Rabbitfish

{{Short description|Genus of fishes}} {{For|the cartilaginous fish also known as rabbitfish|Rabbit fish}} {{Automatic taxobox | image = 2 Siganus rivulatus Creta2011 7597c.JPG | image_caption = Marbled spinefoot (''Siganus rivulatus'') | image2 = Siganus vulpinus 1 edit.jpg | image2_caption = Foxface rabbitfish (''S. vulpinus'') | display_parents = 3 | taxon = Siganus | authority = Fabricius, 1775<ref name = CofF>{{Cof family | family = Siganidae | access-date = 21 August 2021}}</ref> | type_species = ''Siganus rivulatus'' | type_species_authority = Fabricius, 1775<ref name = CofF/> | subdivision_ranks = Species | subdivision = About 29, see text | synonyms_ref = <ref name = CofF/><ref>{{cite journal |last1=Kottelat |first1=Maurice |title=The Fishes of the Inland Waters of Southeast Asia: A Catalogue and Core Bibliography of the Fishes Known to Occur in Freshwaters, Mangroves and Estuaries |date=2013 |isbn=978-2-8399-1344-7 |journal=The Raffles Bulletin of Zoology |volume=Supplement 27 |pages=439–440 |url=https://lkcnhm.nus.edu.sg/app/uploads/2017/04/rbz_S27.pdf}}</ref> | synonyms = {{Collapsible list| *''Amphacanthus'' Bloch & Schneider, 1801 * ''Amphiscarus'' Swainson, 1839 * ''Buro'' Lacépède, 1803 * ''Buronus'' Rafinesque, 1815 * ''Centrogaster'' Houttuyn, 1782 * ''Lo'' Seale, 1906 * ''Siganites'' Fowler, 1904 * ''Teuthis'' Linnaeus, 1766 }} }}

'''Rabbitfishes''' or '''spinefoots''', genus '''''Siganus''''', are perciform fishes in the family Siganidae. It is the only extant genus in its family and has 29 species. In some now obsolete classifications, the species having prominent face stripes—colloquially called '''foxfaces'''–are in the genus ''Lo''. Other species, such as the masked spinefoot (''S. puellus''), show a reduced form of the stripe pattern. Rabbitfishes are native to shallow waters in the Indo-Pacific, but ''S. luridus'' and ''S. rivulatus'' have become established in the eastern Mediterranean via Lessepsian migration. They are commercially important food fish, and can be used in the preparation of dishes such as ''bagoong''.

==Taxonomy== The genus ''Siganus'' was described in 1775 by the Danish zoologist Johan Christian Fabricius with ''Siganus rivulatus'', a species also described by Fabricius in 1775, designated as the type species. The description was based on notes taken by the naturalist Peter Forsskål when he was on the Danish Arabia expedition (1761–67) and was published in Carsten Niebuhr's ''Descriptiones animalium avium, amphibiorum, piscium, insectorum, vermium; quae in itinere orientali observavit Petrus Forskål. Post mortem auctoris edidit Carsten Niebuhr''. Catalog of Fishes lists the authority as " Fabricius [J. C.] (ex Forsskål) in Niebuhr 1775" and states that the genus is valid as "''Siganus'' Fabricius 1775".<ref name = CofF/>

Carl Linnaeus originally described the genus ''Teuthis'', with the type species being ''Teuthis hepatus''. One of the type specimens he used looks like ''Siganus javus'', although the other is definitely not a rabbitfish, and the International Commission on Zoological Nomenclature has been asked to suppress the name ''Teuthis'' in favour of ''Siganus'' to reflect the prevailing usage.

