Trident Goby, Tridentiger trigonocephalus (Gill 1860)

Other Names: Chameleon Goby, Japanese Goby, Striped Tripletooth Goby

A Trident Goby, Tridentiger trigonocephalus, at Jawbone Marine Reserve, Hobsons Bay, Port Phillip, Victoria. Source: Julian K. Finn. License: Copyright: Julian K. Finn / All rights reserved


The Trident Goby is native to Korea, China and Japan where it inhabits sandy areas in seagrass beds. The species was accidentally introduced to Australia as juveniles or larvae in ship ballast water, or via eggs laid on the hulls of ships. Ships heading to Australia must now release their ballast water far offshore.

Identifying features:
Head depressed, much broader than deep, with a broad interorbital space, mout large, oblique;
Overall greyish to brown, with white speckles on head;
Body usually with two distinct black stripes, one from above eye along back to cadual-fin base, the other from snout through eye to caudal fin, stripes often broken by irregular vertical bands, or absent in large fish above 9 cm, adults with a broad yellowish bar at pectoral-fin base.

Cite this page as:
Bray, D.J. 2021, Tridentiger trigonocephalus in Fishes of Australia, accessed 22 Jun 2024,

Trident Goby, Tridentiger trigonocephalus (Gill 1860)

More Info


Native to Korea, China and Japan. Accidentally introduced to Australia from Japan via ship ballast water. The species has been recorded in Sydney Harbour and Port Kembla (New South Wales), Port Phillip (Victoria), the Port River System near Adelaide (South Australia) and Bunbury to the Swan River (Western Australia).

The Trident Goby can tolerate salinites ranging from fresh to marine habitats. In Australia, it is occurs in estuaries, ports and harbours - usually in disturbed areas on sandy bottoms and rocky areas near algae or seagrass beds, including wharf pylons. In Port Phillip, individuals often appear at dusk in the upper reaches, such as around Williamstown.


Dorsal fin VI, I, 12-13; Anal fin I, 10-11; Caudal fin 17; Pectoral fin 18-22; Pelvic fin I, 5.

Body slender, head moderate (27‑31% SL), depressed, much broader than deep; interorbital broad, about equal to or slightly less than eye diameter; mouth oblique, large, rear end of jaws below middle of eyes in young, below posterior quarter of eyes in adults; one pore by each nostril, two pores between front of eyes, median pore between rear end of eyes, pore behind upper quarter of each eye and pore behind middle of each eye; pore above rear end of preopercles, short detached tube with pore at each end above each operculum and three preopercular pores on each side; gilt openings restricted to pectoral fin bases; tongue tip rounded.

Top of head scaled to behind eyes, 19‑21 transverse rows of scales before first dorsal fin origin, rest of head without scales; body scales ctenoid, except on belly, in 45‑55 vertical rows; pectoral fin bases and area before ventral fins scaled.

Two dorsal fins, first dorsal low with rounded margin, originating above and just behind ventral fin insertions; second dorsal origin just behind first dorsal fin; anal fin origin below and just behind second dorsal origin; caudal fin margin rounded. Pectoral fins with tips of upper two rays free from membrane, margin of fin rounded. Pelvic fins fused to form cup­-shaped disc, originating below and just behind pectoral fin insertions.


To 12 cm.


Greyish to brown, usually with a black stripe from behind each eye along the back to base of caudal fin; a second black stripe from snout, through eye, to upper portion of each pectoral fin base, continuing on middle of side to base of caudal fin, stripes often absent in large fish; fins clear to grey; dorsal fins often with brown horizontal stripes and scattered white spots; anal fin often with grey to orange stripe along middle of fin; caudal fin often with wavy brown vertical bars and scattered white spots; adults with broad yellow vertical bar at base of each pelvic fin.


Although the intensity of the distinctive stripes on the body of this species can be regulated by the fish in life, these stripes normally disappear altogether in fish longer than 9 cm.

