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🌊 Marine Least Concern 🍽️ Edible 🌡️ Tropical

Thumbprint emperor

Lethrinus harak Fabricius, 1775
Max Length
54.9 cm
Max Weight
2.9 kg
Lifespan
15 yrs
Trophic Level
3.6
Depth
0–20 m
Climate
Tropical
Resilience
Medium
Vulnerability
31.00/100
Typical Length
30 cm
Depth Zone
reef

📖 Overview

Found solitary or in small schools over shallow sandy, coral rubble, mangroves, lagoons, channel and seagrass areas inshore and adjacent to coral reefs. Feeds on polychaetes, crustaceans, mollusks, echinoderms and small fish. Reported to spawn throughout the year during the first five days of the lunar month in large aggregations in Palau. Caught mostly by shore seine, gill nets, traps, and handline. Marketed mostly fresh ; flesh spoils rapidly .

Scientific Name
Lethrinus harak
Authority
Fabricius, 1775
Habitat
Marine
Climate
Tropical
Body Shape
Fusiform / normal
IUCN Status
LC
Max Length
54.9 cm
Max Weight
2.9 kg
Lifespan
15 years
Depth Range
0–20 m
Latitude
32°S – 32°N
Trophic Level
3.6
Resilience
Medium
Vulnerability
31.00/100
Migration
Non-migratory
Salinity
30–40 ppt

🐟 Physical Description

Dorsal spines (total): 10; Dorsal soft rays (total): 9; Anal spines: 3; Anal soft rays: 8. This species is distinguished by the following characters: body moderately deep, its depth 2.6-2.8 times in standard length; head length 0.9-1 times in body depth, 2.7-3.1 times in SL length, dorsal profile near eye distinctly or slightly convex; snout short and blunt, its length about 2.0-2.6 times in HL, measured without the lip the snout is 0.9-1 times in cheek height, its dorsal profile nearly straight, snout angle relative to upper jaw between 60° and 70°; interorbital space convex or almost flat; posterior nostril a narrow longitudinal slit, closer to orbit than anterior nostril; eye situated close to dorsal profile, its length 3.4-4.2 times in HL; cheek not very high, its height 2.3-3.1 times in HL; lateral teeth in jaws of adults molars or rounded; outer surface of maxilla smooth or with a longitudinal ridge; D X,9 the 4th or 5th dorsal-fin spine the longest, its length 2.5-3.1 times in body depth; A III,8 with the first soft ray usually the longest, its length almost equal to or longer or shorter than length of base of soft-rayed portion of anal fin and 1.2-1.6 times in length of entire anal-fin base; pectoral-fin rays 13; pelvic-fin membranes between rays closest to body without dense melanophores; cheek without scales; 46-47 lateral-line scales usually; usually 5 ½ (sometimes 4 ½) scale rows between lateral line and base of middle dorsal-fin spines; 14-16 scale rows in transverse series between origin of anal fin and lateral line; 13-14 rows in lower series of scales around caudal peduncle; 4-8 scales in supratemporal patch; inner surface of pectoral-fin base densely covered with scales; posterior angle of operculum fully scaly. Colour of body olive or grey above, shading to silvery white below; a large elliptical black spot, often broadly edged in yellow, on side directly below lateral line and centered at a vertical near the posterior tip of pectoral fins; sometimes light blue dots bordering lower rim of eye and around nostrils; pectoral, pelvic, dorsal, and anal fins white to pinkish; caudal fin orange or reddish; vertical fins sometimes lightly mottled or striped .: fusiform / normal; Cross section: oval.

🌀 Behaviour

Behavioural data for Thumbprint emperor is currently being reviewed.

🦐 Diet

Diet information for Thumbprint emperor is currently being compiled.

🥚 Reproduction

Size at Maturity
19.5cm TL

🌍 Habitat & Distribution

Marine; brackish; reef-associated; non-migratory; depth range 0 - 20 m . Tropical; 32°N - 32°S, 31°E - 155°W West Pacific: Red Sea and E ast Africa to Samoa, north to southern Japan, south to northeastern Australia.

