Taxon profile


Wavy-lined Grouper
Epinephelus ongus (Bloch, 1790)

kingdom Animalia - animals »  phylum Chordata - chordates »  class Actinopterygii - ray-finned fishes »  order Perciformes - perch-likes »  family Serranidae - sea basses and groupers »  genus Epinephelus

Scientific synonyms

Holocentrus ongus Bloch, 1790
Serranus bataviensis Bleeker, 1849
Serranus dichropterus Valenciennes, 1828
Epinephelus summana hostiaretis Whitley, 1954
Serranus reticulatus Valenciennes, 1828
Epinephelus slacksmithi Whitley, 1959
Serranus tumilabrus Valenciennes, 1828
Serranus tumilabris Valenciennes, 1828
Serranus tumilebris Valenciennes, 1828

Other names

= White-speckled Rock Cod
= White-streaked Groper
= White-streaked Grouper

Least Concern LC


Body depth contained 2.7 to 3.2 times in standard length (for fish 11 to 25 cm standard length); body width contained 1.7 to 2.2 times in the depth. Head length contained 2.3 to 2.5 times in standard length; head pointed, the interorbital area flat, the dorsal head profile slightly convex; preopercle rounded, the serrae small and mostly covered by skin; upper edge of operculum strongly convex, the rear edge almost vertical, the upper spine extending posterior to lower spine; posterior nostril diameter about twice that of anterior nostril; maxilla reaches to or slightly past vertical at rear edge of eye; small, embedded scales on maxilla; teeth small, 2 to 4 rows at midlateral part of lower jaw; canines at front of jaws small or absent. Gill rakers 8 to 10 on upper limb, 15 to 18 on lower limb (including 6 to 8 rudiments on each limb). Dorsal fin with XI spines and 14 to 16 rays, the third or fourth spine longest, its length contained 2.6 to 3.4 times in head length, the interspinous membranes incised; anal fin with III spines and 8 rays; pectoral fins
large and fleshy, with 15 to 17 rays; pectoral-fin length contained 1.4 to 1.7 in head length; pelvic fins end well short of anus, their length contained 2.0 to 2.3 times in head length: caudal fin rounded. Lateral-body scales ctenoid, with auxiliary scales; lateral-line scales 48 to 53; lateral-scale series 95 to 109.
Colour: Body brown, with numerous small white spots which, in fish larger than 10 cm standard length are horizontally elongate and, in adults, tend to form wavy white lines; several round or irregular pale blotches (eye-sized or larger) usually superimposed over small white spots; head brown, with numerous small white spots dorsally behind eyes; black maxillary streak usually hidden by maxilla; median fins with small white spots and streaks, the posterior margin blackish with a white edge; paired fins greyish brown. Juveniles of about 6 cm standard length are brown, covered with small, dark-edged white spots which are round, except on front part of dorsal fin where they are elongated; the white spots on the paired fins become fewer and fainter with growth, and are absent in adults.


E. ongus is widely distributed in the Indo-Pacific region, from the east coast of Africa (northern Mozambique to Kenya) to the Ryukyu and Marshall Islands and south to Fiji, New Caledonia and northern Australia. It is replaced in the Red Sea by the closely-related endemic E. summana. Most of the verifiable records for E. ongus are from islands, and as far as Heemstra and Randall (1993) know, it does not occur in the Persian Gulf or on the coasts of Arabia, India, Sri Lanka, or Asia. Heemstra and Randall (1993) have examined specimens from Mozambique, Zanzibar, Kenya, Madagascar, Seychelles, Indonesia, Philippines, Ryukyus, New Guinea, Solomon Islands, Australia (northwestern Australia to southern Queensland), Palau Islands, Caroline Islands, Marshall Islands, Santa Cruz Islands, New Hebrides, New Calendonia, and Fiji.


E. ongus occurs in shallow water on coral reefs and rocky substrata. According to Myers (1989) “E. ongus occurs primarily on inner coastal and lagoon reefs, even in brackish water, where it frequents ledges and caves at depths of 5 to 25 m.”


Myers (1989) and Katayama (1988) give a maximum size of 40 cm standard length, but the largest specimen that Heemstra and Randall (1993) have seen was 25 cm standard length (31 cm total length). Sizes over 40 cm that have been attributed to E. ongus probably refer to E. caeruleopunctatus, with which it is often confused.

Interchangeable taxa

E. ongus is closely related to E. summana, which is endemic to the Red Sea. It differs from E. ongus in having shorter pectoral fins (length contained 1.65 to 2.1 times in head length), shorter pelvic fins (length contained 2.2 to 2.7 times in head length), and the posterior nostrils of adults are vertically elongated (their length contained 2 to 4 times diameter of anterior nostrils). The white-edged black margin on the median fins of E. ongus is poorly developed or absent in E. summana. The sympatric E. caeruleopunctatus has a similar colour pattern, but the caudal and anal fins have only a few white spots (confined mainly to proximal part of these fins), and the paired fins of juveniles are mostly unspotted. It also has 17 to 19 pectoral-fin rays, 51 to 61 lateral-line scales, upper edge of operculum sinuous or slightly convex, and the rear nostrils of adults are vertically elongated, their length 5 or 6 times diameter of front nostrils. This species also attains a larger size than E. ongus (at least 60 cm total length).


Food and Agriculture Organization of the United Nations, 1993, Heemstra, P.C.; Randall, J.E., FAO species catalogue. Vol. 16. Groupers of the world (Family Serranidae, Subfamily Epinephelinae). An annotated and illustrated catalogue of the grouper, rock cod, hind, coral grouper and lyretail species known to date.
Author: Petr Čech

Links and literature

CH DE EN FR IT NL PR SP FishBase [6472]

Froese R., Pauly D. (eds.): FishBase []
CZ AQUATAB. World Wide Web electronic publication [species/8505]

Plíštil J. (Ed.) (2009): AQUATAB. World Wide Web electronic publication [] [as Epinephelus ongus (Bloch, 1790)]
Data retrieved on: 17 January 2010
CZ Hanel L., Plíštil J., Novák J. (2011): České názvy živočichů V. Ryby a rybovití obratlovci (Pisces). 7. Paprskoploutví (Actinopterygii) Kostnatí (Neopterygii) [Ropušnicotvaří (Scorpaeniformes) – ostnoploutví (Perciformes) – Percoidei], Národní muzeum (zoologické oddělení), Praha, 148 str. [as Epinephelus ongus (Bloch, 1790)]
Data retrieved on: 19 August 2019

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