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💧 Freshwater Data Deficient 🍽️ Edible 🌡️ Tropical

River threadfin

Polydactylus macrophthalmus Bleeker, 1858
Max Length
52 cm
Max Weight
Lifespan
Trophic Level
3.7
Depth
Climate
Tropical
Resilience
High
Vulnerability
29.00/100
Typical Length
Depth Zone
demersal

📖 Overview

Known only from three rivers on two Indonesian islands: Kapuas River, Kalimantan and Musi and Batanghari rivers, Sumatra. These rivers were part of one large river, the ancient Central or North Sunda River, on the Sundaland during the Pleistocene, the last cold period about 12,000 years ago. Geographic evidence indicates that the species was well adapted to the freshwater basins in this extensive Pleistocene river, whereas other Polydactylus species are generally marine. With Sundaland submerged to about 100 m, this species is now restricted to the 3 presently known localities. The longer pectoral filaments and a more slender body have been considered as an adaptation to its freshwater existence. The long pectoral filaments are useful as a sense organ to search for food in muddy waters . A food fish along the Kapuas River, Borneo .

Scientific Name
Polydactylus macrophthalmus
Authority
Bleeker, 1858
Habitat
Freshwater
Climate
Tropical
Body Shape
Short and / or deep
IUCN Status
DD
Max Length
52 cm
Trophic Level
3.7
Resilience
High
Vulnerability
29.00/100
Salinity
0–0.5 ppt

🐟 Physical Description

Dorsal spines (total): 9; Dorsal soft rays (total): 13 - 14; Anal spines: 3; Anal soft rays: 11. Occipital profile concave in adults. Pectoral filaments 7 with 3 filaments extending beyond caudal fin base and the fifth extending beyond tip of caudal fin lobe. Long pectoral fin rays, 24-26% of SL .: short and / or deep; Cross section: compressed.

🌀 Behaviour

Behavioural data for River threadfin is currently being reviewed.

🦐 Diet

Diet information for River threadfin is currently being compiled.

🥚 Reproduction

Reproduction data for River threadfin is currently being compiled.

🌍 Habitat & Distribution

Freshwater; demersal. Tropical

🌿 Ecology

Zone Preferences
💧 Freshwater ⬇️ Benthic
Trophic Level
3.7±0.5

📐 Morphometrics

Length–Weight Relationship: W = 0.01738 × L3.05 (TL)
Max TL
52cm
Dorsal Spines
9
Dorsal Rays
14
Anal Spines
3
Anal Rays
11

🌡️ Water Parameters & Tolerance

Salinity Range
0–0.5ppt

🛡️ Conservation Assessment

IUCN Category
Data Deficient
Assessment Date
2018

📊 Population Risk & Fisheries

Population Resilience
High
Minimum doubling time
Fishing Vulnerability
29.00/100
Low vulnerability
Trophic Level
3.7
Predator
Body Shape
Short and / or deep
Climate Zone
Tropical
Described By
Bleeker, 1858

🍽️ Edibility & Flavour

Nutrition

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

🔬 Mercury Safety

Mercury data for River 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

👥 Community & Contribute

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