🌿 Ecology

Zone Preferences
🌊 Marine 🌿 Brackish 🪸 Reef Associated
Migration
Non-migratory
Trophic Level
3.6±0.5
🐠 Schooling 🧍 Solitary
Food Items

polychaetes, crustaceans, mollusks, echinoderms and small fish

📐 Morphometrics

Length–Weight Relationship: W = 0.01445 × L2.98 (TL)
Max TL
54.9cm
Max Weight
2,900g
Dorsal Spines
10
Dorsal Rays
9
Anal Spines
3
Anal Rays
8

🌡️ Water Parameters & Tolerance

Salinity Range
30–40ppt

🛡️ Conservation Assessment

IUCN Category
Least Concern
Assessment Date
2015

📊 Population Risk & Fisheries

Population Resilience
Medium
Minimum doubling time
Fishing Vulnerability
31.00/100
Low vulnerability
Trophic Level
3.6
Predator
Body Shape
Fusiform / normal
Climate Zone
Tropical
Latitude Range
32°N – 32°S
Described By
Fabricius, 1775

🍽️ Edibility & Flavour

"Thumbprint emperor is an edible species."

✗ Not for Raw
✓ Fresh Indicators
  • Clear, bright eyes — cloudy eyes indicate age
  • Firm flesh that springs back when pressed
  • Fresh ocean smell, never strong or ammonia-like
  • Bright red or pink gills, not grey or brown
  • Shiny, moist skin with scales tightly attached
✗ Avoid If
  • Cloudy or sunken eyes
  • Strong fishy or ammonia odour
  • Soft, mushy flesh that doesn't spring back
  • Discoloured or dry flesh
Best Cooking Methods
Baking Grilling Pan-frying

Nutrition

Per 100g cooked - Source: USDA FoodData Central

Nutrient Amount
Protein 20.5 g
Omega-3 (total) 128 mg

🔬 Mercury Safety

Mercury data for Thumbprint emperor has not yet been assigned. Please consult FDA/EPA guidance for general seafood safety advice.

🌿 Sustainability

Best Choice
Healthy stocks, low impact
Good Alternative
Well-managed, minor concerns
Use Caution
Check sourcing and season
Avoid
Overfished or high impact

🌐 Names & Taxonomy

Language Common Names
🇬🇧English Black Blotch Emperor · Black-blotch Emperor · Blackspot emperor · Thumbprint Emperor
🌍CES cejnovka černoskvrnná
🇩🇪German Schwarzfleck-Straßenkehrer
🇫🇷French Bossu d'herbe · Bossu taché · Capitaine saint-pierre · Empereur Saint Pierre · Empereur Saint Pierre, Capitaine saint-pierre · Empereur Saint-Pierre
🌍HEB שורי הכתם
🇮🇹Italian Pesce imperatore macchia nera
🇯🇵Japanese Matofuefuki · マトフエフキ
🌍MSA Pelandok
🇳🇱Dutch Zwartvlekstraatveger
🇵🇹Portuguese Imperador-manchado
🇷🇺Russian Краснопёрый летрин
🇪🇸Spanish Emperador San Pedro
🇨🇳Chinese 單斑龍占 · 單斑龍占魚 · 黑點裸頰鯛 · 龍占 · 龍尖

Scientific Synonyms

Scientific Name Author Year Status
Lethrinus azureus Valenciennes 1830 Synonym
Lethrinus bleekeri Klunzinger 1884 Synonym
Lethrinus bonhamensis Günther 1874 Synonym
Lethrinus johnii Castelnau 1873 Synonym
Lethrinus papuensis Alleyne & Macleay 1877 Synonym
Lethrinus rhodopterus Bleeker 1852 Synonym
Sciaena harak Forsskål 1775 Synonym

🗺️ Global Occurrence Map

Occurrence records from the Global Biodiversity Information Facility (GBIF) - 20 records indexed .

Occurrence density from GBIF View GBIF records ↗

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