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Diadromous Least Concern 🍽️ Edible 🎣 Game Fish 🌡️ Tropical

Rock flagtail

Kuhlia rupestris Lacepède, 1802
Max Length
45 cm
Max Weight
2.7 kg
Lifespan
-
Trophic Level
3.2
Depth
0–5 m
Climate
Tropical
Resilience
Medium
Vulnerability
44.00/100
Typical Length
25 cm
Depth Zone
reef

📖 Overview

Primarily a freshwater inhabitant but may penetrate adjacent marine habitats . Adults occur in estuaries and the middle reaches of rivers; usually in relatively fast-flowing, clear streams . Usually in rainforests, as well as in rocky pools below waterfalls . Adults are omnivorous, feeding on small fishes, insects, crustaceans and fruits (figs) that drop into the water. Specific breeding habits are unknown, but adults move downstream into estuaries or to the sea to spawn . Neither anterolateral groove nor venom gland is present . Good food fish .

Scientific Name
Kuhlia rupestris
Authority
Lacepède, 1802
Habitat
Diadromous
Climate
Tropical
Body Shape
Fusiform / normal
IUCN Status
LC
Max Length
45 cm
Max Weight
2.7 kg
Depth Range
0–5 m
Trophic Level
3.2
Resilience
Medium
Vulnerability
44.00/100
Migration
Catadromous
Water Temp
20–26 °C
Salinity
30–40 ppt

🔬 Taxonomy

🐟 Physical Description

Dorsal spines (total): 10; Dorsal soft rays (total): 10 - 12; Anal spines: 3; Anal soft rays: 9 - 11. Diagnosis: Preorbital serrae 10-15 (obsolete in large specimens); body depth 2.6-3.0 in SL; mouth large for genus, maxilla reaching to below posterior half of eye; caudal fin emarginate, lobes somewhat rounded, caudal concavity 5.3-8.7 in head length . Reduced number of lateral line scales; 17-18(19) gillrakers on lower part of first bracnhial arch; body with spots . Coloration: Silvery, the scales dorsally on body with black edges, those on side with a black bar or spot; juveniles with a broad black zone, edged above and below in white, in soft portion of dorsal fin, and each lobe of caudal fin with a large, white-edged black spot; black areas in these fins enlarge with growth until in adults most of these fins black (caudal with upper and lower edges and corners whitish) .: fusiform / normal.

🌀 Behaviour

Behavioural data for Rock flagtail is currently being reviewed.

🦐 Diet

aquatic invertebrates
small fish
algae
detritus

🥚 Reproduction

Size at Maturity
26.5cm TL

Presumably non-guarders (RF).

🌍 Habitat & Distribution

Marine; freshwater; brackish; reef-associated; catadromous ; depth range 0 - 5 m . Tropical; 20°C - 26°C East Africa to Samoa, north to the Ryukyu Islands, south to Queensland, Australia and New Caledonia.

🌿 Ecology

Zone Preferences
🌊 Marine 💧 Freshwater 🌿 Brackish 🪸 Reef Associated
Migration
Catadromous
Trophic Level
3.2±0.45

📐 Morphometrics

Length–Weight Relationship: W = 0.01445 × L3.06 (TL)
Max TL
45cm
Max Weight
2,700g
Dorsal Spines
10
Dorsal Rays
11
Anal Spines
3
Anal Rays
10

🌡️ Water Parameters & Tolerance

Temperature Range
20–26°C
Salinity Range
30–40ppt

🛡️ Conservation Assessment

IUCN Category
Least Concern
Assessment Date
2019

📊 Population Risk & Fisheries

Population Resilience
Medium
Minimum doubling time
Fishing Vulnerability
44.00/100
Moderate vulnerability
Trophic Level
3.2
Predator
Body Shape
Fusiform / normal
Climate Zone
Tropical
Described By
Lacepède, 1802

🎣 Angling Guide

Difficulty
Beginner
Fight Rating
strong pulls with head-shakes
Best Seasons
spring,summer,fall
Best Time
incoming tide, dawn and dusk
Line Weight
15-30
Rod Type
medium-heavy spinning
Hook Size
2/0-5/0
Catch & Release
✓ Recommended
Best Months
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Techniques
bottom fishing popping cork soft plastics live bait
Bait & Lures
live shrimp cut mullet soft plastic paddle-tails popping corks
Recommended Tackle
  • medium-heavy 7ft spinning rod
  • 30-50 lb braid
  • fluorocarbon leader
Where to Find Them
  • grass flats
  • oyster bars
  • marsh drains
  • deeper channel edges
Tips & Tricks
Popping cork technique attracts fish from distance. Fish moving tides.
Catch & Release Tips

Use barbless hooks, minimise air exposure, and revive fish head-first in current before release.

Regulations Summary

⚠️ Slot limits protect breeding-size fish. Verify daily bag limits.

🍽️ Edibility & Flavour

"Rock flagtail 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 19.4 g
Omega-3 (total) 111 mg

🔬 Mercury Safety

Mercury data for Rock flagtail 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
✓ Sustainable Choice

🔬 Full Nutritional Profile

Per 100g - Raw, per 100g - Source: USDA FoodData Central templates (generic fish average)

Proximate Composition
Energy125 kcal
Moisture75 %
Protein20 %
Total Fat4 %
Ash1.3 %
Fatty Acids (g)
Saturated Fat1 g
Monounsaturated Fat1.2 g
Polyunsaturated Fat1.5 g
Omega-3 Total1 g
EPA0.3 g
DHA0.5 g
Omega-6 Total0.3 g
Key Minerals & Vitamins
Calcium20 mg
Iron0.7 mg
Magnesium30 mg
Phosphorus220 mg
Potassium380 mg
Sodium55 mg
Zinc0.5 mg
Selenium32 µg
Vitamin B122 µg

📊 Population Dynamics

Year Region Index Notes
- - -

🌐 Names & Taxonomy

Language Common Names
🇬🇧English Buffalo Bream · Jungle Perch · Mountain Trout · Rock flagtail
🌍CES praporkovec skaliskový
🌍CHA Umatan
🇩🇰Danish Klippeflaghale
🇫🇷French Carpe · Doule de roche · Kuhlie des rochers · Kuhlie des rochers, Poisson plat · Maraudeur · Poisson plat, Doule de roche
🇯🇵Japanese Okuchiyugoi · オオクチユゴイ
🇵🇹Portuguese Kuhila-rupestre
🇷🇺Russian Серебристая кулия
🇪🇸Spanish Dara rocosa
🌍THA ปลาหางธง
🇨🇳Chinese 大口湯鯉

🗺️ Global Occurrence Map

Occurrence records from the Global Biodiversity Information Facility (GBIF) - 38 records indexed .

Occurrence density from GBIF View GBIF records ↗

👥 Community & Contribute

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