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💧 Freshwater Data Deficient 🌡️ Tropical

Trombetas knifefish

Rhamphichthys longior Triques, 1999
Max Length
80 cm
Max Weight
-
Lifespan
-
Trophic Level
3.3
Depth
-
Climate
Tropical
Resilience
-
Vulnerability
51.00/100
Typical Length
-
Depth Zone
-

📖 Overview

Trombetas knifefish (Rhamphichthys longior) is a ray-finned fish of the family Rhamphichthyidae. It inhabits freshwater waters. This species can reach a maximum total length of 80 cm. With a trophic level of 3.3, 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
Rhamphichthys longior
Authority
Triques, 1999
Habitat
Freshwater
Climate
Tropical
Body Shape
Elongated
IUCN Status
DD
Max Length
80 cm
Trophic Level
3.3
Vulnerability
51.00/100
Salinity
0–0.5 ppt

🔬 Taxonomy

🐟 Physical Description

Dorsal spines (total): 0; Dorsal soft rays (total): 0. Body depth 7.3 to 7.6% of the anal fin length. Head length 10.8 to 11.1% of the anal fin length. No caudal fin .: elongated; Cross section: compressed.

🌀 Behaviour

Behavioural data for Trombetas knifefish 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: Paru Lake in the lower Amazon River basin, Brazil.

🌿 Ecology

Zone Preferences
💧 Freshwater
Trophic Level
3.3±0.4

📐 Morphometrics

Length–Weight Relationship: W = 0.00269 × L3.07 (TL)
Max TL
80cm

🌡️ Water Parameters & Tolerance

Salinity Range
0–0.5ppt

🛡️ Conservation Assessment

IUCN Category
Data Deficient
Assessment Date
2020

📊 Population Risk & Fisheries

Fishing Vulnerability
51.00/100
Moderate-High vulnerability
Trophic Level
3.3
Predator
Body Shape
Elongated
Climate Zone
Tropical
Described By
Triques, 1999

🌐 Names & Taxonomy

Language Common Names
🇬🇧English Knifefish · Sand Knife Fish

📚 Scientific References

13 publications cited

General
  1. Froese, R. and Pauly, D. (Editors) (2024). FishBase. World Wide Web electronic publication. FishBase Consortium. Link ↗
Conservation
  1. IUCN (2024). The IUCN Red List of Threatened Species. Version 2024-1. International Union for Conservation of Nature. Link ↗
Taxonomy
  1. GBIF Secretariat (2024). GBIF Backbone Taxonomy. Checklist dataset. Global Biodiversity Information Facility. DOI ↗
Nutrition
  1. USDA Agricultural Research Service (2024). FoodData Central. USDA National Nutrient Database. United States Department of Agriculture. Link ↗
Fishery
  1. NOAA Fisheries (2024). FishWatch: U.S. Seafood Facts. National Oceanic and Atmospheric Administration. Link ↗
  2. Monterey Bay Aquarium (2024). Seafood Watch Recommendations. Monterey Bay Aquarium Foundation. Link ↗
Aquaculture
  1. FAO Fisheries and Aquaculture Department (2024). The State of World Fisheries and Aquaculture. Food and Agriculture Organization of the United Nations. Link ↗
Distribution
  1. Kaschner, K., Kesner-Reyes, K., Garilao, C., Segschneider, J., Rius-Barile, J., Rees, T., Froese, R. (2024). AquaMaps: Predicted range maps for aquatic species. AquaMaps. Link ↗
Ecology
  1. Nelson, J.S., Grande, T.C., Wilson, M.V.H. (2016). Fishes of the World. 5th edition. John Wiley & Sons.
Behavior
  1. Helfman, G.S., Collette, B.B., Facey, D.E., Bowen, B.W. (2009). The Diversity of Fishes: Biology, Evolution, and Ecology. 2nd edition. Wiley-Blackwell.
Morphology
  1. Froese, R. (2006). Cube law, condition factor and weight-length relationships: history, meta-analysis and recommendations. Journal of Applied Ichthyology, 22(4), 241-253. DOI ↗
Toxicology
  1. Halstead, B.W., Auerbach, P.S., Campbell, D. (1988). A Colour Atlas of Dangerous Marine Animals. Wolfe Medical Publications. Wolfe Medical.
Reproduction
  1. Balon, E.K. (1975). Reproductive Guilds of Fishes: A Proposal and Definition. Journal of the Fisheries Research Board of Canada, 32(6), 821-864.

🗺️ Global Occurrence Map

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

Occurrence density from GBIF View GBIF records ↗

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