An Indo-Pacific cardinalfish genus with at least 9 species, 3-4 found in Australian waters. The genus is currently under study and is poorly known in Australia.
Originally described by Jordan & Evermann in 1905, Foa is diagnosed by a combination of internal and osteological characters.
Species of Foa have the following colour patterns: body almost uniformly dark brownish to reddish, often variably marked with whitish or brownish spot, without ocellae or ocellae-like spots on the head and body or in the fins; pelvic fins with whitish outer rays, middle rays darkish with narrow margin of inner rays lighter; membranes of the first four dorsal-fin spines variably marked with many narrow whitish marks or with a pale zone bordered by blackish membranes distally and proximally; caudal, soft dorsal and anal fins with pale membranes and fin rays or with short, narrow brownish to reddish marks on the fin rays interrupting pale regions forming radiated bar-like appearances on the caudal fin or stripe-like appearances on the soft dorsal and anal fins (Fraser & Randall 2011).
Allen, G.R. 1999. Apogonidae. pp. 2602-2610 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.
Eschmeyer, W.N. (ed). Catalog of Fishes. California Academy of Sciences (http://research.calacademy.org/research/ichthyology/catalog/fishcatmain.asp). Electronic version accessed 11 July 2012.
Fraser, T.H. & J.E. Randall. 2011. Two new species of Foa (Apogonidae) from the Pacific Plate, with redescriptions of Foa brachygramma and Foa fo. Zootaxa 2988: 1–27.
Fraser, T.H. 1972. Comparative osteology of the shallow water cardinal fishes [Perciformes: Apogonidae] with reference to the systematics and evolution of the family. Ichthyological Bulletin of the J. L. B. Smith Institute of Ichthyology 34: i-v + 1-105, Pls. 1-44.
Jordan, D.S. & Evermann, B.W. in Jordan, D.S. & Seale, A. 1905. List of fishes collected by Dr. Bashford Dean on the island of Negros, Philippines. Proceedings of the United States National Museum 28(1407): 769-803 figs 1-20 .
Jordan, D.S. & Evermann, B.W. 1905. The aquatic resources of the Hawaiian Islands. I. The shore fishes of the Hawaiian Islands, with a general account of the fish fauna. Bulletin of the United States Fish Commission 23(1): 1-574 figs 1-229 pls 1-65 col. pls 1-73