Taxon profile


Blue-lined Grouper
Cephalopholis polleni (Bleeker, 1868)

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

Scientific synonyms

Epinephelus polleni Bleeker, 1868
Gracila polleni (Bleeker, 1868)
Aethaloperca polleni (Bleeker, 1868)
Gracilia polleni (Bleeker, 1868)
Plectropoma lineatum Bliss, 1883
Gracila okinawae Katayama, 1974
Cephalopholis virgatus Fourmanoir, 1955

Other names

= Harlequin Cod
= Harlequin Grouper
= Harlequin Hind

Least Concern LC



Body depth subequal to head length, depth contained 2.7 to 3.1 times in standard length (for fish 9 to 26 cm standard length). Eye diameter subequal to interorbital width and about twice depth of preorbital; preopercle rounded, finely serrate, the lower edge with 1 to 3 broad serrae; subopercle and interopercle finely serrate: maxilla reaches about to vertical at rear edge of eye. Gill rakers 7 or 8 on upper limb, 14 to 17 on lower limb. Dorsal fin with IX spines (with the fin membrane distinctly indented between them) and 14 to 16 rays; anal fin with III spines and 9 (rarely 8) rays; pectoral-fin rays 17 to 19; pectoral fins subequal to pelvic fins, pectoral-fin length contained 1.5 to 1.9 times in head length; caudal fin truncate to slightly emarginate. Lateral-body scales ctenoid, without auxiliary scales; lateral-line scales 66 to 72; lateral-scale series 112 to 135.
Colour: Adults mostly yellow (greenish or brownish yellow on head and anterodorsally on body in some fish), with 10 to 12 bright blue or violet horizontal stripes on body, the upper 2 or 3 broken into segments and extending posteriorly onto dorsal fin; the stripes running onto peduncle bifurcate and continue onto the caudal fin almost to the rear margin; head with 3 to 6 horizontal blue stripes; dark brown maxillary streak present; pelvic fins yellow with blue stripes. Small juveniles (4 cm standard length) yellowish brown, shading to lavender ventrally and to yellow at base of caudal fin, the yellow continuing as a broad band in each caudal lobe; snout yellow, with a large black spot on each side in front of nostrils. Larger juveniles (10 cm standard length) brownish orange with longitudinal purple stripes on head and body.


C. polleni occurs only at oceanic islands of the Indo-Pacific region, from the western Indian Ocean (Comoro Islands, Reunion, Mauritius, Chagos, Maldives) to the central Pacific (Palau and Line Islands); also reported from the Cocos-Keeling Islands, Christmas Island, Indonesia (small islands), Philippines, Okinawa, Guam, and New Britain. It is not known from the Red Sea, Sri Lanka, Australia, larger islands of Indonesia, or New Guinea.


C. polleni is found on coral reefs in clear water on the edge of steep drop-offs: rarely seen in less than 30 m, it has been taken in depths of 120 m and undoubtedly occurs deeper.


Maximum total length 43 cm.


Smith-Vaniz et al. (1988) have shown that C. polleni, which was previously assigned to the genus Gracila, is not closely related to G. albomarginata, the type species of this monotypic genus. The cranium of C. polleni is more similar to that of C. argus than to G. albomarginata, and it also has more robust dorsal and anal-fin spines than in G. albomarginata. Although Smith-Vaniz et al. (1988) did not find any uniquely derived character that could be used to establish the monophyly of the genus Cephalopholis, Heemstra and Randall (1993) provisionally accept their assignment of C. polleni to this genus, since it shares with the species of Cephalopholis a dorsal-fin spine count of IX, a distinct knob on the ventroposterior corner of the maxilla, and has 3 to 5 trisegmental pterygiophores in the dorsal and anal fins. Furthermore, C. polleni lacks the derived characters that distinguish the other grouper genera.


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 [6452]

Froese R., Pauly D. (eds.): FishBase []
CZ AQUATAB. World Wide Web electronic publication [species/5353]

Plíštil J. (Ed.) (2009): AQUATAB. World Wide Web electronic publication [] [as Cephalopholis polleni (Bleeker, 1868)]
Data retrieved on: 17 January 2010
EN IUCN Red List of Threatened Species 2018-1 [132805]

IUCN Red List of Threatened Species [] [as Cephalopholis polleni (Bleeker, 1868)]
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 Cephalopholis polleni (Bleeker, 1868)]
Data retrieved on: 19 August 2019

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