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🌊 Marine Least Concern 🌡️ Subtropical

Halfmoon grouper

Epinephelus rivulatus Valenciennes, 1830
Max Length
45 cm
Max Weight
1.4 kg
Lifespan
-
Trophic Level
3.6
Depth
1–150 m
Climate
Subtropical
Resilience
High
Vulnerability
32.00/100
Typical Length
-
Depth Zone
reef

📖 Overview

Sedentary reef-associated species . Occurs on coral reefs, areas with rocky substrata, algal flats and seagrass beds. Feeds on fishes and crustaceans . A protogynous hermaphrodite . Forms spawning aggregations . Solitary (Ref 90102).

Scientific Name
Epinephelus rivulatus
Authority
Valenciennes, 1830
Habitat
Marine
Climate
Subtropical
Body Shape
Fusiform / normal
IUCN Status
LC
Max Length
45 cm
Max Weight
1.4 kg
Depth Range
1–150 m
Latitude
36°S – 36°N
Trophic Level
3.6
Resilience
High
Vulnerability
32.00/100
Salinity
30–40 ppt

🐟 Physical Description

Dorsal spines (total): 11; Dorsal soft rays (total): 16 - 18; Anal spines: 3; Anal soft rays: 8. Characterized by red-brown head; body mottled pale-brown color; 5-6 irregular dark brown bars on body; caudal fin dark brown with pale speckling; body scales ctenoid except cycloid anterodorsally above lateral line, on nape, thorax and abdomen; body with auxiliary scales only anterodorsally behind zone of small cycloid scales; greatest depth of body; 2.7-3.2 in SL; rounded caudal fin; pelvic fins, 1.9-2.4 in head length ; body depth contained 2.7-3.2 times in SL; head length 2.3-2.6 times in SL; head length 2.3-2.6 times in SL; flat to slightly convex interorbital area, dorsal head profile convex; snout length 4.0-5.0 in HL; angular preopercle, with enlarged serrae at angle; straight upper edge of operculum, almost horizontal; posterior and anterior nostril subequal in size; maxilla reaches to or past vertical at rear edge of eye, ventral edge with slight step at distal expansion; 2-3 rows of teeth on midlateral part of lower jaw; pyloric caeca .: fusiform / normal; Cross section: compressed.

🌀 Behaviour

Behavioural data for Halfmoon grouper is currently being reviewed.

🦐 Diet

Diet information for Halfmoon grouper is currently being compiled.

🥚 Reproduction

Size at Maturity
19.4cm TL

A monandric species . Length at sex change = 7.56 cm TL .

🌍 Habitat & Distribution

Marine; reef-associated; depth range 1 - 150 m . Subtropical; 36°N - 36°S, 23°E - 175°E West Pacific: East Africa to the western Pacific, southward into temperate waters of South Africa, Australia, and New Zealand.

🌿 Ecology

Zone Preferences
🌊 Marine 🪸 Reef Associated
Trophic Level
3.6±0.54
🧍 Solitary
Food Items

fishes and crustaceans (Ref

📐 Morphometrics

Length–Weight Relationship: W = 0.0123 × L3.03 (TL)
Max TL
45cm
Max Weight
1,400g
Dorsal Spines
11
Dorsal Rays
17
Anal Spines
3
Anal Rays
8

🌡️ Water Parameters & Tolerance

Salinity Range
30–40ppt

🛡️ Conservation Assessment

IUCN Category
Least Concern
Assessment Date
2017

📊 Population Risk & Fisheries

Population Resilience
High
Minimum doubling time
Fishing Vulnerability
32.00/100
Low vulnerability
Trophic Level
3.6
Predator
Body Shape
Fusiform / normal
Climate Zone
Subtropical
Latitude Range
36°N – 36°S
Described By
Valenciennes, 1830

🌐 Names & Taxonomy

Language Common Names
🇬🇧English Charlie Court Cod · Chinaman rockcod · Dotted Groper · Green-finned Rock-cod · Halfmoon grouper · Halfmoon Rockcod · Red Cod · Rockcod · White-dotted Cod · white-dotted grouper
🌍AFR Koningklip
🌍CES kanic půlměsícový
🇫🇷French Cabot Sale · Cabot sale, Rouge sale · Loche brique · Merou Demi-lune · Rouge Sale
🇯🇵Japanese Shimofurihata · シモフリハタ
🇵🇹Portuguese garoupa-meia-lunada
🇪🇸Spanish Mero Media Luna
🇨🇳Chinese 半月石斑魚 · 石斑 · 霜點石斑魚 · 鱠仔

Scientific Synonyms

Scientific Name Author Year Status
Epinephelus grammatophoros Boulenger 1903 Synonym
Epinephelus grammatophorus Boulenger 1903 Synonym
Epinephelus homosinensis Whitley 1944 Synonym
Epinephelus matterni Fowler 1918 Synonym
Epinephelus raymondi Ogilby 1908 Synonym
Epinephelus rhyncholepis Bleeker 1853 Synonym
Epinephelus rhyncolepis Bleeker 1853 Synonym
Epinephelus spiramen Whitley 1945 Synonym
Serranus rhyncholepis Bleeker 1853 Synonym
Serranus rhyncolepis Bleeker 1853 Synonym
Serranus rivulatus Valenciennes 1830 Synonym
Serranus viridipinnis De Vis 1884 Synonym

🗺️ Global Occurrence Map

Occurrence records from the Global Biodiversity Information Facility (GBIF) - 25 records indexed .

Occurrence density from GBIF View GBIF records ↗

👥 Community & Contribute

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