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🌿 Brackish Least Concern 🌡️ Tropical

Estuary croaker

Sonorolux fluminis Trewavas, 1977
Max Length
8 cm
Max Weight
-
Lifespan
-
Trophic Level
3.3
Depth
-
Climate
Tropical
Resilience
High
Vulnerability
10.00/100
Typical Length
-
Depth Zone
-

📖 Overview

Estuary croaker (Sonorolux fluminis) is a ray-finned fish. It inhabits brackish water waters. This species can reach a maximum total length of 8 cm. With a trophic level of 3.3, it is a low-level carnivore, feeding on invertebrates and small organisms. It is assessed as Least Concern on the IUCN Red List.

Scientific Name
Sonorolux fluminis
Authority
Trewavas, 1977
Habitat
Brackish
Climate
Tropical
IUCN Status
LC
Max Length
8 cm
Trophic Level
3.3
Resilience
High
Vulnerability
10.00/100
Migration
Non-migratory

🔬 Taxonomy

Genus
Sonorolux
Sonorolux
Species
Estuary croaker
Sonorolux fluminis

🐟 Physical Description

Dorsal spines (total): 10 - 11; Dorsal soft rays (total): 28 - 29; Anal spines: 2; Anal soft rays: 7 - 8. Deep rounded body. Upper rostral pores absent, marginal rostral pore median only. First pair of mental pores small, rounded, at front of chin, separated by symphysis. Gill rakers long, slender, about 1.5 times as long as gill filaments at angle of arch, 16 to 27 on lower limb. Second anal spine slender, 33-37 % of head length. Scales on head and anterior part of body cycloid (smooth). Small scales present on soft parts of dorsal and anal fins; many of ventral scales covering patches of yellow, luminous tissue. Swim bladder carrot-shaped, with about 20 pairs of arborescent appendages along its side, each with a well-developed dorsal and ventral limbs; the first pair entering head beyond transverse septum. Sagitta (large earstone0 with a tadpole-shaped impression, the tail of which nearly straight, only slightly curved, ending in a rounded disc.

🌀 Behaviour

Behavioural data for Estuary croaker is currently being reviewed.

🦐 Diet

Diet information for Estuary croaker is currently being compiled.

🥚 Reproduction

Reproduction data for Estuary croaker is currently being compiled.

🌍 Habitat & Distribution

Brackish; benthopelagic; non-migratory. Tropical Central Pacific: Sarawak, Borneo.

🌿 Ecology

Zone Preferences
🌿 Brackish
Migration
Non-migratory
Trophic Level
3.3±0.3

📐 Morphometrics

Length–Weight Relationship: W = 0.00575 × L3.13 (TL)
Max TL
8cm
Dorsal Spines
11
Dorsal Rays
29
Anal Spines
2
Anal Rays
8

🛡️ Conservation Assessment

IUCN Category
Least Concern
Assessment Date
2018

📊 Population Risk & Fisheries

Population Resilience
High
Minimum doubling time
Fishing Vulnerability
10.00/100
Low vulnerability
Trophic Level
3.3
Predator
Climate Zone
Tropical
Described By
Trewavas, 1977

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