Surf Sardine, Iso rhothophilus (Ogilby 1895)

Other Names: Flower of the Wave, Flower of the Waves, Surf Fish, Surf-fish, Sydney Surf Fish

A Surf Sardine, Iso rhothophilus. Source: Rudie H. Kuiter / Aquatic Photographics. License: All rights reserved

Small translucent silvery fishes with a broad silver mid-lateral stripe terminating on a small oval spot before the caudal fin, and sometimes darker pigment on the top of the head and opercle. 

Cite this page as:
Bray, D.J. 2021, Iso rhothophilus in Fishes of Australia, accessed 02 Dec 2022,

Surf Sardine, Iso rhothophilus (Ogilby 1895)

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Fraser Island, Queensland, to Kilcunda, Victoria, the Gulf St Vincent, South Australia, and the Recherche Archipelago to Rottnest Island, Western Australia; also the Lord Howe Province in the Tasman Sea. Elsewhere the species occurs in New Zealand.
Forms schools in the high-energy surf zone around rocky headlands and along the shoreline; also occasionally in tidal inlets and river mouths.


Dorsal fin III-VI + I,10-17; Anal fin I,20-28; Pectoral fin I,13-16; Caudal fin 17; Gill rakers 9-14 (lower limb); Midlateral scales 42-55; Vertebrae 38-45.Body highly compressed, deep anteriorly (19-33% SL), tapering to a narrow caudal peduncle (17-24% SL), greatest body depth at vertical through origin of pectoral fins; ventral edge of abdomen reduced to sharp keel. Dorsal profile almost straight; head small (17-24% SL), rounded; snout short (55-142% eye diameter); eyes moderately large (27-42% HL), interorbital broad (27-40% HL). Mouth small, obliquely angled, reaching beyond anterior margin of eye, upper jaw not protrusible, ascending process of premaxilla small, fixed, dentaries greatly elevated posteriorly, forming scoop-like  structure; teeth minute, in single row, covering about half free edge of premaxilla; gill raker length about equal to diameter of pupil of eye.Two dorsal fins, 1st small, short-based, centered on back, widely separated from longer-based 2nd dorsal fin ; anal fin longer than 2nd dorsal fin, caudal fin forked. Pectoral fins short, inserted above middle of side. Pelvic fins tiny, positioned below and just behind pectoral-fin base. 
Body scales small, absent from predorsal and abdominal regions; lateral line absent; head with denticles frequently extending beyond jaws to top of snout. Pleural ribs clearly visible through the skin.


7.5 cm TL


Silvery and translucent, with solid, broad silvery midlateral stripe terminating in an oval spot before the caudal fin; top of head and opercle sometimes slightly darker than rest of body.


Extremely delicate fish, easily damaged by handling; can be locally abundant in the surf zone near rocky outcrops or along the shoreline, occasionally in river mouths, but infrequently caught due to rough conditions. Surf Sardines do not survive in areas with low oxygen concentrations.

Species Citation

Tropidostethus rhothophilus Ogilby 1895, Proceedings of the Linnean Society of New South Wales 2 10(2): 323. Type locality: Maroubra Bay between Port Jackson and Botany Heads, New South Wales.


Bray, D.J. 2021


Atlas of Living Australia

Surf Sardine, Iso rhothophilus (Ogilby 1895)


Allen, G.R., Hoese, D.F., Paxton, J.R., Randall, J.E., Russell, B.C., Starck, W.A., Talbot, F.H. & Whitley, G.P. 1976. Annotated checklist of the fishes of Lord Howe Island. Records of the Australian Museum 30(15): 365-454 figs 1-2

Bloom, D.D., Unmack, P.J., Gosztonyi, A.E., Piller, K.R. & Lovejoy, N.R. 2012. It’s a family matter: Molecular phylogenetics of Atheriniformes and the polyphyly of the surf silversides (Family: Notocheiridae). Molecular Phylogenetics and Evolution 62: 1025-1030

Campanella, D., Hughes, L.C., Unmack, P.J., Bloom, D.D., Piller, K.R. &  Ortí, G. 2015. Multi-locus fossil-calibrated phylogeny of Atheriniformes (Teleostei, Ovalentaria). Molecular Phylogenetics and Evolution 86: 8-23,

Francis, M.P. 1993. Checklist of the coastal fishes of Lord Howe, Norfolk, and Kermadec Islands, Southwest Pacific Ocean. Pac. Sci. 47(2): 136-170.

