The family Isonidae comprises the genus Iso with five species, confined to the Indo-Pacific. A single species Iso rhothophilus occurs in Australia waters where it is found in the surf zone.
Surf sardines have a distinctive deep head and anterior that tapers to a slender caudal peduncle, pectoral fins inserted high on the body, usually two separate dorsal fins and a broad, silver mid-lateral stripe. Little is known of their biology.
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.
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