The name ''Siganus'' is a latinisation of the local Arabic name for the marbled rabbitfish (''S. rivulatus'') in Yemen, ''Sidjan'' which can also be written as ''Sigian'', and means "rabbitfish".<ref name = ETYFish>{{cite web | url = https://etyfish.org/acanthuriformes2/| title = Order Acanthuriformes (part 2): Families Ephippidae, Leiognathidae, Scatophagidae, Antigoniidae, Siganidae, Caproidae, Luvaridae, Zanclidae and Acanthuridae | work = The ETYFish Project Fish Name Etymology Database | editor1= Christopher Scharpf | editor2 = Kenneth J. Lazara | name-list-style = amp |date = 12 January 2021 | access-date = 21 August 2021 | publisher = Christopher Scharpf and Kenneth J. Lazara}}</ref>

In 2007 Kurriwa ''et al.'', outlined a way to split the genus—if the scientific community so desires:<ref name = kuriiwaetal2007>{{cite journal | author1 = Kaoru Kuriiwaa | author2 =Naoto Hanzawab | author3 = Tetsuo Yoshinoc| author4 = Seishi Kimurad | author5 = Mutsumi Nishida | name-list-style = amp | year = 2007 | title = Phylogenetic relationships and natural hybridization in rabbitfishes (Teleostei: Siganidae) inferred from mitochondrial and nuclear DNA analyses | journal = Molecular Phylogenetics and Evolution | volume = 45 | issue =1 | pages = 69–80 | doi = 10.1016/j.ympev.2007.04.018}}</ref> * An ancient group containing e.g. ''S. woodlandi'' * Another fairly small group containing, e.g., the ''S. canaliculatus''/''S. fuscescens'') complex * The remainder of'' Siganus'', including the foxfaces

Other lineages might exist and make obsolete the somewhat weak distinction between the second and third groups. Also, it is not known where the type species ''S. rivulatus'' would fall, hence names for these three subgenera or genera are not established at present.

Hybridizaton has played a role in the evolution of the Siganidae, as evidenced by comparison of mtDNA cytochrome ''b'' and nDNA internal transcribed spacer 1 sequence data. Evidence exists of interbreeding between ''S. guttatus'' and ''S. lineatus'', as well as between ''S. doliatus'' and ''S. virgatus''.<ref name = kuriiwaetal2007 />

Also, either females of the last common ancestor of ''S. puellus'' and the ''S. punctatus'' interbred with females ancestral to the main non-foxface lineage, or males of the former hybridized with females of the last common ancestor of ''S. punctatissimus'' and the foxfaces, while males of the latter mated with females of the original foxface species.<ref name = kuriiwaetal2007 />

An individual was found that looked like a slightly aberrant blue-spotted spinefoot (''S. corallinus''). On investigation, it turned out to be an offspring of a hybrid between a female of that species and a male masked spinefoot, which had successfully backcrossed with the blue-spotted spinefoot.<ref name = kuriiwaetal2007 />

===Species=== As noted above, several presumed species are suspected to actively interbreed even today; these might warrant merging as a single species. This applies to the white-spotted spinefoot (''S. canaliculatus'') and the mottled spinefoot (''S. fuscescens''), and to the blotched foxface (''S. unimaculatus'') and the foxface rabbitfish (''S. vulpinus''). Alternatively they might be very recently evolved species that have not yet undergone complete lineage sorting, but their biogeography suggests that each group is just color morphs of a single species. On the other hand, the morphologically diverse blue-spotted spinefoot (''S. corallinus'') might represent more than one species; orange individuals are found at the north of its range, while yellow ones occur to the south, and these two may be completely parapatric.<ref name = kuriiwaetal2007 />

