 georeferenced occurrence records for Siganus vermiculatus are published through GBIF from 20 countries or marine areas. The map above plots 67 distinct locations from a sample of 182 records, omitting 29 inland records that carry an institution's coordinates rather than a collection site; it shows where the species has been observed and reported, not a modelled range.

Most records by country or area: Fiji (33); Indonesia (33); Thailand (23); Philippines (20); India (10); Vanuatu (10); French Polynesia (9); Papua New Guinea (7); Australia (6); Palau (6); New Caledonia (5); Solomon Islands (4); Japan (3); Wallis and Futuna (3); Micronesia (Federated States of) (2).

Marine regions with a valid WoRMS distribution record: Mtwapa.

Source: GBIF Occurrence Search (taxonKey 2390251) — https://www.gbif.org/occurrence/search?taxon_key=2390251&has_coordinate=true (records CC0 / CC BY); WoRMS distribution records (MarineRegions) — https://www.marinespecies.org/aphia.php?p=taxdetails&id=273927 (CC BY 4.0); Natural Earth 110m basemap — https://www.naturalearthdata.com/ (public domain). Accessed 2026-09-23.

Conservation status (IUCN Red List)

The IUCN Red List assesses Siganus vermiculatus (Valenciennes, 1835) as Least Concern (code LC). No trend, population estimate or threat analysis is given here, because none is available from this source without the Red List API; follow the source link for the full assessment, including its date.

Source: IUCN Red List of Threatened Species (taxon 196436) — https://www.iucnredlist.org/species/196436/0; GBIF IUCN Red List category endpoint (taxonKey 2390251) — https://api.gbif.org/v1/species/2390251/iucnRedListCategory. Accessed 2026-09-23.

Description and natural history (Wikipedia)

The vermiculated spinefoot was first formally described in 1835 as Amphacanthus vermiculatus by the French zoologist Achille Valenciennes with the type locality given as New Guinea. The specific name vermiculatus refers to the vermiculated or maze pattern on the bodies of the living fish.

The vermiculated spinefoot has a deep and laterally compressed body which has a depth which fits 1.9 to 2.2 times into its standard length. The nape is bulging with a slight indentation above each eye. The deep, blunt snout also bulges. The front nostril has a flange which is slightly widened to its rear. There is a recumbent spine to the front of the dorsal fin. Like all rabbitfishes, the dorsal fin has 13 spines and 10 soft rays, while the anal fin has 7 spines and 9 soft rays. The fin spines hold venom glands. The caudal fin is emarginate. This species attains a maximum total length of 45 cm, although 30 cm is more typical. The body is covered in a grey and whitish complex maze-like or reticulate pattern with a patch of yellow on the head and spots on the caudal fin.

The vermiculated spinefoot is found from southern India and Sri Lanka eastwards into the western Pacific Ocean as far east as Palau and Guam, south to Vanuatu, Fiji and New Caledonia and Australia. In Australia it has been reported from Darnley Island and Townsville in northern Queensland but its presence in Australian waters needs to be confirmed. It is found in shallow, coastal waters, especially estuaries. Both adults and juveniles are commonest shallow, sediment-laden waters in mangroves, following the tide in and out. Adults are occasionally encountered in clear water in the vicinity of reefs or above sandy substrates.

The vermiculated spinefoot browses algae which is growing on seagrass, the roost of mangrove and on rocks. The adults gather in aggregations of several hundred individuals to spawn in the summer, the pawn in pairs laying eggs which adhere to the substrate. The lunar cycle governs spawning behaviour.

This species produces venom in the spines of its fins. In a study of the venom of a congener (S. fuscescens) it was found that rabbitfish venom was similar to the venom of stonefishes.

The vermiculated spinefoot is a large fast growing species and is sold fresh in markets in India, Sri Lanka and Fiji where it commpans premium prices. They are caught using nets and fixed traps.

Source: Wikipedia: Vermiculated spinefoot — https://en.wikipedia.org/wiki/Vermiculated_spinefoot (CC BY-SA 4.0). Accessed 2026-09-23.