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🌊 Marine Data Deficient 🌡️ Tropical

Longfin dottyback

Manonichthys polynemus Fowler, 1931
Max Length
12 cm
Max Weight
-
Lifespan
-
Trophic Level
3.7
Depth
2–50 m
Climate
Tropical
Resilience
High
Vulnerability
22.00/100
Typical Length
-
Depth Zone
reef

📖 Overview

An uncommon species that inhabits steep outer reef slopes, in areas with dense coral growth . Solitary, sometimes seen entering sponges (Ref 90102).

Scientific Name
Manonichthys polynemus
Authority
Fowler, 1931
Habitat
Marine
Climate
Tropical
Body Shape
Elongated
IUCN Status
DD
Max Length
12 cm
Depth Range
2–50 m
Latitude
9°S – 19°N
Trophic Level
3.7
Resilience
High
Vulnerability
22.00/100
Salinity
30–40 ppt

🔬 Taxonomy

Genus
Manonichthys
Manonichthys
Species
Longfin dottyback
Manonichthys polynemus

🐟 Physical Description

Dorsal spines (total): 3; Dorsal soft rays (total): 27 - 29; Anal spines: 3; Anal soft rays: 14 - 15. Recognized by the long ventral fins, filamentous median fins, and yellow tear-mark below the eye. Found on steep slopes and walls with tubular sponges, usually in depths of about 20 m . : elongated; Cross section: compressed.

🌀 Behaviour

Behavioural data for Longfin dottyback is currently being reviewed.

🦐 Diet

aquatic invertebrates
small fish
algae
detritus

🥚 Reproduction

🐣 Oviparous 📦 Batch Spawner
Spawning Season
spring-summer
Spawn Location
Pelagic
Fertilization
External

🌍 Habitat & Distribution

Marine; reef-associated; depth range 2 - 50 m . Tropical; 19°N - 9°S

🌿 Ecology

Zone Preferences
🌊 Marine 🪸 Reef Associated
Trophic Level
3.7±0.5
🧍 Solitary

📐 Morphometrics

Length–Weight Relationship: W = 0.0049 × L3.11 (TL)
Max TL
12cm
Dorsal Spines
3
Dorsal Rays
28
Anal Spines
3
Anal Rays
15

🌡️ Water Parameters & Tolerance

Salinity Range
30–40ppt

🛡️ Conservation Assessment

IUCN Category
Data Deficient
Assessment Date
2015

📊 Population Risk & Fisheries

Population Resilience
High
Minimum doubling time
Fishing Vulnerability
22.00/100
Low vulnerability
Trophic Level
3.7
Predator
Body Shape
Elongated
Climate Zone
Tropical
Latitude Range
19°N – 9°S
Described By
Fowler, 1931

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