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💧 Freshwater Least Concern 🌡️ Subtropical

Glass knifefish

Eigenmannia virescens Valenciennes, 1836
Max Length
44 cm
Max Weight
-
Lifespan
-
Trophic Level
3.1
Depth
-
Climate
Subtropical
Resilience
Medium
Vulnerability
41.00/100
Typical Length
-
Depth Zone
-

📖 Overview

Known to be gregarious, timid and nocturnal . Prefers deep still waters . Found in ponds and creeks with a substrate rich in plant debris . This gymnotiform fish can be found in colder waters of 18°C . Electric organ discharge (EOD) frequency cues have been experimentally shown to play a role in species and sex recognition in this species . Playback of a conspecific male's electric courtship display elicited spawning in ripe females. Diel rhythmic change in EOD may be manifested by the increase in EOD amplitude at night among dominant breeding males as they compete with other conspecifics . A fractional spawner; fecundity reported at 905 eggs . Males reportedly reach 45 cm TL, females to 20 cm TL .

Scientific Name
Eigenmannia virescens
Authority
Valenciennes, 1836
Habitat
Freshwater
Climate
Subtropical
IUCN Status
LC
Max Length
44 cm
Trophic Level
3.1
Resilience
Medium
Vulnerability
41.00/100
Water Temp
20–30 °C
Salinity
0–0.5 ppt

🔬 Taxonomy

🐟 Physical Description

Physical description for Glass knifefish is currently being compiled.

🌀 Behaviour

Behavioural data for Glass knifefish is currently being reviewed.

🦐 Diet

aquatic invertebrates
small fish
algae
detritus

🥚 Reproduction

Size at Maturity
11cm TL
Fecundity
100–200eggs

Lays 100-200 eggs which adhere to leaves of aquatic plants .

🌍 Habitat & Distribution

Freshwater; benthopelagic; pH range: 6.0 - 7.0; dH range: 2 - 15. Subtropical; 20°C - 30°C South America: widely distributed east of the Andes from the Orinoco to the La Plata River basins.

🌿 Ecology

Zone Preferences
💧 Freshwater
Trophic Level
3.1±0.3
🌙 Nocturnal

📐 Morphometrics

Length–Weight Relationship: W = 0.00229 × L2.9 (TL)
Max TL
44cm

🌡️ Water Parameters & Tolerance

Temperature Range
20–30°C
pH Range
6–7
Salinity Range
0–0.5ppt

🛡️ Conservation Assessment

IUCN Category
Least Concern
Assessment Date
2020

📊 Population Risk & Fisheries

Population Resilience
Medium
Minimum doubling time
Fishing Vulnerability
41.00/100
Moderate vulnerability
Trophic Level
3.1
Predator
Climate Zone
Subtropical
Described By
Valenciennes, 1836

🗺️ Global Occurrence Map

Occurrence records from the Global Biodiversity Information Facility (GBIF) - 53 records indexed .

Occurrence density from GBIF View GBIF records ↗

👥 Community & Contribute

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