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💧 Freshwater Critically Endangered 🌡️ Subtropical

Naked characin

Gymnocharacinus bergii Steindachner, 1903
Max Length
7.5 cm
Max Weight
-
Lifespan
-
Trophic Level
3.1
Depth
-
Climate
Subtropical
Resilience
High
Vulnerability
22.00/100
Typical Length
-
Depth Zone
demersal

📖 Overview

Medium sized fish considered to be the most southern characid living in temperate waters. Young with very tiny soft and delicate scales which are reabsorbed into the skin making the skin greasy and often with granulated or spongy appearance .

Scientific Name
Gymnocharacinus bergii
Authority
Steindachner, 1903
Habitat
Freshwater
Climate
Subtropical
Body Shape
Elongated
IUCN Status
CR
Max Length
7.5 cm
Trophic Level
3.1
Resilience
High
Vulnerability
22.00/100
Water Temp
22–26 °C
Salinity
0–0.5 ppt

🔬 Taxonomy

Genus
Gymnocharacinus
Gymnocharacinus
Species
Naked characin
Gymnocharacinus bergii

🐟 Physical Description

Dorsal spines (total): 0; Dorsal soft rays (total): 12; Anal spines: 0; Anal soft rays: 19. Entirely naked (scale only shown on lateral line in specimens > 5 cm TL; head profile obtuse. Color is dark brown, greenish, the belly is cream; there is a copper-colored band on the flanks .: elongated.

🌀 Behaviour

Behavioural data for Naked characin is currently being reviewed.

🦐 Diet

aquatic invertebrates
small fish
algae
detritus

🥚 Reproduction

Size at Maturity
3.8cm TL

🌍 Habitat & Distribution

Freshwater; demersal. Subtropical; 22°C - 26°C ; 35°S - 36°S South America: Valcheta stream in Rio Negro basin, Southern Argentina.

🌿 Ecology

Zone Preferences
💧 Freshwater ⬇️ Benthic
Trophic Level
3.1±0.4

📐 Morphometrics

Length–Weight Relationship: W = 0.00389 × L3.12 (TL)
Max TL
7.5cm
Dorsal Rays
12
Anal Rays
19

🌡️ Water Parameters & Tolerance

Temperature Range
22–26°C
Salinity Range
0–0.5ppt

🛡️ Conservation Assessment

IUCN Category
Critically Endangered
Assessment Date
2017

📊 Population Risk & Fisheries

Population Resilience
High
Minimum doubling time
Fishing Vulnerability
22.00/100
Low vulnerability
Trophic Level
3.1
Predator
Body Shape
Elongated
Climate Zone
Subtropical
Described By
Steindachner, 1903

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