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🌊 Marine Least Concern 🌡️ Tropical

Smallmouth threadfin

Polydactylus microstoma Bleeker, 1851
Max Length
25 cm
Max Weight
Lifespan
Trophic Level
3.9
Depth
2–55 m
Climate
Tropical
Resilience
High
Vulnerability
17.00/100
Typical Length
20 cm
Depth Zone
demersal

📖 Overview

Found in turbid coastal waters, estuaries and mangrove creeks, and in mangrove-lined rivers . Euryhaline . Feeds mainly on small crustaceans (especially shrimps), fishes and benthic organisms .

Scientific Name
Polydactylus microstoma
Authority
Bleeker, 1851
Habitat
Marine
Climate
Tropical
Body Shape
Short and / or deep
IUCN Status
LC
Max Length
25 cm
Depth Range
2–55 m
Latitude
23°S – 26°N
Trophic Level
3.9
Resilience
High
Vulnerability
17.00/100
Salinity
30–40 ppt

🐟 Physical Description

Dorsal spines (total): 9; Dorsal soft rays (total): 12 - 14; Anal spines: 3; Anal soft rays: 11 - 12; Vertebrae: 10 - 14. With 5 pectoral filaments; uppermost not reaching to (or extending slightly beyond) posterior tip of pectoral fin. Pectoral fin, rays short, 17-20% of SL; all rays branched except uppermost 1 or 2. Second dorsal spine long, 7-9% of SL. Well-developed swim bladder. A large black spot anteriorly on lateral line . Posterior margin of maxilla reaching to (or slightly short of) level of posterior margin of adipose eyelid. Lower tip of 7th proximal pterygiophore of 1st dorsal fin directed backwards. Lateral line squamation on caudal fin unbranched, extending to upper end of lower caudal fin lobe .: short and / or deep; Cross section: compressed.

🌀 Behaviour

Behavioural data for Smallmouth threadfin is currently being reviewed.

🦐 Diet

Diet information for Smallmouth threadfin is currently being compiled.

🥚 Reproduction

Reproduction data for Smallmouth threadfin is currently being compiled.

🌍 Habitat & Distribution

Marine; brackish; demersal; depth range 2 - 55 m . Tropical; 26°N - 23°S, 77°E - 168°E Indian Ocean and Western Pacific: Tamil Nudu, India to Myanmar and Phuket, Thailand; then from Taiwan to Indonesia and New Caledonia.

🌿 Ecology

Zone Preferences
🌊 Marine 🌿 Brackish ⬇️ Benthic
Trophic Level
3.9
Food Items

small crustaceans (especially shrimps), fishes and benthic organisms (Ref

📐 Morphometrics

Length–Weight Relationship: W = 0.01622 × L3.05 (TL)
Max TL
25cm
Dorsal Spines
9
Dorsal Rays
13
Anal Spines
3
Anal Rays
12
Vertebrae
12

🌡️ Water Parameters & Tolerance

Salinity Range
30–40ppt

🛡️ Conservation Assessment

IUCN Category
Least Concern
Assessment Date
2009

📊 Population Risk & Fisheries

Population Resilience
High
Minimum doubling time
Fishing Vulnerability
17.00/100
Low vulnerability
Trophic Level
3.9
Predator
Body Shape
Short and / or deep
Climate Zone
Tropical
Latitude Range
26°N – 23°S
Described By
Bleeker, 1851

👥 Community & Contribute

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