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💧 Freshwater Endangered 🌡️ Tropical

Fly River rainbowfish

Melanotaenia sexlineata Munro, 1964
Max Length
7.3 cm
Max Weight
-
Lifespan
-
Trophic Level
2.9
Depth
-
Climate
Tropical
Resilience
Medium
Vulnerability
32.00/100
Typical Length
-
Depth Zone
-

📖 Overview

Generally found in small rainforest creeks. An omnivorous egg layer and a peaceful community fish which prefers the following aquarium conditions: pH=7.1, H=8, 27°C water temperature, vegetative cover .

Scientific Name
Melanotaenia sexlineata
Authority
Munro, 1964
Habitat
Freshwater
Climate
Tropical
Body Shape
Fusiform / normal
IUCN Status
EN
Max Length
7.3 cm
Trophic Level
2.9
Resilience
Medium
Vulnerability
32.00/100
Water Temp
24–26 °C
Salinity
0–0.5 ppt

🐟 Physical Description

Dorsal spines (total): 6 - 8; Dorsal soft rays (total): 10 - 12; Anal spines: 1; Anal soft rays: 16 - 19. : fusiform / normal.

🌀 Behaviour

Behavioural data for Fly River rainbowfish is currently being reviewed.

🦐 Diet

aquatic invertebrates
small fish
algae
detritus

🥚 Reproduction

🐣 Oviparous
Spawning Season
spring
Spawn Location
Substrate
Fertilization
External

Distinct pairing .

🌍 Habitat & Distribution

Freshwater; benthopelagic; pH range: 7.0 - 7.5. Tropical; 24°C - 26°C ; 6°S - 8°S known only from a few sites in the upper Fly River system near Kiunga, Papua New Guinea.

🌿 Ecology

Zone Preferences
💧 Freshwater
Trophic Level
2.9±0.4

📐 Morphometrics

Length–Weight Relationship: W = 0.01122 × L3.04 (TL)
Max TL
7.3cm
Dorsal Spines
7
Dorsal Rays
11
Anal Spines
1
Anal Rays
18

🌡️ Water Parameters & Tolerance

Temperature Range
24–26°C
pH Range
7–7.5
Salinity Range
0–0.5ppt

🛡️ Conservation Assessment

IUCN Category
Endangered
Assessment Date
2019

📊 Population Risk & Fisheries

Population Resilience
Medium
Minimum doubling time
Fishing Vulnerability
32.00/100
Low vulnerability
Trophic Level
2.9
Omnivore / Planktivore
Body Shape
Fusiform / normal
Climate Zone
Tropical
Described By
Munro, 1964

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