In 1971, the Trident Goby was first discovered in Sydney Harbour. It was later found in Perth in 1976, and then in Melbourne in 1977. The species is known only form bays and harbours, and has been found in sea water ballast tanks on ships. It is thought therefore to have been accidentally transported to Australia by ships several times from Japan or Taiwan. The species has also been introduced to California, being first discovered in Los Angeles in 1960.


The specific name is from the Latin trigonos (= triangular) and cephalus (= head), in reference to the triangular shape of the oblong head.

Species Citation

Triaenophorus trigonocephalus Gill, 1860, Ann. Lyceum Nat. Hist. New York 7: 19. Type locality: Hong Kong.


Bray, D.J. 2021


Atlas of Living Australia

Trident Goby, Tridentiger trigonocephalus (Gill 1860)


Akihito, P. & Sakamoto, K. 1989. Reexamination of the status of the striped goby. Japanese Journal of Ichthyology 36(1): 100-112 figs 1-7

Carlton, J.T. 1985. Transoceanic and interoceanic dispersal of coastal marine organisms: the biology of ballast water. Oceanography and Marine Biology: Annual Review 1985(23): 313-371.

Gill, H.S. & Potter, I.C. 1993, Spatial segregation amongst goby species within an Australian estuary, with a comparison of the diets and salinity tolerance of the two most abundant species. Marine Biology 117: 515-526.

Gill, T.N. 1860. Prodromus descriptionis familiae Gobioidarum duorum generum novorum. Annals of the Lyceum of Natural History New York 7: 16-19 See ref at BHL

Hammer, M.P. 2006. Range extensions for four estuarine gobies (Pisces: Gobiidae) in Southern Australia: Historically overlooked native taxa or recent arrivals? September. Transactions of the Royal Society of South Australia 130(2): 187-196

Hayes, K., Sliwa, C., Migus, S., McEnnulty, F. & Dunstan, P. 2005. National priority pests: Part II Ranking of Australian marine pests. An independent report undertaken for the Department of Environment and Heritage by CSIRO Marine Research.

Hoese, D.F. 1973. The introduction of the gobiid fishes Acanthogobius flavimanus and Tridentiger trigonocephalus into Australia. Koolewong 2(3): 3-5 1 fig.

Hoese, D.F. & Larson, H.K. 1994. Family Gobiidae. pp. 781-810, figs 690-714 in Gomon, M.F., Glover, C.J.M. & Kuiter, R.H. (eds). The Fishes of Australia's South Coast. Adelaide : State Printer 992 pp. 810 figs.

Hutchins, J.B. & Swainston, R. 1986. Sea Fishes of Southern Australia. Complete field guide for anglers and divers. Perth : Swainston Publishing 180 pp.

Kuiter, R.H. 1993. Coastal Fishes of South-eastern Australia. Bathurst : Crawford House Press 437 pp.

Lockett, M.M. & Gomon, M.F. 2001. Ship mediated fish invasions in Australia: two new introductions and a consideration of two previous invasions. Biological Invasions 3: 187-192

Paxton, J.R. & Hoese, D.F. 1985. The Japanese sea bass, Lateolabrax japonicus (Pisces, Percichthyidae), an apparent marine introduction into Australia. Japanese Journal of Ichthyology 31(4): 369-372 fig. 1

Gill, T.N. 1860. Prodromus descriptionis familiae Gobioidarum duorum generum novorum. Annals of the Lyceum of Natural History New York 7: 16-19.

Watson, W. 1996. Gobiidae: gobies. p. 1214-1245. In H.G. Moser (ed.) The early stages of fishes in the California Current Region. California Cooperative Oceanic Fisheries Investigations (CalCOFI) Atlas No. 33. Allen Press, Inc., Lawrence, Kansas. 1505 pp.

Wonham, M.J., Carlton, J.T., Ruiz, G.M. & Smith, L.D. 2000. Fish and ships: relating dispersal frequency to success in biological invasions. Marine Biology 136: 1111-1121.

Quick Facts

CAAB Code:37428264

Habitat:Sandy, shelly, muddy bottoms

Habitat:Upper reaches of bays, harbours

Max Size:12 cm


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