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🌊 Marine 🍽️ Edible 🎣 Game Fish 🌡️ Tropical

Blackspot threadfin

Polydactylus sextarius Bloch & Schneider, 1801
Max Length
30 cm
Max Weight
-
Lifespan
-
Trophic Level
3.8
Depth
16–73 m
Climate
Tropical
Resilience
Medium
Vulnerability
31.00/100
Typical Length
20 cm
Depth Zone
demersal

📖 Overview

A marine species found on sandy and muddy bottoms of the continental shelf . Frequently enters estuaries . Feeds mainly on small crustaceans (especially shrimps), fishes and benthic organisms; also on sponges and fish scales . The progression in this hermaphrodite is protandrous, changing from a juvenile to a hermaphrodite, then a female .

Scientific Name
Polydactylus sextarius
Authority
Bloch & Schneider, 1801
Habitat
Marine
Climate
Tropical
Body Shape
Short and / or deep
Max Length
30 cm
Depth Range
16–73 m
Latitude
11°S – 37°N
Trophic Level
3.8
Resilience
Medium
Vulnerability
31.00/100
Migration
Amphidromous
Salinity
30–40 ppt

🔬 Taxonomy

🐟 Physical Description

Dorsal spines (total): 9; Dorsal soft rays (total): 12 - 13; Anal spines: 3; Anal soft rays: 11 - 13; Vertebrae: 24. With 6 pectoral filaments; uppermost not reaching posterior tip of pectoral fin. Pectoral fin, rays moderate, 19-25% of SL; all rays branched except uppermost 1 or 2. Second dorsal spine short, 5-8% of SL. Atrophied swim bladder, like a string. A large black spot anteriorly on lateral line . No upper lip; lower lip well-developed except at symphysis. Operculum broadly rounded; preoperculum coarsely serrated. Color is golden-olive above ,silvery below. A large oval blotch is at the start of the lateral line .: short and / or deep; Cross section: compressed.

🌀 Behaviour

Behavioural data for Blackspot threadfin is currently being reviewed.

🦐 Diet

Diet information for Blackspot threadfin is currently being compiled.

🥚 Reproduction

Reproduction data for Blackspot threadfin is currently being compiled.

🌍 Habitat & Distribution

Marine; brackish; demersal; amphidromous ; depth range 16 - 73 m . Tropical; 37°N - 11°S, 75°E - 149°E north to Japan.

🌿 Ecology

Zone Preferences
🌊 Marine 🌿 Brackish ⬇️ Benthic
Migration
Amphidromous
Trophic Level
3.8±0.57
Food Items

small crustaceans (especially shrimps), fishes and benthic organisms; also on sponges and fish scale

📐 Morphometrics

Length–Weight Relationship: W = 0.01479 × L3.04 (TL)
Max TL
30cm
Dorsal Spines
9
Dorsal Rays
13
Anal Spines
3
Anal Rays
12
Vertebrae
24

🌡️ Water Parameters & Tolerance

Salinity Range
30–40ppt

📊 Population Risk & Fisheries

Population Resilience
Medium
Minimum doubling time
Fishing Vulnerability
31.00/100
Low vulnerability
Trophic Level
3.8
Predator
Body Shape
Short and / or deep
Climate Zone
Tropical
Latitude Range
37°N – 11°S
Described By
Bloch & Schneider, 1801

🍽️ Edibility & Flavour

"Blackspot threadfin 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

Detailed nutritional data for Blackspot threadfin is currently being compiled from USDA FoodData Central.

🔬 Mercury Safety

Mercury data for Blackspot threadfin 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 blackspot threadfin · sixfinger threadfish
🇸🇦Arabic خيطي الزعانف أسود النقطة
🌍CES smuhovec černoskrvrnný
🇩🇰Danish Sortplettet trådfinnefisk
🇫🇷French barbure à tâche noire
🇯🇵Japanese Kataguroagonashi · kataguro-agonashi · カタグロアゴナシ
🌍MYA za yaw
🇵🇹Portuguese Barbudo-de-mancha-preta
🇷🇺Russian Пятнистый пальцепёр
🌍SIN kutlikala
🇪🇸Spanish barbudo de mancha negra
🌍THA ปลากุเลากาบกล้วย
🇨🇳Chinese 六指多指馬鮁 · 六指馬鮁 · 午仔 · 黑斑多指馬鮁

Scientific Synonyms

Scientific Name Author Year Status
Polynemus sextarius Bloch & Schneider 1801 Synonym
Trichidion sextarius Bloch & Schneider 1801 Synonym

🗺️ Global Occurrence Map

Occurrence records from the Global Biodiversity Information Facility (GBIF) - 11 records indexed .

Occurrence density from GBIF View GBIF records ↗

👥 Community & Contribute

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