Hoschke, A., Whisson, G. & Moore, G.I. 2019. Complete list of fishes from Rottnest Island. pp. 150-161 in Whisson, G. & Hoschke, A. (eds) The Rottnest Island fish book. 2nd ed. Perth _ Aqua Research and Monitoring Services.

Humphries, P., Hyndes, G.A. & Potter, I.C. 1992. Comparisons between the diets of distant taxa (Teleost and Cormorant) in an Australian estuary. Estuaries 15(3):327-334.

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

Hutchins, J.B. & Thompson, M. 1983. The Marine and Estuarine Fishes of South-western Australia. Perth : Western Australian Museum 103 pp. 345 figs.

Ivantsoff, W. 1994. Families Atherinidae, Isonidae. pp. 375-383 figs 336-342 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.

Ivantsoff, W. 1999. Isonidae, Telmatherinidae, Dentatherinidae. pp. 2140-2145 in Carpenter, K.E. & Niem, T.H. (eds). The Living Marine Resources of the Western Central Pacific. FAO Species Identification Guide for Fisheries Purposes. Rome : FAO Vol. 4 2069-2790 pp.

Johnson, J.W. 2010. Fishes of the Moreton Bay Marine Park and adjacent continental shelf waters, Queensland, Australia. pp. 299-353 in Davie, P.J.F. & Phillips, J.A. Proceedings of the Thirteenth International Marine Biological Workshop, The Marine Fauna and Flora of Moreton Bay. Memoirs of the Queensland Museum 54(3)

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

Ogilby, J.D. 1895. On two new genera and species of fishes from Australia. Proceedings of the Linnean Society of New South Wales 2 10(2): 320-324.

Raadik, T.A. 2008. Family Isonidae. pp. 401 in Gomon. M.F., Bray, D.J. & Kuiter, R.H (eds). Fishes of Australia's Southern Coast. Sydney : Reed New Holland 928 pp.

Saeed, B., Ivanstoff, W., Aarn 2006. Descriptive anatomy of Iso rhothophilus (Ogilby), with a phylogenetic analysis of Iso and a redefinition of Isonidae (Atheriniformes). Aqua, Journal of Ichthyology and Aquatic Biology 11: 25-43.

Saeed, B., Ivantsoff, W. & Crowley, L.E.L.M. 1993. A new species of surf-inhabiting atheriniform Iso (Pisces: Isonidae). Records of the Western Australian Museum 16(3): 337-346.

Schultz, L.P. 1950. Correction for "A revision of six subfamilies of atherine fishes, with descriptions of new genera and species." Copeia 1950(2): 150 (as Tropidostethops rhothophilus)

Senou, H. 2002. Families Atherinidae, Notocheiridae, Poeciliidae and Adrianichthyidae. pp. 1514-1515 in Nakabo, T. (ed.) Fishes of Japan with pictorial keys to the species. English edition. Tokyo : Toikai University Press pp. 867-1749.

Trnski, T. 2015. 125 Family Isonidae. pp. 946-947 in Roberts, C.D., Stewart, A.L. & Struthers, C.D. The Fishes of New Zealand. Wellington : Te Papa Press Vol. 3 pp. 577-1152.

Waite, E.R. 1904. New records or recurrences of rare fishes from eastern Australia. No. 3. Records of the Australian Museum 5(4): 231–244, plates xxv– xxvi.

Whitley, G.P. 1962. Marine Fishes. Natural History of Sydney, Australian Museum. 44-52 pp.

Quick Facts

CAAB Code:37247001

Depth:0-20 m

Habitat:Pelagic in surf zone

Max Size:7.5 cm TL

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