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💧 Freshwater Least Concern 🌡️ Tropical

Betta Falx

Betta falx Tan & Kottelat, 1998
Max Length
3.5 cm
Max Weight
Lifespan
Trophic Level
3.1
Depth
Climate
Tropical
Resilience
High
Vulnerability
10.00/100
Typical Length
Depth Zone

📖 Overview

Facultative air-breathing ; Typically found among submerged bank vegetation, in near stagnant waters, with pH 4.7-6.8. Latin word falx means scythe, alluding to the continuous curved shape of the broad anal and caudal distal margins of a male in display. Caudal fin rounded.

Scientific Name
Betta falx
Authority
Tan & Kottelat, 1998
Habitat
Freshwater
Climate
Tropical
Body Shape
Fusiform / normal
IUCN Status
LC
Max Length
3.5 cm
Trophic Level
3.1
Resilience
High
Vulnerability
10.00/100
Salinity
0–0.5 ppt

🐟 Physical Description

Dorsal spines (total): 1 - 2; Dorsal soft rays (total): 7 - 8; Anal spines: 2; Anal soft rays: 19 - 21. This species is closely related to Betta picta from Java where it can be distinguished in the following characters: fewer dorsal fin rays (mode 8 vs. 9); fewer lateral scales (mode 27 vs. 28); dorsal fin origin above 11-12th lateral scale (vs. 12-14th); anal fin origin below modal 6th lateral scale (vs. 7th); fewer predorsal scales (mode 19 vs. 20); slightly greater anal-fin base length (46.5-50.3% SL vs. 42.6-48.4); anal and caudal fins with reddish distal band in live male (vs. bluish); iridescent greenish-blue opercle scales (vs. yellow-gold); in preserved specimens, male with distinct dorsal transverse bars (vs. faint); male with distinct dark anal distal margin wide (vs. narrow); male without elongated median caudal fin rays (vs. presence); female with distinct caudal transverse bars (vs. very faint or absent); dorsal head view narrow (vs. broad); thick preorbital black stripe (vs. narrow); and the distance between posterior part of anal fin to lower part of caudal narrow (vs. wide) .: fusiform / normal.

🌀 Behaviour

Behavioural data for Betta Falx is currently being reviewed.

🦐 Diet

Diet information for Betta Falx is currently being compiled.

🥚 Reproduction

Reproduction data for Betta Falx is currently being compiled.

🌍 Habitat & Distribution

Freshwater; benthopelagic. Tropical central Sumatra, Indonesia.

🌿 Ecology

Zone Preferences
💧 Freshwater
Trophic Level
3.1±0.4

📐 Morphometrics

Length–Weight Relationship: W = 0.00977 × L2.97 (TL)
Max TL
3.5cm
Dorsal Spines
2
Dorsal Rays
8
Anal Spines
2
Anal Rays
20

🌡️ Water Parameters & Tolerance

Salinity Range
0–0.5ppt

🛡️ Conservation Assessment

IUCN Category
Least Concern
Assessment Date
2019

📊 Population Risk & Fisheries

Population Resilience
High
Minimum doubling time
Fishing Vulnerability
10.00/100
Low vulnerability
Trophic Level
3.1
Predator
Body Shape
Fusiform / normal
Climate Zone
Tropical
Described By
Tan & Kottelat, 1998

🗺️ 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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