Taxon profile


Epinephelus diacanthus (Valenciennes, 1828)

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

Serranus diacanthus Valenciennes, 1828
Epinephelus dayi Bleeker, 1874

Near Threatened NT


Body depth contained 2.8 to 3.5 times in standard length (for fish 10 to 34 cm standard length). Head large, its length contained 2.2 to 2.4 times in standard length; interorbital region flat or slightly convex, the dorsal profile convex; preopercle with 1 to 5 prominent spines at the angle; upper edge of operculum straight or slightly convex: nostrils subequal; anterior nostrils tubular, the margin usually with a large, bilobed flap of skin; maxilla reaches to or almost to vertical at rear edge of eye, the lower edge smoothly curved; midlateral part of lower jaw with 2 rows of short, subequal teeth. Gill rakers 8 to 10 on upper limb, 15 to 17 on lower limb; numerous bony plates on sides of gill arches. Dorsal fin with XI spines and 15 to 17 rays, the third or fourth spine longest, its length contained 2.8 to 3.6 times in head length and longer than longest ray, the interspinous membranes incised; anal fin with III spines and 8 rays; pectoral fins with 17 to 20 rays; pectoral-fin length contained 1.7 to 2.1 times in head length; pelvic fins end well short of anus, their length contained 2.0 to 2.6 times in head length; caudal fin usually rounded or convex: caudal-peduncle depth contained 3.7 to 4.7 times in head length. Lateral-body scales ctenoid, with auxiliary scales in adults; lateral-line scales 52 to 60; lateral-scale series 103 to 121. Pyloric caeca 7 or 8.
Colour: Body pale greyish brown, usually with 5 dark vertical bars broader than interspaces, 4 below dorsal fin and fifth (faintest) on peduncle; ventral part of head and body often pink or reddish; dark maxillary streak continues faintly to lower edge of preopercle; fins dusky grey without spots.


E. diacanthus occurs on the continental shelf of the northern Indian Ocean from the Gulf of Aden to Sri Lanka and Madras, India. Not known from the Persian Gulf or the Red Sea.


E. diacanthus occurs on mud or muddy sand bottom in depths of 10 to 120 m.


According to Boulenger (1895), this species attains 52 cm total length.

Interchangeable taxa

Records of E. diacanthus from the western Pacific are based on misidentifications of E. stictus: Japan (Katayama, 1988), Hong Kong (Chan, 1968), Viet Nam (Fourmanoir, 1965); or E. fasciatomaculos : Burgess et al., 1988), Taiwan (Shen, 1984). Records from South Africa (Fowler, 1925, 1934; Smith, 1949, 1961) are misidentifications of E. rivulatus. E. diacanthus is similar to the allopatric species E. sexfasciatus and E. stictus, which also have 5 dark bars on the body and distinctly enlarged serrae at the angle of the preopercle. E. sexfasciatus, the western Pacific sister species of E. diacanthus, differs in having black spots on the median fins, fewer scales (lateral-line 46 to 51, lateral-scale series 82 to 96), a smaller head (length contained 2.4 to 2.6 times in standard length) and deeper caudal peduncle (depth contained 2.6 to 3.4 times in head length). E. stictus has numerous black dots on the head and front part of the body, fewer scales (lateral-line 48 to 51, lateral-scale series 84 to 96) and no auxiliary scales.


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 [7340]

Froese R., Pauly D. (eds.): FishBase []
CZ AQUATAB. World Wide Web electronic publication [species/8458]

Plíštil J. (Ed.) (2009): AQUATAB. World Wide Web electronic publication [] [as Epinephelus diacanthus (Valenciennes, 1828)]
Data retrieved on: 17 January 2010
EN IUCN Red List of Threatened Species 2018-1 [132777]

IUCN Red List of Threatened Species [] [as Epinephelus diacanthus (Valenciennes, 1828)]
Data retrieved on: 3 August 2018
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 diacanthus (Valenciennes, 1828)]
Data retrieved on: 19 August 2019

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