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💧 Freshwater Near Threatened 🐠 Aquarium 🌡️ Tropical

Least rasbora

Boraras urophthalmoides Kottelat, 1991
Max Length
4 cm
Max Weight
-
Lifespan
-
Trophic Level
3.4
Depth
-
Climate
Tropical
Resilience
High
Vulnerability
10.00/100
Typical Length
-
Depth Zone
-

📖 Overview

Lives in peats and bog wetlands . Occurs in marshes, swamps and ponds with dense growth of fine-leaved aquatic macrophytes. Does not seem to require large open areas. Probably browses on zooplankton in the vegetation. Never seen in markets, but known from the aquarium trade . Uncommonly seen in aquarium trades but widely used as aquarium bait in Ho Chi Minh City, Vietnam .

Scientific Name
Boraras urophthalmoides
Authority
Kottelat, 1991
Habitat
Freshwater
Climate
Tropical
Body Shape
Elongated
IUCN Status
NT
Max Length
4 cm
Trophic Level
3.4
Resilience
High
Vulnerability
10.00/100
Salinity
0–0.5 ppt

🐟 Physical Description

First dorsal-fin ray darkened; dark spot at caudal-fin base and anal-fin base; prominent lateral stripe that fades on peduncle .: elongated.

🌀 Behaviour

Behavioural data for Least rasbora 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

🌿 Ecology

Zone Preferences
💧 Freshwater
Trophic Level
3.4±0.45

📐 Morphometrics

Length–Weight Relationship: W = 0.00575 × L3.09 (TL)
Max TL
4cm

🌡️ Water Parameters & Tolerance

Salinity Range
0–0.5ppt

🛡️ Conservation Assessment

IUCN Category
Near Threatened
Assessment Date
2011

📊 Population Risk & Fisheries

Population Resilience
High
Minimum doubling time
Fishing Vulnerability
10.00/100
Low vulnerability
Trophic Level
3.4
Predator
Body Shape
Elongated
Climate Zone
Tropical
Described By
Kottelat, 1991

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