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🌊 Marine Data Deficient 🐠 Aquarium 🌡️ Tropical

Gymnapogon Janus

Gymnapogon janus Fraser, 2016
Max Length
6.3 cm
Max Weight
-
Lifespan
-
Trophic Level
3.4
Depth
0–38 m
Climate
Tropical
Resilience
High
Vulnerability
11.00/100
Typical Length
-
Depth Zone
-

📖 Overview

Gymnapogon Janus (Gymnapogon janus), first described by Fraser, 2016 is a small fish in the family Apogonidae (order Apogoniformes). Adults typically reach 6.30 cm in maximum length. It inhabits marine coastal and open-ocean environments. Recorded depth range: 0 to 38 metres. It occurs in Tropical waters. It feeds on a mix of small fish and invertebrates as a mid-level predator. On the IUCN Red List, it is classified as Data Deficient.The species is kept in the aquarium hobby. Care requirements and behaviour align broadly with other Apogonidae kept in the hobby.

Scientific Name
Gymnapogon janus
Authority
Fraser, 2016
Habitat
Marine
Climate
Tropical
IUCN Status
DD
Max Length
6.3 cm
Depth Range
0–38 m
Trophic Level
3.4
Resilience
High
Vulnerability
11.00/100
Salinity
30–40 ppt

🐟 Physical Description

Dorsal spines (total): 7; Dorsal soft rays (total): 10; Anal spines: 2; Anal soft rays: 9 - 10; Vertebrae: 24. This species is distinguished by the following characters: A 9-10 with anterior-most ray unbranched; D 10, the two anterior-most rays unbranched; pectoral fins 14, 9 branched and 5 unbranched; caudal fin rounded, principal caudal rays 17. 15 branched; vomer with one row of two villiform teeth on each side .Cross section: oval.

🌀 Behaviour

Behavioural data for Gymnapogon Janus is currently being reviewed.

🦐 Diet

aquatic invertebrates
small fish
algae
detritus

🥚 Reproduction

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

🌍 Habitat & Distribution

Marine; benthopelagic; depth range 0 - 38 m . Tropical Central Pacific: Philippines.

🌿 Ecology

Zone Preferences
🌊 Marine
Trophic Level
3.4±0.5

📐 Morphometrics

Length–Weight Relationship: W = 0.00389 × L3.12 (TL)
Max TL
6.3cm
Dorsal Spines
7
Dorsal Rays
10
Anal Spines
2
Anal Rays
10
Vertebrae
24

🌡️ Water Parameters & Tolerance

Salinity Range
30–40ppt

🛡️ Conservation Assessment

IUCN Category
Data Deficient
Assessment Date
2023

📊 Population Risk & Fisheries

Population Resilience
High
Minimum doubling time
Fishing Vulnerability
11.00/100
Low vulnerability
Trophic Level
3.4
Predator
Climate Zone
Tropical
Described By
Fraser, 2016

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