There are currently 29 recognized species in this genus:<ref name = Fishbase2>{{FishBase genus | genus = Siganus | month= June | year = 2021}}</ref> {| class="wikitable" |+ !Species !Common name !Image |- |''Siganus argenteus'' (Quoy & Gaimard, 1825) |Streamlined spinefoot |frameless |- |''Siganus canaliculatus'' (M. Park, 1797) |White-spotted spinefoot | |- |''Siganus corallinus'' (Valenciennes, 1835) |Blue-spotted spinefoot |{{CSS image crop|Image=Coral rabbitfish (Siganus corallinus) (45912423451).jpg|bSize=250|cHeight=140|oTop=40}} |- |''Siganus doliatus'' Guérin-Méneville, 1829 |Barred spinefoot |frameless |- |''Siganus fuscescens'' (Houttuyn, 1782) |Mottled spinefoot |{{CSS image crop|Image=Siganus fuscescens 1.jpg|bSize=250|cHeight=140|oTop=15}} |- |''Siganus guttatus'' (Bloch, 1787) |Goldlined spinefoot |{{CSS image crop|Image=Siganus guttatus Golden Rabbitfish.jpg|cHeight=130|bSize=250|oTop=25}} |- |''Siganus insomnis'' Woodland & R. C. Anderson, 2014 |Bronze-lined rabbitfish |frameless |- |''Siganus javus'' (Linnaeus, 1766) |Streaked spinefoot |frameless |- |''Siganus labyrinthodes'' (Bleeker, 1853) |Labyrinth spinefoot | |- |''Siganus laqueus'' von Bonde 1934<ref>{{Cite web |title=CAS - Eschmeyer's Catalog of Fishes |url=https://researcharchive.calacademy.org/research/ichthyology/catalog/fishcatget.asp?spid=53331 |access-date=2025-12-18 |website=researcharchive.calacademy.org}}</ref> |Brown spotted rabbitfish |frameless |- |''Siganus lineatus'' (Valenciennes, 1835) |Golden-lined spinefoot |{{CSS image crop|Image=Lined rabbitfish (Siganus lineatus).jpg|bSize=250|cHeight=120|oTop=40}} |- |''Siganus luridus'' (Rüppell, 1829) |Dusky spinefoot |frameless |- |''Siganus magnificus'' (G. H. Burgess, 1977) |Magnificent rabbitfish |frameless |- |''Siganus niger'' Woodland, 1990 |Black foxface | |- |''Siganus puelloides'' Woodland & Randall, 1979 |Blackeye rabbitfish |frameless |- |''Siganus puellus'' (Schlegel, 1852) |Masked spinefoot |frameless |- |''Siganus punctatissimus'' Fowler & B. A. Bean, 1929 |Peppered spinefoot |{{CSS image crop|Image=Finespotted rabbitfish (Siganus punctatissimus) (47615725181).jpg|bSize=250|oTop=30|cHeight=140}} |- |''Siganus punctatus'' (Schneider & Forster, 1801) |Goldspotted spinefoot |{{CSS image crop|Image=Goldspotted spinefoot Saltwater Fish 3008px.jpg|cHeight=130|oTop=20|bSize=250}} |- |''Siganus randalli'' Woodland, 1990 |Variegated spinefoot | |- |''Siganus rivulatus'' Forsskål & Niebuhr, 1775 |Marbled spinefoot |frameless |- |''Siganus spinus'' (Linnaeus, 1758) |Little spinefoot |frameless |- |''Siganus stellatus'' (Forsskål, 1775) |Brown-spotted spinefoot |frameless |- |''Siganus sutor'' (Valenciennes, 1835) |Shoemaker spinefoot |{{CSS image crop|Image=Siganus sutor 19249030.jpg|bSize=250|cHeight=130|oTop=30}} |- |''Siganus trispilos'' Woodland & G. R. Allen, 1977 |Threeblotched rabbitfish |{{CSS image crop|Image=Siganus trispilos 411722896.jpg|cHeight=120|oTop=35|bSize=250}} |- |''Siganus unimaculatus'' (Evermann & Seale, 1907) |Blotched foxface |frameless |- |''Siganus uspi'' Gawel & Woodland, 1974 |Bicolored foxface |frameless |- |''Siganus vermiculatus'' (Valenciennes, 1835) |Vermiculated spinefoot |{{CSS image crop|Image=Vermiculate rabbitfish (Siganus vermiculatus) - 50154095456.jpg|bSize=250|cHeight=130|oTop=35}} |- |''Siganus virgatus'' (Valenciennes, 1835) |Barhead spinefoot |frameless |- |''Siganus vulpinus'' (Schlegel & J. P. Müller, 1845) |Foxface |{{CSS image crop|Image=Siganus vulpinus 2.jpg|bSize=250|oTop=10|cHeight=130}} |- |''Siganus woodlandi'' Randall & Kulbicki, 2005 | | |}

