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💧 Freshwater Least Concern 🌡️ Tropical

Nijssen's Hypopygus

Hypopygus nijsseni de Santana & Crampton, 2011
Max Length
9.6 cm
Max Weight
-
Lifespan
-
Trophic Level
3.1
Depth
-
Climate
Tropical
Resilience
-
Vulnerability
10.00/100
Typical Length
-
Depth Zone
-

📖 Overview

Nijssen's Hypopygus (Hypopygus nijsseni), first described by de Santana & Crampton, 2011 is a small fish in the family Rhamphichthyidae (order Gymnotiformes). Adults typically reach 9.60 cm in maximum length. It inhabits freshwater systems including rivers, streams, and lakes. It occurs in Tropical waters. It is broadly omnivorous, taking invertebrates, plant matter, and detritus. On the IUCN Red List, it is classified as Least Concern.

Scientific Name
Hypopygus nijsseni
Authority
de Santana & Crampton, 2011
Habitat
Freshwater
Climate
Tropical
Body Shape
Elongated
IUCN Status
LC
Max Length
9.6 cm
Trophic Level
3.1
Vulnerability
10.00/100
Salinity
0–0.5 ppt

🐟 Physical Description

Hypopygus nijsseni is diagnosed from congeners by the following combination of characters: the total number of anal-fin rays (145–152 versus 102–135 in H. hoedemani, H. lepturus, and H. minissimus; 155–174 in H. cryptogenes), the presence of the sixth infraorbital bone (versus absence in H. hoedemani, H. lepturus, and H. minissimus), the presence of oblique bands (versus absence in H. minissimus), the presence of scales at midbody (versus absence in H. minissimus), the dorsal rami of intermittent branch of anterior lateral line nerve visible as two black parallel lines (versus not visible in H. ortegai), the head length (13.2–15.3% of LEA versus 12.6–13.9 in H. ortegai), the distance at the nape (12.5–13.8% of LEA versus 11.0–12.5 in H. ortegai), the total number of pectoral fin rays (ten to 12 versus 12–16 in H. isbruckeri), the number of scales above the lateral line (five to six versus seven to eight in H. isbruckeri), and the distance from the anus to the anal fin (7.9–9.4% of LEA versus 10.0–12.0 in H. neblinae) .: elongated; Cross section: other (see Diagnosi.

🌀 Behaviour

Behavioural data for Nijssen's Hypopygus 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: Hypopygus nijsseni is known only from small streams in the vicinity of Tefé (Ref.

🌿 Ecology

Zone Preferences
💧 Freshwater
Trophic Level
3.1±0.4

📐 Morphometrics

Length–Weight Relationship: W = 0.00269 × L3.07 (TL)
Max TL
9.6cm

🌡️ Water Parameters & Tolerance

Salinity Range
0–0.5ppt

🛡️ Conservation Assessment

IUCN Category
Least Concern
Assessment Date
2018

📊 Population Risk & Fisheries

Fishing Vulnerability
10.00/100
Low vulnerability
Trophic Level
3.1
Predator
Body Shape
Elongated
Climate Zone
Tropical
Described By
de Santana & Crampton, 2011

👥 Community & Contribute

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