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💧 Freshwater Least Concern 🌡️ Tropical

Sarapó

Gymnotus obscurus Crampton, Thorsen & Albert, 2005
Max Length
21.5 cm
Max Weight
-
Lifespan
-
Trophic Level
3.3
Depth
-
Climate
Tropical
Resilience
High
Vulnerability
21.00/100
Typical Length
-
Depth Zone
-

📖 Overview

Facultative air-breathing in the genus ; Inhabits root mats of floating meadows in floodplains. In the whitewater floodplain, juveniles are encountered in patches of floating macrophytes along lakes margins and along the edge of canos (drainage channels from lakes to the main river channels) and paranás (channels connected at both ends to the main river channel that transport whitewater through the floodplain). Floating macrophytes form extensive floating meadows. Undertakes aerial respiration by gulping atmospheric air into the hypervascularized posterior chamber of the gas bladder. Feeds primarily on chironomid larvae, small insect nymphs and small crustaceans .

Scientific Name
Gymnotus obscurus
Authority
Crampton, Thorsen & Albert, 2005
Habitat
Freshwater
Climate
Tropical
IUCN Status
LC
Max Length
21.5 cm
Trophic Level
3.3
Resilience
High
Vulnerability
21.00/100
Salinity
0–0.5 ppt

🔬 Taxonomy

🐟 Physical Description

Dorsal spines (total): 0; Dorsal soft rays (total): 0; Anal soft rays: 210 - 250. Distinguished from its congeners endemic to the Amazon and Orinoco Basins and the Guyana Shield in having many pectoral-fin rays 20-22; and a color pattern of oblique and undivided thin pale bands, less than one-quarter width of dark bands, with straight high-contrast margins, which extend to the dorsal midline on the anterior half of the body, and of which many are interrupted at the ventral margin of the hypaxial muscles along the anterior two-thirds of the body. Differs further from congeners endemic to the Amazon-Orinoco basins and the Guyana Shield in having the following unique combination of characters: clear (unpigmented) patch at the caudal end of the anal-fin membrane in specimens 6.0-23.5 TL; and bands never divided to form band pairs .

🌀 Behaviour

Behavioural data for Sarapó is currently being reviewed.

🦐 Diet

aquatic invertebrates
small fish
algae
detritus

🥚 Reproduction

🐣 Oviparous
Spawning Season
spring
Spawn Location
Substrate
Fertilization
External

🌍 Habitat & Distribution

Freshwater; benthopelagic. Tropical South America: varzea floodplain at the conflluence of the Rio Solimoes (Amazon) and the Rio Japura in Mamiraua Reserve near the Tefé, Amazonas, Brazil.

🌿 Ecology

Zone Preferences
💧 Freshwater
Trophic Level
3.3±0.4
Food Items

chironomid larvae, small insect nymphs and small crustaceans (Ref

📐 Morphometrics

Length–Weight Relationship: W = 0.00427 × L2.98 (TL)
Max TL
21.5cm
Anal Rays
230

🌡️ Water Parameters & Tolerance

Salinity Range
0–0.5ppt

🛡️ Conservation Assessment

IUCN Category
Least Concern
Assessment Date
2018

📊 Population Risk & Fisheries

Population Resilience
High
Minimum doubling time
Fishing Vulnerability
21.00/100
Low vulnerability
Trophic Level
3.3
Predator
Climate Zone
Tropical
Described By
Crampton, Thorsen & Albert, 2005

🌐 Names & Taxonomy

Language Common Names
🇵🇹Portuguese Sarapó · Tuvira

🗺️ Global Occurrence Map

Occurrence records from the Global Biodiversity Information Facility (GBIF) - 1 records indexed .

Occurrence density from GBIF View GBIF records ↗

👥 Community & Contribute

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