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🌊 Marine Data Deficient 🌡️ Subtropical

Bighead brotula

Grammonus opisthodon Smith, 1934
← All Species
Max Length
5 cm
Max Weight
-
Lifespan
-
Trophic Level
3.2
Depth
-
Climate
Subtropical
Resilience
Low
Vulnerability
10.00/100
Typical Length
-
Depth Zone
demersal

📖 Overview

Bighead brotula (Grammonus opisthodon) is a ray-finned fish of the family Bythitidae. It inhabits marine (saltwater) waters in benthic environments. This species can reach a maximum total length of 5 cm. With a trophic level of 3.2, it is a low-level carnivore, feeding on invertebrates and small organisms. It is assessed as Data Deficient on the IUCN Red List.

Scientific Name
Grammonus opisthodon
Authority
Smith, 1934
Habitat
Marine
Climate
Subtropical
Body Shape
Fusiform / normal
IUCN Status
DD
Max Length
5 cm
Trophic Level
3.2
Resilience
Low
Vulnerability
10.00/100
Salinity
30–40 ppt

🐟 Physical Description

: fusiform / normal.

🌀 Behaviour

Behavioural data for Bighead brotula 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; demersal; depth range ? - 22 m . Subtropical Southeast Atlantic: South Africa.

🌿 Ecology

Zone Preferences
🌊 Marine ⬇️ Benthic
Trophic Level
3.2±0.5

📐 Morphometrics

Length–Weight Relationship: W = 0.01122 × L3.04 (TL)
Max TL
5cm

🌡️ Water Parameters & Tolerance

Salinity Range
30–40ppt

🛡️ Conservation Assessment

IUCN Category
Data Deficient
Assessment Date
2019

📊 Population Risk & Fisheries

Population Resilience
Low
Minimum doubling time
Fishing Vulnerability
10.00/100
Low vulnerability
Trophic Level
3.2
Predator
Body Shape
Fusiform / normal
Climate Zone
Subtropical
Described By
Smith, 1934

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