==Characteristics== thumb|''S. fuscescens'' (Mottled spinefoot), Australia Rabbitfishes have laterally compressed, oval bodies which may be deep, or slender. A few species have a tubular snout. The mouth is very small and is with non protractile jaws which have one row of compressed, closely set, incisor-like teeth in each jaw. The teeth overlap slightly and create a beak like structure. The dorsal fin has 13 robust spines and 10 soft rays and the front spine is short, sharp and points forward, sometimes projecting from its "pocket" but it may be enfolded. The anal fin has 7 robust spines and 9 soft rays. The pelvic fins have 2 spines with 3 soft rays between them; this characteristic is unique to the Siganidae. There is a membrane which extends from the inner pelvic fin spine to the belly with the anus sitting between these membranes. The tiny scales are cycloid and may be absent from the head region. If present on the head they are restricted to a small area of the cheek under the eye.<ref name = FAO>{{cite book | editor1 = Carpenter, K.E. | editor2 = Niem, V.H. | name-list-style = and | title = FAO species identification guide for fishery purposes. The living marine resources of the Western Central Pacific. Volume 6. Bony fishes part 4 (Labridae to Latimeriidae), estuarine crocodiles, sea turtles, sea snakes and marine mammal | publisher = FAO Rome | year = 2001 | chapter = Siganidae | author = D.J. Woodland | page = 3627 | isbn = 92-5-104587-9 |url = https://www.fao.org/3/y0870e/y0870e27.pdf}}</ref>

They range in maximum total lengths of {{cvt|20|cm}} in the case of the blotched foxface (''S. unimaculatus'') to {{cvt|53|cm}} in the streaked spinefoot (''S. javus'').<ref name="Fishbase" />

=== Venom === {{Easy CSS image crop|Image=20131016 103320 Zoo Vienna.jpg|caption=Closeup of the venomous dorsal spines, in ''Siganus magnificus''|desired_width=250|crop_left_perc=36|crop_right_perc=20|crop_top_perc=10|crop_bottom_perc=50}} Rabbitfish have venomous spines in the dorsal and pelvic fins. In at least three species, the venom has been found to be similar to that found in stonefish.<ref name="venom">{{cite journal | author1 = Kiriake A | author2 = Ishizaki S | author3 = Nagashima Y | author4 = Shiomi K | title = Occurrence of a stonefish toxin-like toxin in the venom of the rabbitfish ''Siganus fuscescens'' | journal = Toxicon | year = 2017 | volume = 140 | pages = 139–146 | doi = 10.1016/j.toxicon.2017.10.015 | pmid = 29055787}}</ref><ref>{{Cite journal |last=Yoshinaga-Kiriake |first=Aya |last2=Nagashima |first2=Yuji |last3=Ishizaki |first3=Shoichiro |last4=Shiomi |first4=Kazuo |date=2020-09-01 |title=Primary structures and conformations of stonefish toxin-like toxins from three species of rabbitfish, Siganus puellus, Siganus unimaculatus, and Siganus virgatus |url=https://doi.org/10.1007/s12562-020-01455-9 |journal=Fisheries Science |language=en |volume=86 |issue=5 |pages=889–901 |doi=10.1007/s12562-020-01455-9 |issn=1444-2906|url-access=subscription }}</ref> The fin spines are equipped with well-developed venom glands. The sting is very painful, but it is generally not considered medically significant in healthy adults.<ref name="Lieske">{{cite book | author1 = Lieske, E. | author2 = Myers, R. | name-list-style = amp | year = 1999 | title = Coral Reef Fishes | edition = 2 | publisher = Princeton University Press | pages = 129–130 | isbn = 0-691-00481-1}}</ref><ref name="Taylor">{{cite journal | last = Taylor | first = Geoff | year = 2000 | title = Toxic fish spine injury: Lessons from 11 years experience | journal = Journal of the South Pacific Underwater Medical Society | volume = 30 | issue =1 | pages = 7–8}}</ref>

==Distribution and habitat== Rabbitfishes are found in the Indo-Pacific from the Red Sea and the coast of eastern Africa through the Pacific Ocean as far as Pitcairn Island.<ref name = Fishbase2/> Two Red Sea species ''S. rivulatus'' and ''S. luridus'' have invaded the Mediterranean Sea through the Suez Canal, a process known as Lessepsian migration.<ref name = Debelius>{{cite book | author = Debelius, H. | year = 1997 | title = Mediterranean and Atlantic Fish Guide | isbn = 978-3925919541}}</ref><ref name = CofF2>{{Cof genus | genus = Siganus | access-date = 21 August 2021}}</ref> These fishes are found in inshore tropical and subtropical waters where they occur in reefs, lagoons, mangroves and seagrass beds.<ref name = FofA>{{cite web | author = Dianne J. Bray | title = Rabbitfishes, Siganidae | work = Fishes of Australia | access-date = 21 August 2021 | url = https://fishesofaustralia.net.au/home/family/17 | publisher = Museums Victoria}}</ref>

==Biology== thumb|right|A school of ''S. spinus'' (Little spinefoots)All rabbitfish are diurnal; some live in schools, while others live more solitary lives among the corals. Rabbitfish sleep in crevices in the reef matrix at night. While sleeping, the rabbitfish ''Siganus canaliculatus'' was observed being cleaned by the cleaner shrimp ''Urocaridella antonbruunii''.<ref>{{cite journal |author= A.R. Bos |author2=C.J.H.M. Fransen |year=2018 |title=Nocturnal cleaning of sleeping rabbitfish, ''Siganus canaliculatus'', by the cleaner shrimp ''Urocaridella antonbruunii'' (Decapoda: Palaemonidae) |journal= Crustaceana |volume=91 |issue=2 |pages=239–241 |url=https://www.researchgate.net/publication/320629136|doi=10.1163/15685403-00003753 }}</ref> They are herbivorous, feeding on benthic algae in the wild. However, ''Siganus rivulatus'' was recently observed feeding on jellyfish (Scyphozoa) and comb jellies (Ctenophora) in the Red Sea.<ref>{{cite journal |author=Bos A.R. |author2=Cruz-Rivera E. |author3=Sanad A.M. |year=2016 |title=Herbivorous fishes ''Siganus rivulatus'' (Siganidae) and ''Zebrasoma desjardinii'' (Acanthuridae) feed on Ctenophora and Scyphozoa in the Red Sea |journal=Marine Biodiversity |volume=47 |issue=1 |pages=243–246 |doi=10.1007/s12526-016-0454-9 |s2cid=24694789 |url=https://www.researchgate.net/publication/291813803 }}</ref> Also ''Siganus fuscescens'' have been observed eating prawns and other baits, suggesting that some species are opportunistic omnivorous feeders. The live passage of benthic organisms in the guts of invasive rabbitfish (ichthyochory) was shown to play a major role in the long distance dispersal and bioinvasion of foraminifera.<ref>{{Cite journal|last1=Guy-Haim|first1=Tamar|last2=Hyams-Kaphzan|first2=Orit|last3=Yeruham|first3=Erez|last4=Almogi-Labin|first4=Ahuva|last5=Carlton|first5=James T.|date=2017-06-01|title=A novel marine bioinvasion vector: Ichthyochory, live passage through fish|journal=Limnology and Oceanography Letters|language=en|volume=2|issue=3|pages=81–90|doi=10.1002/lol2.10039|issn=2378-2242|doi-access=free}}</ref> Rabbitfish lay adhesive eggs and some species live as monogamous pairs.<ref name = FAO/>

==Utilization== Rabbitfish can be important species for commercial fisheries, particularly the schooling species. The catch is largely sold fresh but juveniles may be dried or processed to make fish paste. Some species are used in aquaculture and some of the more colorful species are found in the aquarium trade.<ref name = FAO/> Some species have been reported to be hallucinogenic.<ref name="Halstead1973">Halstead BW, Cox KM (1973) [https://books.google.com/books?id=opULAQAAIAAJ "An investigation on fish poisoning in Mauritius"], ''Proc Roy Soc Arts Sci Mauritius'', '''4''' (2): 1–26.</ref><ref>[http://eol.org/pages/214691/details ''Siganus argenteus'': Yellowspotted Spinefoot ] ''Encyclopedia of Life''. Retrieved 23 October 2013.</ref><ref>{{FishBase |genus=Siganus |species=argenteus |year=2013 |month=October}}</ref>

==References== {{Reflist|refs= <ref name = Fishbase>{{FishBase family|family=Siganidae|month=October|year=2023}}</ref> }}

Category:Siganidae Category:Venomous fish Category:Taxa named by Johan Christian Fabricius